FT3

MODEL
Fox Thermal Gas Mass Flow Meter

Instruction Manual
Document #104488
Rev K

831.384.4300 | 399 Reservation Rd, Marina, CA 93933 | foxthermal.com

| 2
 Model FT3
Disclaimer

This publication must be read in its entirety before performing any operation. Failure to
understand and follow these instructions could result in serious personal injury and/or
damage to the equipment. Should this equipment require repair or adjustment beyond
the procedures given herein, contact the factory at:

FOX THERMAL INSTRUMENTS, INC.

399 RESERVATION ROAD
MARINA, CA 93933
TELEPHONE: 831-384-4300
EMAIL: SERVICE@FOXTHERMAL.COM

Download Technical Data Sheets from our website:

www.foxthermal.com

Fox Thermal Instruments, Inc. (Fox Thermal) believes that the information
provided herein is accurate; however, be advised that the information contained
herein is NOT a guarantee for satisfactory results. Specifically, this information is
neither a warranty nor guarantee, expressed or implied, regarding performance,
merchantability, fitness, or any other matter with respect to the products; nor
recommendation for the use of the product/process information in conflict with
any patent. Please note that Fox Thermal reserves the right to change and/or
improve the product design and specification without notice.

Fox Thermal FT3 Manuals:

• Fox Thermal FT3 View™ Manual

All Fox Thermal Manuals and software available in English only.

| 3
Model FT3
Table of Contents

1. Introduction p. 6-20

a. Quick Start Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 6

b. Menu Trees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 8

c. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 17

2. Installation (Mechanical) p. 20-33

a. Lateral Placement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 21

b. Welding Branch Outlet to Pipe (Insertion) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 23

c. Installation Depth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 24

d. Orientation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 25

e. Mounting Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 27

f. Retractor Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 29

3. Wiring (Electrical) p. 33-49

a. Wiring Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 33

b. Input Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 36

c. Signal Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 38

d. Alarm Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 40

e. Remote Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 43

f. Remote Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 48

4. Operation (Standard Operation) p. 50-89

a. Start Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 50
b. Display Screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 51

c. Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 53

5. Communications p. 90-105

a. Modbus Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 90

b. Modbus Communication Protocol and Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 99

c. HART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 101

d. HART Communication Protocol and Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 102

| 4
 Model FT3
Table of Contents

6. Data Logger p. 106-111

a. Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 106

b. Setup Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 106

c. Clearing the Data Log . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 107

d. Setting the Start/Sync Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 108

e. Setting the Real Time Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 109

f. Viewing the Real Time Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 110

g. Displaying Data Log Records . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 111

7. Maintenance p. 112-121

a. Safe Meter Removal from Retractor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 113

b. Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 116

c. Installation Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 118

d. Calibration Validation Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 119

e. Alarm Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 120

8. Appendices p. 122-139

a. Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 122

b. Agency Approvals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 125

c. Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 126

d. Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 135

e. Returning your meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . p. 136

9. Definitions p. 137

10. Index p. 138

| 5
Model FT3
Quick Start Guide

Use the table below as a guide while using the worksheet on the next page to record your notes.
NOTE! Please read the entire quick-start procedure before beginning installation.

1. Record inside diameter (ID). Ensure the actual pipe ID

matches the pipe ID shown on the factory calibration
Outer
certificate. If IDs do not match, refer to "Pipe Area" on ID Diameter
page 68. (OD)
2. Pipe ID min.
Record up/downstream straight-pipe requirements
based on Pipe ID and meter style (insertion or inline). FLOW
FLOW
[refer to p. 21] 8X = Inline 4X = Inline
MODEL FT2A
Gas Mass Flowmeter & Temperature Transmitter

15X = Insertion 10X = Insertion

3.
INDICATOR:
The Flow Direction Indicator must point in the - POINT IN DIRECTION
direction of flow. OF FLOW

4. PIPE
Ensure correct probe depth setting. If using 1 ½" size
pipe, please see note on p. 24. CL FLOW

Earth Ground

5. TS2
Red2
Red 1
Earth Ground
TS3

Ensure power wiring [p. 36] properly connected.

REMOTE Yel 3
4-20
+1
SENSOR Wh 4
24V Return
FLOW

[refer to Wiring section p. 33 for more information]

-2
+3
Wh 5 +24VDC
4-20
#2 1 2 3
-4
TS1
+5 Shield
PULSE
/ALM #4
-6

6.
+7
IN
Cable Shield
F1
-8 TS4 -2 +1 GRN
24V 24V, 0.75A #6 W

Ensure remote wiring is correct if remote option

OUT RED
RED 1
BLK
TS

RED 2
5

ordered.
J2 BRN BRN
YEL 3 #3
WHT

[refer to p. 48 for more information]

WHT 4
GRN
WHT 5

TS3
1 2 3
TS1
FT3 Customer PLC or DCS

7.
Red 1
TS2
Red2 F1
+24VDC
-2 +1 TS3
TS4 REMOTE Yel 3
SENSOR 24V,0.75A
+1
24V 4-20 Wh 4 4 to 20mA FLOW RATE
OUT

Verify you have the proper output signal wiring

FLOW
-2 Wh 5 * (see important note below)
+3
4-20
#2 -4 J2 1 2 3
24VDC Return

[refer to p. 38 - p. 45 for more information]

TS1
+5
PULSE
/ALM
-6 +24VDC
+7 F1
IN

Electronics Enclosure
TS4 +1 -2
-8 24V 4 to 24V,
20mA TEMPERATURE OR
0.75A
FLOW RATE
SENSOR
OUT
* (see important note below)
J2
24VDC Return
R

8.
Power on the flow meter.
Initializing...

9. Check the remaining flow meter settings by accessing the meter settings eitherF1through
F2 F3 F4 the front panel

of the display or by using the FT3 View™ software tool. Record the settings in the spaces given for
items A - E on the following page.

Ouick Start Guide | 6

 Model FT3
Quick Start Guide

Before powering on your meter, use this worksheet to record your notes.

Serial Number: Serial Number: Serial Number: Serial Number:

Item to verify
1. What is the Pipe ID? ID = ID = ID = ID =

2. Calculate the Upstream/ UP = UP = UP = UP =

Downstream straight-pipe DN = DN = DN = DN =
requirements
3. Is the flow indicator pointed in Y/N Y/N Y/N Y/N
direction of flow?
4. Is the probe depth setting correct? Y/N Y/N Y/N Y/N

5. Verify proper power wiring

6. Verify proper remote wiring (if

ordered)
7. Verify proper input/output wiring

After powering on your meter, check items A - E below by accessing the meter settings either through the
front panel of the meter's display or by using the FT3 View™ software tool.
A. Which flow units have been set in
meter? (SCFM, KG/H, etc..)
B. Correct values for reference Y/N Y/N Y/N Y/N
temperature and pressure?
C. Confirm the pipe ID listed above
same as "Pipe_id="
D. Verify the 1st 4mA and 20mA 4mA = 4mA = 4mA = 4mA =
meter settings 20mA = 20mA = 20mA = 20mA =
E. Verify the 2nd 4mA and 20mA 4mA = 4mA = 4mA = 4mA =
meter settings 20mA = 20mA = 20mA = 20mA =
Your Notes:

If you are experiencing any problems after completing this procedure, please call the Fox
Thermal Service Department at 831-384-4300 to review this information.

Ouick Start Guide | 7

Model FT3
Introduction

Fig. 1.1: FT3 Menu Tree - Main Menu

Enter menu by scrolling to display 6

and entering the password

SET PARAMETERS
I/O FLO DSP EXIT

Display Menu, p. 12
Flow Parameter Menu 1, p. 10

SET I/O
COM I/O 420 EXIT

Analog Outputs

SET I/O SET 4-20 mA

INP OUT LOG EXIT CH1 CH2 EXIT Select either flow
or temperature for
channel 2
None
Modbus
Comm=Modbus
HART NXT OK
20 mACnt=3265
Not used INP= Not used Temp CH2=Temp
Tot Reset CHG OK
NXT OK Flow NXT OK
Level 2
password
4 mACnt=367
1200
2400 Baud=9600 CHG OK
4800 NXT OK
9600 20mACnt=3748
19200
CHG OK
20 mA=2345.6 SCFM Level 2
NONE
Parity=EVEN Modbus CHG OK password
ODD
EVEN NXT OK only
4mACnt=274
CHG OK
4 mA=0 SCFM
01-247
Address=02 CHG OK
CHG OK
20 mA=300 °F
CHG OK
Not use mA Fault=Not use
3.6 mA
21 mA NXT OK

4 mA=0 °F
CHG OK

Data Log Menu, p. 14

Digital Output Menu, p. 9

NOTE! Some menus will only be available with a level 2 password.

NOTE! Menu tree boxes are populated with example values.

Introduction | 8
 Model FT3
Introduction

Fig. 1.2: FT3 Menu Tree - Digital Outputs and Input

Not used
Frequency OUT= Not used
HiFloAlm NXT OK
LoFloAlm
HiTempAlm
LoTempAlm Frequency
System Alm

Select 1 of 3
High Limit Alarm OUT= FREQUENCY methods to scale
NXT OK the frequency
output
OUT= HiFloAlm
NXT OK
FREQUENCY OUTPUT
P/U U/P FEQ EXIT

HiFloAlm=500 SCFM
CHG OK

PLS/UNT=2 UNT/PLS=0.5 MaxFreq=100Hz

CHG OK CHG OK CHG OK
Low Limit Alarm

OUT= LoFloAlm
NXT OK MaxFlo=5678.5 SCFM
CHG OK

LoFloAlm=100 SCFM
CHG OK

High Temp Alarm

OUT= HiTmpAlm
NXT OK

HiTmpAlm=300° F
CHG OK

Low Temp Alarm

OUT= LoTmpAlm
NXT OK

(See Flow Parameter 2, p. 11, for more alarm

LoTmpAlm=10 F
CHG OK settings)

System Alarm

OUT= SYSTEM ALM

NXT OK

NOTE! A value of 0 disables the alarms

Introduction | 9
Model FT3
Introduction

Fig. 1.3: FT3 Menu Tree - Flow Parameter 1

FLOW PARAMETER 1 Flow Parameter 2 Menu, p. 11

DGN UNT PRM EXIT

DIAGNOSTIC SCFM FLO UNT=SCFM

SCFH
SIM TST EXIT NM3/H NXT OK
NM3/M
KG/H STP
KG/M
KG/S
LBS/H Deg F TMP UNT=° F
Simulate Flow? LBS/M Deg C NXT OK
YES NO LBS/S
NLPH
NLPM
SMPS
NMPS TmpRef= 0 °F
FloSim=0 SCFM SFPM CHG OK
MMSCFD
CHG OK LBS/D
SLPM
NLPS
MSCFD mmHG PRES UNT=mmHG
Simulate Temp? SM3/H
MT/H
Psia NXT OK
YES NO bara
NM3/D
MMSCFM
SCFD
MCFD
PresRef=760
SM3/M
TmpSim=0 ° F SM3/D CHG OK
CHG OK

Simulate CSV?
YES NO
Diagnostic Test Menu, p. 13

CsvSim=0 V
CHG OK

ENABLE SIM?
YES NO

Note: simulation
value needs to be
greater than zero
to be taken
(i.e 0.0001 for a
value close to
zero)

Introduction | 10
 Model FT3
Introduction

Fig. 1.4: FT3 Menu Tree - Flow Parameter 2

FLOW PARAMETER 2
CAL SPC PRM EXIT

Level 2 Level 1
Calibration Table Parameters

CAL TABLE K fact = 0% Cutoff=12.5 SCFM Flow cutoff in selected unit

TB1 (TB2) (TB3) EXIT CHG OK CHG OK

A2=0.0233 Pipe Area in m2 or �2

RESTORE DATABASE? Level 2
CHG OK
YES NO password
sensor voltage
for point #1
Filter=0.8 Flow Exponen�al Filter
RESET CRC? CHG OK
Volt1 = 0.2479 YES NO
CHG PRV NXT EXIT
HiFloAlm=0 SCFM High Flow Alarm in selected
CHG OK unit

Flo1 = 0.0
CHG PRV NXT EXIT LoFloAlm=0 SCFM Low Flow Alarm in selected
CHG OK unit
velocity in Meter/
hour for point #1
HiTempAlm=0 °F High Temperature Alarm in
CHG OK selected unit
Volt20 = 1.2479
CHG PRV NXT EXIT
LoTempAlm=0 °F Low Temperature Alarm in
CHG OK selected unit

Flo20 = 7046.5
CHG PRV NXT EXIT

Cycle through
up to 20 settings

NOTE! Some menus will only be available with a level 2 password.

Introduction | 11
Model FT3
Introduction

Fig. 1.5: FT3 Menu Tree - Display Menu

DISPLAY/PASSWORD
DSP IR PSW EXIT

Display 1
Line 1

FLo rate Enabled

Total
DSP1L1=FLo rate Disabled
IR KEY=Enabled PASSWD=1234
Elps NXT OK NXT OK CHG OK
Display 1 Temp
Line 2 Alarm

FLo rate
Total
DSP1L2=Temp
Elps NXT OK
Display 2 Temp
Line 1 Alarm

FLo rate
Total
DSP2L1=Alarm
Elps NXT OK
Display 2 Temp
Line 2 Alarm

When alternate
FLo rate
DSP2L2=Elps "ON", flashes
Total
Elps NXT OK between the 2
Temp displays
Alarm

On
Off
ALTERNATE=Off
NXT OK

NOTE! All readings updated every second

• Flo Rate = Flow rate of process gas
• Total = Total flow of process gas
• Elps = Elapsed time since reset of flow total
• Temp = Temperature of process gas
• Alarm = Notification of errors; diagnostic errors

Introduction | 12
 Model FT3
Introduction

Fig. 1.6: FT3 Menu Tree - Diagnostic Tests Menu

DIAGNOSTIC
CALV ZRO EXIT

CAL Display alternates ZERO CHK MENU

VER EXIT between the 2 PIP BTL EXIT
screens until the
Level 1 test is completed
Hold Value
in about 4
Flo:Go to zero minutes. Pressing
Go to zero
NXT EXIT OK the F4 key will
abort the test ZERO PIPE TEST
VER SET PRM EXIT
Take Control
off-line EXIT OK

Level 1 Level 2 Level 2

VERIFY ZRO? SET ZRO Ref? Test=300 sec
Verifying CAL-V Verifying CAL-V YES NO YES NO CHG OK
Please Wait Cal=xxx T=yyy

Process Zero and Process Zero and

Stable? EXIT YES Stable? EXIT YES Displays count
CAL-V=0.51
down timer
Pass OK
(T=xx)
Setting ZRO ref
Verifying ZRO Verifying ZRO ZR=x.xxxxx T=xx
Diff=x.xx T=xx Sd=x.xe-xx T=xx
“Pass” or ”Fail”
result is displayed Ref=x.xxxx
at end of test. OK
Diff=x.xxx %
Display Pass OK
alternates
between
the 2
screens ZERO BTL TEST
Displays VER EXIT
“Pass” or
“Fail”

Level 1
VERIFY ZRO?
Display
YES NO
alternates
Flow Parameter 1 Menu, p. 10 between
the 2
screens Process Zero and
Stable? EXIT YES

Verifying ZRO Verifying ZRO

Diff=x.xx T=xx Sd=x.xe-xx T=xx

Displays “Pass” or
“Fail” Diff=x.xxx %
Pass OK

NOTE! Some menus will only be available with a level 2 password.

Introduction | 13
Model FT3
Introduction

Fig. 1.7: FT3 Menu Tree - Accessing Data Logger Functions from the Front Panel

SET I/O
INP OUT LOG EXIT

ON Data log = ON
OFF NXT OK
Clear Log?
Level 2
YES NO
Level 1

DATA LOG
CLR STR TIM EXIT DATA LOG
INT STR TIM EXIT

Set Interval Set Start Time

Day Int = 0 ON Start Time = ON

0-30
CHG OK OFF NXT OK Date / Time
Set View EXIT
Set Time View Time
Hour Int = 0 1-31 Day Start = 0
0-24 0=default
CHG OK CHG OK
Year Set = 13
CHG OK
Date / Time
Min Int = 1 0-59 Hour Start = 13 8/10/13 8:29:36
0-60
CHG OK CHG OK Month Set = 10
CHG OK

0-59 Min Start = 5 Day Set = 7

Set Interval? CHG OK CHG OK Display
YES NO Date and
Hour Set = 10 Time
CHG OK every
Set Start Time? second
All entries in “Set Interval” YES NO until F4 is
are converted into a minute Min Set = 5 pressed
interval counter. CHG OK
When “Start Time” is
detected, the interval is
Sec Set = 0
reloaded to re-sync in the
CHG OK
event that the power has
been lost. Day entry set to 0
is the default. For a midnight
re-sync, all values should be
set to zero. Set Date / Time?
YES NO

Time will
be set
when the
YES key is
pressed

Introduction | 14
 Model FT3
Introduction

Fig. 1.8: Viewing Data Logger Records from the Front Panel

Use the F2 key to move to Use the F4 key to exit

the next record, to normal mode
Use the F1 key to move
F1 AND F4 keys pressed back to the previous one. F1 AND F3 keys pressed
at the same time Use the F4 key to exit to at the same time
normal mode

Data log Record # is displayed Date and Time

for 1 second refreshed every second

Data log Rec #1 Date / Time

8/10/13 8:29:36
Record # 1 is the latest data,
Record #31 the oldest
Note: Seconds displayed only if
8/10/13 09:53 there is enough room on display
ITot = 7034691.2

Data log Rec #2

8/10/13 09:53
ITot = 7034691.2
F1 Key F2 Key

Data log Rec #30

8/10/13 09:53
ITot = 7034691.2

Data log Rec #31

8/10/13 09:53
ITot = 7034691.2

Introduction | 15
Model FT3
Introduction

Fig. 1.9: FT3 Menu Tree - Engineering Displays

Enter Log Menu: Press F1 & F2 at the same time

Flow in selected unit 3124.6 SCFM Enter: Press F1 & F2 at the samePress
timeF4 to return to normal mode
Display 10
Sensor voltage in volts csv=0.3432 Volt Press F4 to return to normal mode
Sensor average volts CsvAv=366809
Display 11 LOG MENU 1
Velocity in selected unit Vel=112345.7 FT/M
LOG TOT ENG EXIT
Sensor filtered average in volts FloFlt=3666805.3
Display 12
Velocity in Meter/Hour Vel=2356.45 M/H

TSI average count TsiAvr=512.5 cnt

Display 13
TSV average count TsvAvr=323.7 cnt Day1=0 SCF
D
NXT PRV EXIT
TSI in volts Tsi= 2.1345 Volt
Display 14
TSV in volts Tsv=0.9856 Volt
D
TSI current in Amp Tsi = 0.0435 Amp
Display 15
TSI resistance in Ohm Tsi = 221.5 Ohm 40 24‐hour totals listed
D
RTD9 count RTD9= 345.5 cnt
Display 16
Gas Temperature in C Gas Temp=123.7 °C
D
CH1 4-20ma current loop count CH1_420=2167 cnt Day40=0 SCF
Display 17
CH2 4-20 ma current loop count CH2_420=1234 cnt
F1 Key F2 Key
NXT PRV EXIT
D
Frequency output count Feq=1234.5 cnt
Display 18
Alarm codes Alarm=33,35
D
High flow limit alarm FloHi= 1234 SCFM
Display 19
Low flow limit alarm FloLo=0 SCFM
D
High temperature limit alarm TmpHi=300 °C
Display 20
Low temperature limit alarm TmpLo=10 °C
D
Elapsed time in hour Elp=12.5 HR
Display 21
Status in hexadecimal Stat(hex)=2800
D
FT3 main board firmware revision FT3 V3.13
Display 22
FT3 display board firmware revision Display V3.05
D
Power cycle count Pwr_Cycl=24
Display 23
Error with totalizer count Err_tot=0

TSI resistance in ohm Tsi=221.5 Ohm

Display 24
RTD9 resistance in ohm RTD9=10.3 Ohm

CAL-V™ Value CAL-V=23.51

Display 25
CAL-V™ last verify value CAL-V Chk=0.2%

BrShtDnCnt=0 cnt
Bridge shutdown detection count Display 26

Zero CAL-CHECK® Pipe Ref ZRO_Pref=xx.xxxx

Display 27
Zero CAL-CHECK® % difference ZRO_diff=x.xx%

Zero CAL-CHECK® Bottle Ref ZRO_Bref=xx.xxxx

Display 28
Zero CAL-CHECK® % difference ZRO_diff=x.xx%

F3 & F4 pressed at the same time will

initiate a "Total" reset

Reset Total?
NO YES

Resetting Total

Introduction | 16
 Model FT3
Introduction

Welcome
Thank you for purchasing the model FT3 thermal gas mass flow meter from Fox Thermal. The FT3 is
one of the most technically advanced flow meters in the world. Extensive engineering effort has been
invested to deliver advanced features, accurate measurement performance and outstanding reliability.

This instruction manual contains the electrical and mechanical installation instructions as well as
details for programming, maintaining and troubleshooting the meter. This manual is divided into the
following sections: Introduction, Installation, Wiring, Operation, Communications,
Data Logger, Maintenance, Appendix, Definitions, and Index.

Theory of Operation
The model FT3 is an innovative thermal mass gas flow meter and temperature transmitter. It is
microprocessor-based and field programmable. The FT3 thermal sensor operates on the law that
gases absorb heat. A heated sensor placed in an air or gas stream transfers heat in proportion
to the stream’s mass velocity. There are two sensor elements. One sensor element detects the
gas temperature and a second element is maintained at a constant temperature above the gas
temperature. The energy transferred from the heated element is proportional to the mass flow
velocity. The FT3 flow meter maintains accurate flow measurement over a large temperature and
pressure range.

Mass Flow
The model FT3 measures mass flow; an advantage over other flow meters which measure volumetric
flow rate. Volumetric flow is incomplete because temperature and pressure are unknown and must be
measured separately. For example, the mass flow of a gas depends on its temperature and pressure.
As temperature and pressure changes, the gas volume changes but not its mass. Therefore a device
measuring mass flow is independent of temperature and pressure changes. The model FT3 provides
a direct measurement of gas flow in mass units (kg/hr, lb/hr), standard units (SCFM, SLPM) or normal
units (NM3/hr, NLPM) with no additional temperature or pressure measurements required.

Calibration Validation
Fox Thermal has developed a method to validate the calibration of the flow meter in the field. This
method is called Calibration Validation and it is made up of two distinct tests: CAL-V™ and Zero CAL-
CHECK™. The goal of Calibration Validation is to provide operators with the ability to verify that the
meter is capturing accurate data at scheduled recalibration times - or at any time - instead of sending
the meter back to the factory for recalibration.

By performing CAL-V™ in the field, operators can verify that the meter is running accurately by testing
the functionality of the sensor and its associated signal processing circuitry. This test can be done
in the pipe and in normal processing conditions. The second test, Zero CAL-CHECK™, ensures the
effectiveness and sensibility of the sensor at a "no flow" condition.

Flow Calibration
Every Fox Thermal flow meter is set to the customer's configuration at the factory using an App ID
which is generated by the on-line configurator. The App ID specifies the gas type, flow range, serial
communication and other settings in the meter. If these settings match the final customer application,

Introduction | 17
Model FT3
Introduction

the meter is ready to use. The Fox Thermal Calibration Lab maintains instrument calibration data on
every flow meter. Calibration files include details on process conditions, customer gas, line size and
other information. All NIST-traceable equipment utilized for the calibration procedure is identified on
the Calibration Certificate, which is sent with every flow meter.

I/O Description
The FT3 features two galvanically isolated 4-20mA analog outputs, one isolated digital output that
can be used for pulse output or alarm, one programmable contact input, and a USB connection for
communication with a computer.

The first 4-20mA output is for flow rate. The second 4-20mA output can be configured either for
flow rate or process gas temperature. Both 4-20mA outputs can be scaled by the user. The pulse
output is programmable to represent flow rate and can be scaled for maximum flow/maximum
frequency, units-per-pulse or pulse-per-units. The maximum frequency is 100 Hz. An isolated 24VDC
output power option is provided for use with these outputs. It can supply a 42mA maximum total load
(do not use for other external devices). FT3 View™ interfaces to the USB port and is a free Fox Thermal
PC-based software program available for download on the Fox Thermal website. FT3 View™ displays
flow meter readings and permits flow meter configuration. Industry standard communication options
are available including HART or Modbus RTU (RS485). Only one of these options can be provided in a
single FT3 flow meter.

FT3 Optional Display and Configuration Panel

The configuration panel allows the user to change a variety of settings in the FT3. The display is 2
lines x 16 characters with 4 mechanical and 4 IR (infrared) keys. The IR and mechanical (push) buttons
perform the same function but the IR keys can be used without opening the cover. The IR keys can
be calibrated for better operation in the field or disabled when the meter is used in snow or ice in
order to avoid false key detection (see p. 89).

Fig. 1.11: FT3 Optional Display and Configuration Panel

Display Window
F1 F2 F3 F4
IR (infrared) Buttons

Push Buttons

Introduction | 18
 Model FT3
Introduction

FT3 Functional Diagram

An on-board 2 line x 16 character backlit LCD display shows flow rate, total flow, elapsed time, process
gas temperature, and alarms. The display is also used in conjunction with the Configuration Panel for
field configuration of flow meter settings such as 4-20mA scaling, pulse output scaling, pipe area, zero
flow cutoff, flow filtering or damping, display configurations, diagnostics, and alarm limits.

Fig. 1.11: FT3 Function Diagram

Standard I/O
24VDC Input Power
100-240VAC Optional 4-20mA Flow

4-20mA Flow or Temperature

Optional Display and
Configuration Panel F1 F2 F3 F4
Pulse or Alarm Output

Contact Input

Standard Digital Communications

USB
(Free FT3 View™ Software)

Optional Serial Communications

HART

Modbus RTU (RS485)

Outputs and Communications are Galvanically Isolated

Introduction | 19
Model FT3
Installation

Installation Scope
This section describes how to install the Fox Thermal model FT3 Flow Meter and how to get started.
Installation methods will vary according to the flow meter type (insertion or inline).

For Insertion Types:

1. Determine lateral position on the pipe.
2. Determine radial position of probe if moisture or condensation present in the gas.
3. Sensor installation depth.
4. Sensor orientation in relation to sensor length and direction of flow.
5. Proper tightening of compression fitting for mounting meter.

For Inline Types:

1. Determine lateral position on the pipe.
2. Flow body orientation in relation to direction of flow in pipe.
3. Proper tightening of compression fitting.

Installation procedures must be performed using a combination of the end user’s best engineering
practices, in compliance with local codes, and with manufacturer’s recommendations.

General Precautions
The following general precautions should be observed:
1. Exercise care when handling the flow meter to avoid damaging the probe, sensor or
enclosure.
2. Close any unused conduit openings in the enclosure with plugs certified for your
application.
3. The enclosure cover must be closed except during configuration or during installation.
4. Mounting FT3 in direct sunlight can cause the temperature inside the enclosure to increase
beyond design limits, resulting in failure of LCD display and reduced component life. It
is recommended that a sunshade be installed to avoid direct sunlight (see maximum
enclosure operating temperature specification).
5. Ensure the flow direction indicator points in the direction of flow.
6. Do not install the FT3 enclosure near an igniter, igniter-controller or switching equipment.
7. Do not install an external power supply in a cabinet containing an igniter controller or
switching equipment.
8. For accurate flow measurement, review flow meter placement instructions before
installation to ensure a proper flow profile in the pipe.
9. For safety reasons, Teflon ferrules are only appropriate for applications with pressures of 60
psig or less. At higher pressures, use of a Teflon ferrule risks unwanted probe movement
or ejection of the probe from the pipe. For all applications above 60 psig, the standard
stainless steel ferrule is required.

Installation | 20
 Model FT3
Installation

Instructions for Flow Meter Lateral Placement

Install the model FT3 flow meter so that it is far enough away from bends in the pipe, obstructions, or
changes in line sizes to ensure a consistent flow profile. See Fig. 2.1 below for your meter type.
Fig. 2.1: Upstream and Downstream Pipe IDs for Insertion and Inline Flow Meters

Irregular
INSERTION
Profile Branch Outlet
Proper F1 F2 F3 F4

(installed by
Profile customer)

FLOW

15X Pipe ID 10X Pipe ID

INLINE
Irregular
Proper
Profile
F1 F2 F3 F4

Profile

FLOW

8X Pipe ID 4X Pipe ID

INSERTION WITH FC20

FC20 Flow Conditioner
installed between two flanges
Proper Branch Outlet
Flow (installed by customer)
Profile
Irregular Flow F1 F2 F3 F4

Profile

FLOW

5X Pipe ID min. 2x 5X Pipe ID min.

Pipe ID

NOTE!
• Pipe ID = Inside Diameter
• The probe diameter is ½"
• An irregular flow profile will affect sensor accuracy
• See FC20 Installation Instructions (PN 109193) for more information

Installation | 21
Model FT3
Installation

Radial Probe Position - Moisture in the Gas or Condensation

The radial position of the meter may help reduce collection of moisture on the sensor. Condensing
liquids contacting the meter's sensing elements will disrupt accurate flow measurement. Fox Thermal
recommends the flow meter be used in dry gas conditions whenever possible for highest accuracy.
Contact Fox for further recommendations.

Fig. 2.2: Installation at 180° and 45°

F1
F2
F3
F4
F1 F2 F3 F4

Alternate Installations - Vertical Pipes or Restricted Installation Spaces

When restricted physical installation space exists, the FT3 can also be installed at other angles. Please
note that the display and the enclosure orientation can be rotated in 90º increments.

Fig. 2.3: Alternate Installation at 90° (CCW)

F1 F2 F3 F4

"D5/D6" Display Configuration Code

NOTE! Displays are rotatable only in 90° angle increments.

Installation | 22
 Model FT3
Installation

Welding Branch Fitting to Pipe

The probe of the FT3 must be installed perpendicular in the pipe to measure flow accurately. Use the
following steps to ensure that the ¾" branch fitting is correctly welded to the pipe.
Directions:
1. Drill a 0.531" (17/32") hole inside the fitting through the wall of the pipe (1 wall only).
2. Assemble the compression fitting and branch fitting hand tight onto the probe of the FT3.
3. Insert the probe into the hole in the pipe and use the FT3 probe and compression fitting to align
the branch fitting with the hole and the probe perpendicular to the pipe.
4. Tack-weld the branch fitting carefully onto the pipe.
• Before welding the fitting completely, verify the probe is aligned to the center of the pipe and
the hole is centered in the branch fitting (see Fig. 2.4).
5. To verify that the correct hole position has been achieved, carefully slide the 0.50" sensor in and
out of the branch fitting and 0.531" hole.

WARNING! Do not force the 0.50" sensor through the 0.531" hole. Forcing it through the
hole can damage the probe!

6. Verify that the temporary weld of the branch fitting positions the probe window on the pipe's
centerline.
• Fig. 2.4 shows an incorrect welding of the branch fitting, causing the 0.50" sensor to be "off
center".
7. Once the branch fitting is aligned properly, remove the 0.50" sensor from the branch fitting and
finish welding. Then verify the probe is still aligned with the center of the pipe.
8. Set the depth of the flow meter (see "Fig. 2.5: Insertion Sensor Depth in Pipe" on page 24).
• Do not tighten compression fitting until proper depth of flow meter is determined.

Fig. 2.4: Alignment of Branch Fitting

INCORRECT
BRANCH, FEMALE,
CORRECT BRANCH, FEMALE, 3/4" NPT
3/4" NPT

DIA. 0.531 DIA. 0.531

DIA. 0.500 HOLE HOLE
PROBE DIA. 0.500
PROBE

CENTERED
OFF CENTER
PIPE PIPE

PIPE PIPE
CENTERLINE CENTERLINE

Installation | 23
Model FT3
Installation

Installation Depth
The installation depth of the sensor in the pipe is dependent on the pipe size. To get the most
accurate reading, the sensor window must be properly positioned within the pipe.

When installing the latest 45° sensor design, the end of the sensor should be 0.73" (18.5 mm) past the
center of the pipe.

When installing an original sensor design, the end of the sensor window should be 0.87" (22.1 mm)
past the center of the pipe. Reference sensor design figures on page 26.

Review Fig 2.5 below and use the following equations to calculate insertion depth. Insertion depth is
measured from the top of the compression fitting to the bottom end of the probe.
For latest 45° sensor design, Insertion depth = L +D/2 + 0.73"
For original sensor design, Insertion depth = L +D/2 + 0.87"

CAUTION! For a 1½" pipe, do not tighten compression fitting without 0.2” distance from wall
or damage to probe will occur.

Fig. 2.5: Insertion Sensor Depth in Pipe

F1 F2 F3 F4

Probe Diameter, 1/2”

Compression Fitting
(Supplied by Fox)

Branch Fitting,
3/4" NPT Female
(Supplied by
“L” Customer)

INSERTION DEPTH

“D/2”

CL

45° Sensor Design: 0.73” (18.5 mm)

Original Sensor Design: 0.87” (22.1 mm)

“D”

Installation | 24
 Model FT3
Installation

Direction of Flow and Orientation of the Probe

Install the meter with the flow direction indicator pointing in the direction of flow and centered on
the middle of the pipe. The rotational misalignment of the flow direction indicator must be less than 2
degrees.

Fig. 2.6: Orientation of Flow Meter

TOP VIEW

Pipe Note: Rotational misalignment

should not exceed ±2°
+2°

FLOW

-2°

FRONT VIEW

F1 F2 F3 F4

Flow Direction Arrow

Pipe

FLOW

NOTE! Some flow meters are shipped with the sensor elements that are offset (see Fig. 2.7).
Others are shipped with sensors that have equal length elements (see Fig. 2.8). The sensor
type supplied was selected at the factory to be the best suited for your application. Follow the
appropriate sensor orientation instructions.

Installation | 25
Model FT3
Installation

Sensor Orientation - Latest 45° Design

The sensor element tubes of the latest sensor design are connected at both ends and offset at 45
degrees in relation to the sensor window opening. Install the flow meter with the window opening
facing the flow stream within ±2°.

Fig. 2.7: Latest Design 45° Sensor Elements

+2°

FLOW
-2°

FLOW

Sensor Orientation - Original Design

Unequal Length Sensor Elements - Install the shorter element upstream from the longer one.
Equal Length Sensor Elements - Install flow meter with both sensor elements facing the flow stream
within ±2°.

Fig. 2.8: Equal and Unequal Length Sensor Elements

+2° -2° +2° -2°

FLOW FLOW

FLOW FLOW

Equal Length Sensor Elements Unequal Length Sensor Elements

Installation | 26
 Model FT3
Installation

Mounting Instructions - Compression Fittings

FT3 insertion style flow meters are mounted through a 0.531" (17/32") hole and a ¾" female NPT
branch outlet in the customer's pipe. Insertion style flow meters are not designed for use in pipes
smaller than 1½".
• Install the compression fitting into the ¾" female NPT branch outlet.
• When installing the probe in a 2" pipe or larger, use the installation depth instructions (refer to
Fig. 2.5).
• When installing into a 1½" pipe, carefully install the probe into the pipe until it touches the
opposite wall and pull back 0.2".
• Rotate the nut finger-tight.
• Further tighten the nut just enough until the tube will not turn by hand or move axially in the
fitting.
• Mark the nut at the 6 o'clock position.
• While holding the fitting body steady, tighten the nut one and one-quarter (1 ¼) turns to the 9
o'clock position. See Fig. 2.9.

Fig. 2.9: Proper Tightening of the Compression Fitting Nut

NOTE! Before removing a probe with compression fitting, mark the tube at the back of the
nut, and mark a line along the nut and fitting body. Use these marks when reinstalling the
probe. Reference the instructions on p. 28.

NOTE! When installing a probe with compression fitting that has been tightened previously,
use the instructions on Page 28.

CAUTION! Once the compression fitting is locked onto the probe, the probe can be
removed or rotated, but the insertion depth is locked in place.

CAUTION! For a 1½" pipe, do not tighten compression fitting without 0.2” distance from
wall or damage to probe will occur.

CAUTION! If the stainless steel or Teflon ferrules are not properly tightened, and/or the
recommended pressure is exceeded, the ferrules can slip on the stainless steel tubing
causing damage to the meter or bodily harm.

Installation | 27
Model FT3
Installation

Mounting Instructions - Compression Fittings (Inline and Insertion Meters Previously Installed)
In cases where a compression fitting has already been swaged in an inline flow body or an insertion
meter, use the following procedure.
• Carefully insert the probe with swaged ferrules into the fitting until the front ferrule seats
against the fitting (see Fig. 2.10).
• Verify that the probe is installed the correct depth in the pipe (refer to Fig. 2.5).
• Rotate the nut with a wrench until the probe and nut are in their previously marked positions,
or you feel a significant increase in resistance (see Fig. 2.10).
• Tighten the nut slightly (approximately 1/8 turn).

Fig. 2.10: Proper Re-Tightening of the Compression Fitting Nut

CAUTION! Do not use a gap inspection gauge with reassembled fittings.

Installation | 28
 Model FT3
Installation

Installation of a New Retractor Assembly

1. Remove meter probe from retractor assembly and leave the ball valve open.
2. Install the valve assembly on the pipe, by tightening the Hex Nipple with a 1-1/16" wrench.

Fig. 2.11: Retractor Assembly Without Probe Installed

NUT & FERRULES

COMPRESSION
FITTING RETRACTOR

HEX NIPPLE

RETAINING
RING BRANCH WELD FITTING,
3/4" NPT, 316 SST

Installation | 29
Model FT3
Installation

3. Carefully slide the probe through the retractor assembly and through the hole to see if there is
interference by touching the pipe wall with the end of the probe on the far side or until the probe
cannot go deeper. Remove the probe. Remove the retractor and rework the hole, if required.

Fig. 2.12: Verify Probe Insertion

METER

RETRACTOR

4. The installation depth of the sensor in the pipe is dependent on the pipe size. To get the most
accurate reading, the sensor window must be properly positioned within the pipe.

When installing the latest 45° sensor design, the end sensor should be 0.73" (18.5 mm) past the
center of the pipe.

When installing an original sensor design, the end of the sensor window should be 0.87" (22.1
mm) past the center of the pipe. Reference sensor design figures on page 26.

Installation | 30
 Model FT3
Installation

Review Fig 2.13 below and use the following equations to calculate insertion depth. Insertion
depth is measured from the top of the compression fitting to the bottom end of the probe.
For latest 45° sensor design, Insertion Depth = L + D/2 + 0.73"
For original sensor design, Insertion Depth = L +D/2 + 0.87"

CAUTION! For a 1½" pipe, do not tighten compression fitting without 0.2” distance from wall
or damage to probe will occur.

5. The Retractor Clearance table of Fig. 2.13 lists the space required to remove the meter from the
retractor. Use the model code of your meter to determine the dimension.

Fig. 2.13: Determining and Marking Insertion Depth

"RC"
RETRACTOR
CLEARANCE
MARK ON
PROBE

"L"
INSERTION
BRANCH WELD FITTING, DEPTH
3/4" NPT, 316 SST

"D/2"
"D"

45° Sensor Design: 0.73” (18.5 mm)

Original Sensor Design: 0.87" (22.1 mm)

RETRACTOR CLEARANCE
CODE "RC" DIMENSION
15R 27.3" (69.4 CM)
18R 30.3" (77.0 CM)
24R 36.3" (92.2 CM)
30R 42.3" (107.4 CM)
36R 48.3" (122.7 CM)

Installation | 31
Model FT3
Installation

6. Insert probe back into the retractor to the depth mark and hand-tighten the compression fitting.
7. Verify that flow direction indicator is in line with pipe and in the direction of flow.

Fig. 2.14: Installed Retractor

FLOW DIRECTION
ARROW
NUT

COMPRESSION
FITTING

8. Fully tighten compression fitting (refer to the instructions on p. 27).

NOTE! For instructions on how to properly remove and replace the meter from a retractor, please
refer to "Instructions for Removing and Inserting the Meter from a Pressurized Pipe using the
Retractor" on page 113.

Installation | 32
 Model FT3
Wiring

Wiring Instructions
To wire the FT3 connect the power and signal wires to the terminal blocks according to the label and
instructions on the following pages.

Fig. 3.1: FT3 Wiring Access

Front Enclosure Cap Rear Enclosure Cap

No Wiring Access Wiring Access
Unscrew front enclosure cap to access the Unscrew the rear enclosure cap to access wiring
mechanical buttons or change the orientation of terminals for power, 4-20mA and pulse outputs,
the display and configuration panel. switch input, USB port, remote sensor, and serial
communication options.

Earth Ground

F1 F2 F3 F4

Red 1
TS2
Red2
TS3
+1 REMOTE Yel 3
4-20 SENSOR Wh 4
FLOW
-2 Wh 5
+3
Display front 4-20
#2 1 2 3
panel -4
TS1
+5
PULSE
/ALM
-6
+7 F1
IN TS4 -2 +1
-8 24V 24V, 0.75A
OUT

J2

USB port

Wire the FT3 by opening the rear enclosure cover, bringing customer supplied wires in through
the conduit openings and connecting to the terminal blocks. The FT3 has two conduit openings to
maintain separation between AC input power and output signal wiring (see Fig. 3.4 on Page 37 for
more information). To eliminate the possibility of noise interference, use a separate conduit for AC
power and cut all wires short for a minimum service loop.

Wiring | 33
Model FT3
Wiring

Wiring Precautions

WARNING! 
• DO NOT OPEN THE ENCLOSURE WHEN ENERGIZED OR AN EXPLOSIVE ATMOSPHERE IS
PRESENT.
• All plumbing and electrical installations of flow meters must be in compliance with local
codes, the end user’s best engineering practices, and manufacturer’s recommendations.
• Connect earth ground to a chassis ground screw on the inside of FT3 enclosure.
• An external power disconnect and 16A over-current protection are required for the AC and
DC powered FT3.
• Do not install the FT3 enclosure near an igniter, igniter-controller or switching equipment.
• Do not install an external power supply in a cabinet containing an igniter controller or
switching equipment.
• This flow meter contains components that can be damaged by static electricity. You must
discharge yourself by touching a grounded steel pipe or other grounded steel material prior
to working inside this flow meter.
• For the remote sensor option, the serial number of the electronics enclosure must match
the remote sensor probe.
• Close any unused conduit openings using suitably certified plugs

Power Wiring
For power wiring, use stranded copper wire, 16 to 20 gauge. If an external 24VDC power source is
used, twisted pair shielded cable is recommended. Supply connection wiring must be rated for at
least 90°C.

Grounding
The enclosure must be properly grounded with a quality earth ground. 16 gauge, stranded wire is
recommended. For US and Canada installation, the internal ground terminal on the enclosure must be
used. Use of the external ground terminal is optional.

Signal Wiring
For signal wiring, the recommended wire gauge is 18 to 22 AWG. Always use twisted pair shielded
cable. The cable shield should not be connected at the flow meter, it should be connected at the
power supply AC ground terminal or instrumentation AC ground. Do not route the power and signal
wires in the same conduit. Power wires must enter left-hand conduit entry. Signal and remote sensor
(where applicable) must enter right-hand conduit entry.

Wiring | 34
 Model FT3
Wiring

Modbus Serial Communication Wiring

A shielded 22 to 18 gauge three conductor cable is recommended for Modbus communication wiring.
Two of the wires in the cable should be twisted pair and used for the communication transmit and
receive signals. The third wire is for the communication common signal. Belden number 310A or a
similar type of cable is recommended, depending on the environment or temperature requirements of
the application.

Remote Sensor Wiring

NOTE! Remote wiring is only required when the Remote Electronics option is provided.

NOTE! Serial Numbers: If you have more than one meter, you must ensure that the serial
numbers of the probe/remote enclosure, electronics enclosure, and flow body match one
another. These items have been manufactured and claibrated to operate as a unit and connot
be mismatched.

For remote sensor wiring, five wire shielded cable is required, the recommended wire gauge is 18
AWG. Use Belden number 5306FE or similar type of cable, depending on environment or temperature
requirements of the application. Make sure that the cable length does not exceed 100 feet and the
wire resistance does not exceed one ohm. Connect the cable shield at the remote enclosure end. Do
not connect the shield at the electronics enclosure.

FT3 Wiring - Conduit Openings

Installation Wiring
Obtain the correct length for the FT3 power and signal wires using one of these methods:
• Trim the wires to extend 2.5 inches out of the enclosure after the conduit and wires are routed to
the FT3 (preferred method).
• Trim the wires to extend 6 inches from the end of the conduit before it is attached to the FT3.

Fig. 3.2: FT3 Wiring - Conduit Openings

Input
Signal Wiring,
Power
Serial Communication
3x 3/4 inch NPT Female Remote Sensor Wiring (option)
F1 F2 F3 F4

Flow Meter Probe

Wiring | 35
Model FT3
Wiring

Power Input Requirements: 24VDC

External DC power supply must provide 24VDC ± 10%, at 0.7 Amps minimum.

The enclosure must be properly grounded with a quality earth ground. Sixteen (16) gauge, stranded
wire, is recommended for power and earth ground.

For US and Canada Zones installations, the internal ground terminal on the enclosure must be used.
Use of the external ground terminal is optional.

Fig. 3.3: Connections for 24VDC Supply

Earth Ground

Red 1
TS2 Earth Ground
Red2
TS3
REMOTE Yel 3
4-20
+1
SENSOR Wh 4
24V Return
FLOW
-2
+3
Wh 5 +24VDC
4-20
#2 1 2 3
-4
TS1
+5
PULSE
/ALM
-6
+7 F1
IN TS4 -2 +1
-8 24V 24V, 0.75A
OUT

J2

CAUTION! Supply connection wiring must be rated for at least 90°C.

Wiring | 36
 Model FT3
Wiring

Power Input Requirements: 100 to 240VAC Supply

If the FT3 has the AC power supply option, the AC power must provide 100 to 240VAC -15% / +10%
(85 to 264VAC) at 0.2 Amps minimum.

The enclosure must be properly grounded with a quality earth ground. Sixteen (16) gauge, stranded
wire, is recommended.

For US and Canada Zones installations, the internal ground terminal on the enclosure must be used.
Use of the external ground terminal is optional.

Fig. 3.4: Connections for optional AC Power

Earth Ground

Red 1
TS2
Red2 Earth Ground
TS3
REMOTE Yel 3
4-20
+1
SENSOR Wh 4
AC (L)
FLOW
-2
+3
Wh 5 AC (N)
4-20
#2 1 2 3
-4
TS1
+5
PULSE
-6
+7 F1
IN TS4 -2 +1
-8 24V 24V, 0.75A
OUT

J2

CAUTION! Supply connection wiring must be rated for at least 90°C.

Wiring | 37
Model FT3
Wiring

4-20mA Output Wiring: Customer-Supplied Power Source

Bring the wiring in through the right hand conduit opening. Connect the 4-20mA flow rate and
4-20mA output #2 temperature or flow rate wiring as shown in the diagram below.

CAUTION! When using the 4-20mA output to control equipment in a failsafe application, see
the wiring configuration on p. 40.

Fig. 3.5: 4-20mA Output Wiring for Customer-Supplied Power Source

FT3 Customer PLC or DCS

Red 1
TS2
Red2 +24VDC
TS3
+1 REMOTE Yel 3
4-20 SENSOR Wh 4 4 to 20mA FLOW RATE
FLOW
-2 Wh 5 * (see important note below)
+3
4-20
#2 -4 1 2 3
24VDC Return
TS1
+5
PULSE
/ALM
-6 +24VDC
+7 F1
IN TS4 +1 -2
-8 24V 4 to 24V,
20mA TEMPERATURE OR
0.75A
OUT FLOW RATE
* (see important note below)
J2
24VDC Return

NOTE!
• When using a 12 volt power supply, the load resistor on the 4-20mA output must be
125 ohms or less to operate properly.
• When using 24 volt power, the load resistor is typically 250 ohms. A 250 ohm resistor in
the 4-20mA circuit will result in a 1 to 5 volt signal to the PLC or DCS.
• When using a 24 volt power supply, the load resistor on the 4-20mA output must be
600 ohms or less.
• Some PLC and DCS equipment have built in load resistors, please refer to the technical
manuals of such equipment.

Wiring | 38
 Model FT3
Wiring

4-20mA Output Wiring: Loop Power Provided by FT3

Bring the 4-20mA wiring in through the right hand conduit opening. Connect the 4-20mA wiring as
shown in the diagram below.

CAUTION! When using the 4-20mA output to control equipment in a failsafe application, see
the wiring configuration on p. 40.

Fig. 3.6: 4-20mA Output Wiring for Loop Power Provided by FT3

FT3 Customer PLC or DCS

TS2 Red 1
Red2
Yel 3
+1 TS3
4-20 REMOTE Wh 4
FLOW
-2 SENSOR + 4 to 20mA FLOW RATE
Wh 5
- * (see important note below)
+3
4-20
#2 + 1 2 3
-4
- * (see important noteTS1
below)
+5
PULSE
/ALM 4 to 20mA TEMPERATURE
-6 OR FLOW RATE
+7 F1
IN (- )2 +1(+)1
TS4 -2
-8
TS424V 24V, 0.75A
OUT
24V
OUT
J1

NOTE!
• This wiring option is only available with the isolated 24V output power option.
• When using a 12 volt power supply, the load resistor on the 4-20mA output must be
125 ohms or less to operate properly.
• When using 24 volt power, the load resistor is typically 250 ohms. A 250 ohm resistor in
the 4-20mA circuit will result in a 1 to 5 volt signal to the PLC or DCS.
• When using a 24 volt power supply, the load resistor on the 4-20mA output must be
600 ohms or less.
• Some PLC and DCS equipment have built in load resistors, please refer to the technical
manuals of such equipment.

Wiring | 39
Model FT3
Wiring

Setting Up the NE-43 Alarms

The FT3 flow meter supports the NAMUR specification NE-43 for alarms on the 4-20mA output. See p.
55 for the 4-20mA ouput NAMUR operation.

CAUTION! Configure the FT3 with the following setup when using the 4-20mA output to
control equipment in a failsafe application.

4-20mA Failsafe Wiring: NAMUR NE-43

When the 4-20mA output is used to control equipment in failsafe applications:
• Wire the 4-20mA output in series with the Alarm output as shown in Fig. 3.7.
• Configure the Pulse/Alarm output to Alarm and select System Alarm as shown in the "Alarm
Output" on Page 58.

The System Alarm output is designed to allow current to flow during normal operation and interrupts
current when power to the meter is lost or in a System Alarm condition.

In the 4-20mA Failsafe Wiring configuration of Fig. 3.7, the 4-20mA signal goes to 0mA if power to
the FT3 is lost or a System Alarm occurs.

Fig. 3.7: 4-20mA Failsafe Wiring and Range of 4-20mA Output for NAMUR Alarm

NAMUR
Range
FT3 Customer PLC or DCS Alarm 21 mA
20 mA
Red 1
Normal Operation
TS2
Red2 +24VDC
Working Range

TS3
+1 REMOTE Yel 3
4-20 SENSOR Wh 4
FLOW
-2 Wh 5
+3
4-20
#2 -4 1 2 3
TS1
+5
PULSE
/ALM
-6
4 to 20mA FLOW RATE 4 mA
+7 F1
IN TS4 +1 -2 3.6 mA
-8 24V 24VDC
24V, Return
0.75A
NAMUR

OUT
Range
Alarm

J2

0 mA

Wiring | 40
 Model FT3
Wiring

Pulse/Alarm Output Wiring

Bring pulse/alarm wiring in through the right-hand conduit opening. Connect to TS2, 5(+) and 6(-).
The pulse/alarm output is an open collector circuit capable of sinking a maximum of 20mA of current.
Pulse or Alarm selection is programmed using the display. Only one option, pulse or alarm, can be
active at a time.

Fig. 3.8: Pulse/Alarm Output Isolated (Recommended)

FT3 Customer PLC or DCS

Red 1
Red2
TS2 TS3
+1 REMOTE Yel 3
4-20 SENSOR Wh 4 +24VDC
FLOW
-2 Wh 5
+3
4-20
#2 1 2 3 2.4K to 10K OHM
-4
TS1
+5
PULSE
/ALM Frequency or Alarm Output
-6
+7 F1
IN TS4 +1 -2
-8 24V 24V, 0.75A
24VDC Return
OUT

J1

NOTE!
• The FT3 Pulse/Alarm output is typically used to drive digital circuitry or solid-
state relays. The output of a solid state relay may, in turn, operate loads such as
electromechanical relays or alarm indicators.
• The maximum load current of the Pulse/Alarm output is 20mA. Choose a load
resistance that provides approximately 10mA with the power supply operating voltage.
• When the output is configured for Alarm and an alarm is not active, the output
will be on (0 volts output). When an alarm is active, the output will be off
(24 volts output).

Wiring | 41
Model FT3
Wiring

Fig. 3.9: Pulse/Alarm Output Local +24V Power Option

FT3 Customer PLC or DCS

Red 1
TS2
Red2
TS3
+1 REMOTE Yel 3
4-20 SENSOR Wh 4
FLOW
-2 Wh 5 2.4K to 10K OHM
+3
4-20
#2 1 2 3
-4
+TS1
+5
PULSE
/ALM Frequency or Alarm Output
-6
+7 (-)2 (+)1 F1
IN TS4 +1 -2 TS4
-8 24V 24V 24V, 0.75A
OUT
OUT

J1

CAUTION!
Do not exceed 42 mA total load on the 24V Output TS4 (ie including 4-20mA outputs).

NOTE!
• This wiring option is only available with the isolated 24V output power option.
• The FT3 Pulse/Alarm output is typically used to drive digital circuitry or solid-
state relays. The output of a solid state relay may, in turn, operate loads such as
electromechanical relays or alarm indicators.
• The maximum load current of the Pulse/Alarm output is 20mA. Choose a load
resistance that provides approximately 10mA with the power supply operating voltage.
• When the output is configured for Alarm and an alarm is not active, the output
will be on (0 volts output). When an alarm is active, the output will be off
(24 volts output).

Wiring | 42
 Model FT3
Wiring

Remote Switch Wiring

A remote switch can be used to reset the Totalizer and elapsed time, if enabled in the programming
settings. There is no polarity requirement on these connections. Use TS2, 7(+) and 8(-).

When the 2 gas curve option is ordered, the switch can be used to switch between curves.

Fig. 3.10: Remote Switch Wiring

FT3 Customer PLC

TS2 or DCS
+1
4-20
FLOW
-2
+3
4-20
#2 1 2 3
-4
TS1
+5
PULSE
/ALM EXTERNAL
-6 SWITCH
+7 F1
IN
-8
24V, 0.75A

J1

Wiring | 43
Model FT3
Wiring

Wiring for Modbus RTU (RS485)

Wiring connections are made to terminal block TS5 for RS485 communication. Terminal block TS5 is
located on the Modbus communication option board of the FT3.

The Tx/Rx+ signal connects to pin 1, Tx/Rx- connects to pin 2 and communication common to pin 3,
and the cable shield to pin 4 as shown in Fig. 3.11.

Termination Resistor
Connect a termination resistor across the receive/transmit signals of the last device on the RS485
communication line. To connect the 121 ohm termination resistor on the FT3, set JP1 to the TERM
position.

Disconnect the termination resistor on all other external RS485 devices. The termination resistor of
the FT3 is disconnected by setting JP1 to the NC (Not Connected) position.

Fig. 3.11: RS485 Wiring

Tx/Rx (+)
Tx/Rx (-)
Communication Common
Cable Shield

Termination Resistor Jumper JP1

Termination Resistor Jumper JP1 (detail)

NOTE!
• JP1 jumper will either be in the NC (Not Connected) or TERM (terminated) position. It
should be in the terminated position on the last meter in the series.

Wiring | 44
 Model FT3
Wiring

HART 4-20mA Output Wiring: Customer-Supplied Power Source

The 4-20mA current loop and HART modem connections are made on the terminal block TS5 pin 1(+)
and pin 2(-). Terminal block TS5 is located on the HART communication option board of the FT3.

Fig. 3.12: HART 4-20mA Output Wiring, Customer-Supplied Power Source

Wiring | 45
Model FT3
Wiring

HART 4-20mA Output Wiring: Loop Power Provided by FT3

The 4-20mA current loop and HART modem connections are made on terminal block TS5 pin 1
(+) and pin 2 (-). Terminal block TS5 is located on the HART communication option board of the
FT3. Isolated 24 volt output power is available on terminal block TS4 pins 1 (+) and 2 (-) of the
HART option board. This output can be used to power the 4-20mA loop if an external supply is not
available..

Fig. 3.13: HART 4-20mA Output Wiring, Loop Power Provided by FT3

Wiring | 46
 Model FT3
Wiring

HART 4-20mA Output Wiring: Handheld Communicator

The 4-20mA current loop and HART modem connections are shown on p. 45 and p. 46.

A handheld HART communicator can be connected to test points TP1 (+) and TP2 (-) with clip leads or
to the 4-20mA terminal block.

Fig. 3.14: HART 4-20mA Output Wiring, Handheld Communicator

Wiring | 47
Model FT3
Wiring

Remote Wiring
Remote wiring is only necessary when the remote sensor option has been ordered.

Fig. 3.15: Remote Wiring

2X 3/4 " NPT, Signal Wiring

Female

Input
Power
F1 F2 F3 F4

Remote Cable, 5 Conductor,

Shielded, 100ft (30.48m) Max.

Five wire shielded cable required. The shielded cable should be run through a separate grounded
steel conduit (no other cables or wires in the conduit). If you are using your own cable, make sure
that the cable length does not exceed 100 feet and has a wire resistance that does not exceed one
ohm (18 AWG recommended).

NOTE! Do not connect the cable shield at the electronics enclosure end. Connect the cable
shield at the remote sensor terminal.

NOTE! The enclosures must be properly grounded with a quality earth ground. 16 gauge,
stranded wire is recommended.

Use an extension cable to connect the terminals of the remote sensor enclosure to connector TS3
located behind the rear cap of the electronics enclosure as shown in Fig. 3.16 and Table 3.1 on the
following page.

NOTE! Serial numbers: If you have more than one meter, you must ensure that the serial
numbers of the probe/remote enclosure, electronics enclosure, and flow body match one
another. These items have been manufactured and calibrated to operate as a unit and cannot
be mismatched.

Wiring | 48
 Model FT3
Wiring

Fig. 3.16: Remote Sensor Wiring

Shield BLK
#4 #2

Cable Shield GRN RED

GRN WHT
#6 WHT WHT #5
RED
RED 1 YEL RED
BLK
TS

RED 2
5

BRN BRN RED

YEL 3 #3 #1
WHT
WHT 4
GRN
WHT 5

TS3
1 2 3
TS1

F1
-2 +1
TS4
24V 24V,0.75A
OUT
Black Dot Denotes Pin #1
J2

Sensor Wires

Electronics Enclosure Probe Sensor Wired By Fox

SENSOR

Remote Enclosure

NOTE! Wire colors listed here represent the wire colors of cables supplied by Fox Thermal.
Colors may vary if customer is supplying their own cable.

Table 3.1: Remote Sensor Cable Wiring

Electronics Enclosure Extension Cable Remote Enclosure Sensor Wire

Terminal Numbers Wire Color Terminal Numbers Color

1 Red 1 Red
2 Black 2 Red
3 Brown 3 Yellow
No Connection Shield 4 Green
4 White 5 White
5 Green 6 White

Wiring | 49
Model FT3
Operation

Start Up Sequence
The program automatically enters the Run/Measure mode after power up. The screen will show the
software version of the FT3 during power up.

USB Interface
The USB interface is a standard feature which allows communication with a PC to monitor readings
and configure settings. FT3 View™, is a free application program from Fox Thermal that connects to
the USB interface and allows data monitoring, configuration setting, data logging to Excel, and an
option to save and recall FT3 configuration data.

FT3 Optional Display and Configuration Panel

The meter can be programmed by using the optional display and configuration panel.

The FT3 display is a 2 line x 16 character display with 4 mechanical buttons and 4 IR (infrared) keys.

The mechanical buttons of the configuration panel can be accessed by removing the FT3 cap. Be sure
to replace the cap after you are done configuring the FT3.

The IR keys and mechanical buttons perform the same function, but the IR keys can be used without
opening the cover. The IR keys can be calibrated for better operation in the field or disabled (p. 89)
when the meter is used in snow or ice in order to avoid false key detection.

Fig. 4.1: FT3 Optional Display and Configuration Panel

Display Window
F1 F2 F3 F4
IR (infrared) Buttons

Push Buttons

Operation | 50
 Model FT3
Operation

Measurement Mode Display Screens

In the measurement mode, there are four different display screens (display 1, 2, 3 and a prompt
screen to enter the programming mode). Two display screens are user programmable (refer to
Display Setup p. 63). Scrolling through the display is accomplished by pressing the F1 or F2 key to
view the next or previous screen.

Pressing the F1 and F2 keys at the same time enters the Log Menu and Engineering Menu screens.

Pressing the F3 and F4 keys at the same time brings up the Reset Total screen prompt.

Fig. 4.2: FT3 Measurement Mode Display Screen Navigation

F1 key: Moves up one screen

F2 key: Moves down one screen
F1

(User programable screen)

Display #1 1456.5 SCFM
123456 SCF

F1 F2 F3 F4 Enter “Reset Total” screen

when F3 & F4 are pressed at
the same time
(User programable screen)
Display #2 Elp = 14.6 HR
88.5˚ F

F1 F2

Display #3 (Fixed screen)

Alarm = None
Elp = 14.6 HR

F1 F2

(Fixed screen)
Display #4 Set Parameter?
No Yes

F2 F4

Enter programming screen

Requires password.
Default is 1234.

Operation | 51
Model FT3
Operation

FT3 Engineering Displays

Pressing the F1 and F2 keys at the same time in the normal mode brings up the engineering displays.
These displays show internal parameters of the FT3 which are used by Fox Thermal service technicians.

Use the F1 and F2 keys to navigate. Press F4 to exit.

There are nineteen (19) screens (10 - 28) to view meter data:
Screen 10 - Flow rate measured by the meter, CSV of the sensor measurement circuit.
Screen 11 - Average CSV of the sensor measurement circuit, velocity flow in user-selected unit.
Screen 12 - Sensor filtered average voltage, velocity in meter/hour.
Screen 13 - TSI average count, TSV average count.
Screen 14 - TSI in volts, TSV in volts.
Screen 15 - TSI current in Amp, TSI resistance in ohm.
Screen 16 - RTD9 count, gas temperature in degrees C.
Screen 17 - Channel 1 4-20mA current loop count, channel 2 4-20mA current loop count.
Screen 18 - Frequency output count, active alarm codes.
Screen 19 - High and low flow alarm settings.
Screen 20 - High and low temperature alarm settings.
Screen 21 - Elapsed time of meter operation and the status in hexadecimal.
Screen 22 - FT3 electronics firmware version, optional display firmware version.
Screen 23 - Total number of power cycles, number of errors in total flow measurement.
Screen 24 - TSI resistance in ohm, RTD9 resistance in Ohm.
Screen 25 - Most recent CAL-V™ value, CAL-V™ last verify value.
Screen 26 - Bridge shutdown detection count.
Screen 27 - Zero CAL-CHECK™ pipe reference value, most recent Zero CAL-CHECK™ test difference.
Screen 28 - Zero CAL-CHECK™ bottle reference value, most recent Zero CAL-CHECK™ test difference.

Operation | 52
 Model FT3
Operation

Programming: Data Entry using the Display and Configuration Panel

There are 2 basic types of menu entries: one for changing value or string and one for selecting from a
selection list.

To Change a Value or String

VALUE = 0.91234
CHG OK

F1 F2 F3 F4

Press CHG (F1) key to change the value, OK (F4) to accept the value.

VALUE = 0.91234
UP DN NXT OK

F1 F2 F3 F4

Press the UP (F1) or DN (F2) key to select a new digit or character, the cursor points to the selected
digit. Press NXT (F3) to select the next digit and OK (F4) to accept the entry.

To Select from a List

FLO UNT = SCFM

NXT OK

F1 F2 F3 F4

Press NXT (F1) key repeatedly until the correct selection is made and OK (F4) key to accept the entry.

Entering the Programming Mode

To enter the programming mode and access the SET PARAMETERS menu, press the F1 or F2 key in
the normal running mode until the following screen is shown:

SET PARAMETERS ?
No Yes

F1 F2 F3 F4

Press YES (F4) and the following screen will prompt user to enter password:

PASWD:_
UP DN NXT OK

F1 F2 F3 F4

Enter the correct password, then follow the instructions for changing a value as specified above. The
default Level 1 password is “1234”.

Operation | 53
Model FT3
Operation

If the wrong password is entered, the message “Wrong Password” will display and then return to the
programming entry screen.

SET PARAMETERS Menu (Main Menu)

If the password is accepted, the SET PARAMETERS menu will be shown:

SET PARAMETERS
I/O FLO DSP EXIT

F1 F2 F3 F4

This is the screen for the programming mode. Press EXIT (F4) repeatedly until “Normal Mode” is
seen briefly to exit the programming mode.

Analog 4-20mA Outputs

The following menu allows the scaling of the analog 4-20mA output. From the SET PARAMETERS
menu, press I/O (F1) to move to the 4-20mA output selection.

SET I/O
COM I/O 420 EXIT

F1 F2 F3 F4

In this screen press 420 (F3) (screen appearance may vary according to options).

SET 4-20 mA
CH1 CH2 EXIT

F1 F2 F3 F4

Select CH1 (F1) to program channel 1.

20 mA = 3500 SCFM
CHG OK

F1 F2 F3 F4

Enter the value for the 20mA and press OK (F4) key to accept the setting.

NOTE! When the flow rate exceeds the programmed value for the 20mA set point, the analog
output will stay at 20mA and an alarm code will be generated.

Operation | 54
 Model FT3
Operation

Then the following screen will display:

4 mA = 0 SCFM
CHG OK

F1 F2 F3 F4

Enter the value for the 4mA and press OK (F4).

NOTE! 4mA is normally set to 0.

The following menu item allows the user to select an alarm level on the 4-20mA output when a
serious issue is detected that is preventing the calculation of a correct flow value
The options are:
• mA Fault=3.6 mA (Force the 4-20mA signal to 3.6mA on alarm)
• mA Fault=21 mA (Force the 4-20mA signal to 21mA on alarm)
• mA Fault=Not use (4-20mA signal alarm fault not used)

CAUTION! When using the 4-20mA output to control equipment in a failsafe application, use
the wiring configuration and set the Pulse/Alarm Output to System alarm as shown in "Alarm
Output" on p. 58.

After setting the 4mA output value, choose the mA fault value:

mA Fault = Not use

NXT OK

F1 F2 F3 F4

The following events will set the output to 3.6mA or 21mA if the alarm level is selected:
• Sensor resistance above high limit
• Bridge Shutdown

When the 4-20mA output is wired through the System Alarm, the following cause the output to go to
0mA:
• Power to the Microprocessor is lost
• Sensor or electronics failure

Fig. 4.3: Range of 4-20mA Output and NAMUR Alarm

NAMUR Working Range NAMUR

Alarm Alarm
Range Normal Operation Range

Operation | 55
Model FT3
Operation

To exit the programming mode, press (F4) repeatedly until Normal Mode is seen.

Select CH2 (F2) to program channel 2. Channel 2 is programmable for flow (CH2=Flow) or
temperature (CH2=Temp).

CH2 = Temp
NXT OK

F1 F2 F3 F4

Press NXT (F1) to select Flow or Temperature and then press OK (F4).

20 mA = 300 º F
CHG OK

F1 F2 F3 F4

Enter the value for the 20mA and press OK (F4) key to accept the setting.

Then the following screen will display:

4 mA = 10 º F
CHG OK

F1 F2 F3 F4

Enter the value for the 4mA and press OK (F4).

Press (F4) repeatedly until “Normal Mode” is seen briefly to exit the programming mode.

Pulse/Alarm Output
From the SET PARAMETERS menu, press I/O (F1), then I/O (F2).

SET I/O
INP OUT EXIT

F1 F2 F3 F4

Press OUT (F2) to select output. The following screen will show:

OUT = Frequency
NXT OK

F1 F2 F3 F4

Press NEXT (F1) to cycle through output options until you have the selection for "OUT=Frequency"
and press OK (F4).

Operation | 56
 Model FT3
Operation

The frequency output can be configured in once of three ways:

1. Specifying how many pulses per unit, P/U (i.e., 10 pulses per SCF)
2. Specifying how many flow units total per pulse, U/P (i.e., 0.1 SCF per pulse)
3. Specifying a maximum frequency to a defined maximum value of flow rate

All of these approaches are equivalent.

FREQUENCY OUTPUT
P/U U/P FEQ EXIT

F1 F2 F3 F4

Use P/U (F1) to enter pulse per unit, U/P (F2) for unit per pulse or FEQ (F3) to enter the flow and
maximum frequency to scale the frequency output.

NOTE! When data is entered with any of the three described methods, the other values will
be re-calculated according to the settings.

Entering data in Pulse per Unit

Press P/U (F1) and the following screen will show:

PLS/UNT = 2
CHG OK

F1 F2 F3 F4

Press CHG (F1) to change the setting and then OK (F4) to accept entry. The value entered is in pulse
per selected flow unit total (for example, 2 pulses per SCF).

Entering data in Unit per Pulse

Press U/P (F2) and the following screen will show:

UNT/PLS = 0.5
CHG OK

F1 F2 F3 F4

Press CHG (F1) to change the setting and then OK (F4) to accept entry.
The value entered is in unit per pulse (for example. 0.5 flow unit total per pulse)

Entering data with flow and maximum frequency

Press FEQ (F3) and the following screen will show:

Operation | 57
Model FT3
Operation

MaxFreq=100 Hz
CHG OK

F1 F2 F3 F4

Enter the maximum pulse rate (frequency) and press OK (F4).

CAUTION! Maximum pulse rate (frequency) cannot exceed 100 Hz.

The next screen will show:

MaxFlo=5000 SCFM
CHG OK

F1 F2 F3 F4

NOTE! If the flow rate exceeds the maximum pulse rate (frequency), the output will stay at
100 Hz and the FT3 will issue an alarm code.
Alarm Output
To program the Alarm output, press I/O (F1) key from the SET PARAMETERS menu. Then select I/O
(F2) and the screen will show:

SET I/O
INP OUT EXIT

F1 F2 F3 F4

Then press OUT (F2) and the screen may show:

OUT = HiFloAlm
NXT OK

F1 F2 F3 F4

Then press NXT (F1) to select the correct alarm and press OK (F4).
Selections are:
Not used
Frequency
HiFloAlm = High Flow Alarm
LoFloAlm = Low Flow Alarm
HiTempAlm = High Temperature Alarm
LoTempAlm = Low Temperature Alarm
System Alm = System Alarm

Operation | 58
 Model FT3
Operation

When the output is set to Alarm and there is no alarm condition, the output will be on (0 volts). When
an alarm is active, the output is turned off (24 volts).

HiFloAlm=500 SCFM
CHG OK

F1 F2 F3 F4

Enter the value for the limit by pressing CHG (F1) and then OK (F4). A value of 0 disables the alarm.

NOTE! There is only one output to operate as a pulse output or an alarm output. Both
cannot operate at the same time.

Contact Input Settings

From the SET PARAMETERS menu, press I/O (F1) and then I/O (F2) and then INP (F1) key to select
input. The following menu will display:

INP=Not Used
NXT OK

F1 F2 F3 F4

Press NXT (F1) until the correct selection is shown and then press OK (F4) to accept the setting.
Selections are:
Not used
Tot Reset = Reset the totalizer
Switch Crv = Switch between calibration curve 1 and curve 2 (only if 2 gas curve ordered)

Press EXIT (F4) repeatedly until you exit programming mode.

FT3 with 2 Gas Curves

This section describes added features to the standard FT3 flow meter when using the 2 gas curves
firmware option. The 2 Gas Curves firmware allows the use of two different calibration tables when
running with different gases. One of two methods can be used to switch between the two calibration
curves:

1) Use of Contact Input:

When the contact input is programmed for curve switching, an open contact will select curve #1 and a
contact closure will select curve #2.

2) Use of the Keypad:

If the contact input is not programmed for curve switching, pressing F2 and F3 simultaneously will
prompt an operator to manually switch curve upon entering a password and confirming the action by
pressing the appropriate key.

Operation | 59
Model FT3
Operation

Pressing F2 and F3 simultaneously:

SWITCH TO CRV 1?
NO YES

F1 F2 F3 F4

Password needs to be entered if active (default: 1234):

PASSWORD:_
UP DN NXT OK

F1 F2 F3 F4

After entering a valid password, a brief confirmation message will be displayed for 1 second:

SWITCH TO CRV 1

F1 F2 F3 F4

Programming Contact Input for Curve Switching

Enter the menu using steps outlined in "Contact Input Settings" section (p. 59) and select "Switch
CRV". Please note that the flow meter needs to be programmed for 2 gas curves at the Fox factory
before you can select this function. Flow meters are shipped with pre-programmed user requested
settings.

INP=SWITCH CRV
NXT OK

F1 F2 F3 F4

Selections are: "Not used"

"Tot Reset"
"Switch Crv"

NOTE! Helpful hint: From normal display mode, press F4 to view the current gas curve
selection.

Operation of the 2 Gas Curves

To avoid confusion, only one of two techniques is enabled. If the contact input is assigned to switch
gas curves, then the ability to switch using the F2 and F3 function keys on the front panel is disabled.

Operation | 60
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Operation

Two totalizers (Total 1 and Total 2) and two elapsed time counters are available on the display and
through the USB serial communication. The reset function will reset all totalizers and elapsed time
counter to zero.

In the event of a power failure, the software will remember the last curve in use. Upon powering up
again, the FT3 unit will continue to use that curve.

Switching between gas curves will require a password unless the password is set to "0", which disables
it. The calibration certificates for order with 2 gas curves will identify which gas is Gas 1 and Gas 2.
When measuring in mass units, a density value must be entered for each gas curve.

Programming Densities for Curve 1 and Curve 2

When the selected flow unit is mass/time, two different densities will be used for each curve if the
meter has been programmed for 2 gas curves. To change the densities:

Go to the unit menu following "Unit Settings" section.

DNS1 = 0.9876
CHG OK

F1 F2 F3 F4

DNS1 is the density associated with curve 1. Change it as needed and press OK (F4).

DNS2 = 1.2876
CHG OK

F1 F2 F3 F4

DNS2 is the density associated with curve 1. Change it as needed and press OK (F4).

Programming 4-20mA settings for Curve 1 and Curve 2

When the meter has been programmed for 2 gas curves, 2 sets of 4-20mA settings for flow rate are
used. To program these settings:

Go to the 4-20mA setting following the "Analog 4-20mA Settings" section.

20mA = 500SCFM
CHG OK

F1 F2 F3 F4

20mA is the upper limit associated with curve 1. Change it as needed and press OK (F4).

Operation | 61
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4mA = 0
CHG OK

F1 F2 F3 F4

4mA is the lower limit associated with curve 1. Change it as needed and press OK (F4).

20 maCv2=450 SCFM
CHG OK

F1 F2 F3 F4

20 maCv2 is the upper limit associated with curve 2. Change it as needed and press OK (F4).

4 maCv2=0
CHG OK

F1 F2 F3 F4

4 maCv2 is the lower limit associated with curve 2. Change it as needed and press OK (F4).

Serial Communication Settings

The Serial communication settings can be programmed by pressing I/O (F1) key from the SET
PARAMETERS menu. The screen will show:

SET I/O
COM I/O 420 EXIT

F1 F2 F3 F4

Press COM (F1) to select Serial communication.

The screen may show:

Comm=Modbus
NXT OK

F1 F2 F3 F4

Options for serial communication are:

Not Used
Modbus
HART

NOTE! Any selection other than “Not Used” requires the communication option for the
selected communication type. If enabling a communication option, see the associated
Communication section of this manual for specific programming information.

Operation | 62
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Display Setup
There are four display screens that you can cycle through in normal operating mode (see Fig. 4.2 on
p. 51). Two of the four display screens are fixed and cannot be changed (Display 3 and Display 4).
The other two screens are programmable to show the information that you prefer.

Display #1 Display #2
DSP1L1 DSP2L1
DSP1L2 DSP2L2

F1 F2 F3 F4 F1 F2 F3 F4

Selections are:
DSP1L1 = Display 1, Line 1
DSP1L2 = Display 1, Line 2
DSP2L1 = Display 2, Line 1
DSP2L2 = Display 2, Line 2

To Program Display Screens #1 and 2

From the SET PARAMETERS menu press DSP (F3) to select the DISPLAY menu:

DISPLAY/PASSWORD
DSP IR PSW EXIT

F1 F2 F3 F4

Press DSP (F1) key. The display will show:

DSP1L1 = Flo rate

NXT OK

F1 F2 F3 F4

These are the selections for the Display 1, Line 1.

Selections are:
Flo rate = Flow rate
Total = Total mass or volume
Elps = Elapsed time
Temp = Temperature
Alarm = Error codes
When the selection is correct, press OK (F4) to accept. The display will then go through the same
process for all 4 lines of the 2 programmable displays (DSP1L1, DSP1L2, DSP2L1 and DSP2L2).
After the last line of Display 2 is accepted, the display will show the following menu:

ALTERNATE = Off
NXT OK

F1 F2 F3 F4

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Model FT3
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This menu allows you to alternate between menu display 1 and 2 every few seconds.
Selections are: On or Off

Press OK (F4) to accept selection. Press EXIT (F4) repeatedly until “Normal Mode” is seen briefly to
exit the programming mode.

Password
There are two user level passwords, only Level 1 is programmable and gives access to all the normal
settings. The second password is used to allow access to calibration settings.

Default Level 1 password is “1234”, and Level 2 password is “9111”. The Level 1 programmable
password can be disabled by setting it to “0”.

From the SET PARAMETERS menu press DSP (F3) to select the DISPLAY menu.

To Program the Password

DISPLAY/PASSWORD
DSP IR PSW EXIT

F1 F2 F3 F4

Press PSW (F3) key to select password.

PASSWD = 1234
CHG OK

F1 F2 F3 F4

This screen displays the current Level 1 password.

Press CHG (F1) key to change the password and enter new value.

Press OK (F4) to accept new data and exit programming by pressing EXIT (F4) key repeatedly until
out of the programming mode.

NOTE! Password can be number or letter characters up to 4 digits.

Units Settings
This menu is used to set the units for mass flow, temperature, and pressure as well as the setting
of reference temperature and reference pressure. These values will be set at Fox Thermal using
information supplied by the customer. These values can be changed to match a new application. The
units setting is accessed from the SET PARAMETERS menu. To access the Unit Settings Menu:

Operation | 64
 Model FT3
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SET PARAMETERS
I/O FLO DSP EXIT

F1 F2 F3 F4

Press FLO (F2):

FLOW PARAMETERS 1
DGN UNT PRM EXIT

F1 F2 F3 F4

Press UNT (F2) for Unit selection.

The screen will show:

FLO = SCFM
NXT OK

F1 F2 F3 F4

Press NXT (F1) to change selection and OK (F4) to accept.

Flow Units
Selections for flow units are:
SCFM KG/M LBS/D SM3/H MSCFD (MCFD)
SCFH KG/S NLPH SM3/D MMSCFD (MMCFD)
NM3/H LBS/H NLPM NM3/D MCFD (MSCFD)
NM3/M LBS/M NLPS SLPM MMSCFM (MMCFM)
KG/H LBS/S SM3/M SCFD MT/H
SMPS NMPS SFPM

NOTE! The totalizer must be reset immediately after changing the flow units setting.

NOTE! The totalizer (total flow measured) will roll over when reaching a certain value. The
maximum value is dependent on the flow units selected (see Totalizer Rollover p. 74).

WARNING! The FT3 re-calculates area, 4 and 20mA values, maximum flow for the pulse
output and zero flow cutoff when changing flow units except for velocity units. When going
to or from velocity units, the FT3 will not recalculate these values and these values must be
re-entered manually.

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Temperature Units
After pressing OK (F4) to accept the Flow unit the display will prompt for the temperature unit
setting:

TMP UNT= Deg F

NXT OK

F1 F2 F3 F4

Press NXT (F1) to change selection and OK (F4) to accept.

Selections for Temperature units are: Deg C or Deg F

Reference Temperature
After pressing OK (F4) to accept the temperature unit setting, the display will prompt for temperature
reference in selected unit.

TmpRef = 60 °F
CHG OK

F1 F2 F3 F4

Press CHG (F1) to change the reference and OK (F4) to accept.

Pressure Units
After pressing OK (F4) to accept the reference temperature, the display will prompt for the reference
pressure unit selection:

PRES UNT= Psia

NXT OK

F1 F2 F3 F4

Press NXT (F1) to select next entry and OK (F4) to accept.

Selections are:
mmHG = Millimeters of mercury (absolute)
Psia = Pounds per square inch absolute
bara = Bar absolute

Reference Pressure
After the pressure unit selection is made, the display will show a menu to enter the reference pressure:

PresRef= 14.7
CHG OK

F1 F2 F3 F4

Press CHG (F1) to change it and OK (F4) to accept.

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Accessing Flow Parameters and Alarm Settings

The FLOW PARAMETER 1 menu is used to set various flow parameter values. They are: Flow cutoff,
pipe diameter, filter, high and low alarm for flow and temperature.

NOTE! The parameters in this menu are set to the customer specifications at the factory. They
should only be changed when changing the application of the flow meter.

SET PARAMETERS
I/O FLO DSP EXIT

F1 F2 F3 F4

The FLOW PARAMETER 1 menu is accessed from the SET PARAMETERS menu by pressing FLO (F2):

FLOW PARAMETER 1
DGN UNT PRM EXIT

F1 F2 F3 F4

Then press PRM (F3):

FLOW PARAMETER 2
CAL SPC PRM EXIT

F1 F2 F3 F4

NOTE! The CAL and SPC function key will only appear and be accessible from a Level 2
password.

Then press PRM (F3). This will move into settings for flow cutoff, pipe diameter, and filter value.
These settings will be followed by the high and low alarm settings for flow rate and/or temperature.

Programming Flow Parameters

Flow Cutoff
The first parameter is Flow Cutoff:

CUTOFF = 2.0 SCFM

CHG OK

F1 F2 F3 F4

Enter the value for the flow cutoff and then press OK (F4). When the flow rate falls below the flow
cutoff, the flow meter will display a flow value of zero.

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Model FT3
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Pipe Area
Enter the pipe area in square meters or square feet and then press OK (F4). Use square meter for
metric flow unit selection.

A^2 = 0.05672 Ft^2

CHG OK

F1 F2 F3 F4

Filter Value
The filter value is entered in seconds. The allowable time constant range is 0.8 to 10 seconds. The
filter time interval is proportional to the dampening.

The filter value is also referred to as a dampening factor and is used to quiet the readings. The filter
value is an exponential filter that dampens the noise and is used as follows:
Flow Value = (FA * new value) + (FB * average)
Where FA = filter value, FA + FB is equal to 1.0

A lower filter value will increase dampening of the flow rate and smooth the reading. A lower filter
value will also slow the meter's response. For example, if we enter a filter of 0.8, the weight ratio for
the new average is:
New average = (80% new sample) + (20% last average)
Filter range is 0.01 to 1.0, 0.01 being a high filter value and 1.0 = no filter.

Filter Response (Sec.) 65% of Target

0.9 0.10
0.8 0.15
0.7 0.20
0.6 0.25
0.5 0.30
0.4 0.35
0.3 0.40
0.2 0.60
0.1 1.00
0.05 2.00
0.03 3.00
0.01 10.3

FILTER = 0.8 sec

CHG OK

F1 F2 F3 F4

Enter the filter value and then press OK (F4).

Operation | 68
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Programming High and Low Alarm Settings

Settings for the alarms directly follow the flow parameters for flow cutoff, pipe diameter, and filter
value. These alarms can be used without the digital output assigned to the alarm. If that is the case,
the alarm status will only be shown on the display, through serial communication, or FT3 View™. If the
digital output is assigned to an alarm, changing the value here will change that setting.

High Flow Rate Alarm

This is the upper flow limit alarm value that can be associated with the alarm output. An alarm code is
generated when the flow value exceeds this limit. If no alarm is needed, set this value to zero.

To set the parameters for a high flow rate alarm, press CHG (F1):

HiFloAlm = 1234 SCFM

CHG OK

F1 F2 F3 F4

Press OK (F4) to accept the value.

Low Flow Rate Alarm

This is the lower flow limit alarm value that can be associated with the alarm output. An alarm code is
generated when the flow value is below this limit. If no alarm is needed, set this value to zero.

To set the parameters for a low flow rate alarm, press CHG (F1):

LoFloAlm = 100 SCFM

CHG OK

F1 F2 F3 F4

Press OK (F4) to accept the value.

High Temperature Alarm

This is the upper temperature limit alarm value that can be associated with the alarm output. An
alarm code is generated when the temperature value exceeds this limit. If no alarm is needed, set this
value to zero.

To set the parameters for a high temperature alarm, press CHG (F1):

HiTmpAlm = 200 F
CHG OK

F1 F2 F3 F4

Press OK (F4) to accept the value.

Operation | 69
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Low Temperature Alarm

This is the lower temperature limit alarm value that can be associated with the alarm output. An
alarm code is generated when the temperature value is below this limit. If no alarm is needed, set this
value to zero.

To set the parameters for a high temperature alarm, press CHG (F1):

LoTmpAlm = 20 F
CHG OK

F1 F2 F3 F4

Press OK (F4) to accept the value.

Simulation
This menu allows for simulation of flow rate and temperature. It should only be used for testing
and demonstration purposes. Make sure to return all of these simulation values to zero, before
returning to the normal mode of operation.

CAUTION! If the 4-20mA and/or the pulse/alarm outputs are connected to controllers, set
the controllers to “manual” to ensure that the simulated signals do not cause false controller
action.

The DIAGNOSTIC menu used for Simulation is accessible from the SET PARAMETERS menu by
pressing FLO (F2):

FLOW PARAMETER 1
DGN UNT PRM EXIT

F1 F2 F3 F4

Pressing DGN (F1) will show:

DIAGNOSTIC
SIM TST EXIT

F1 F2 F3 F4

Pressing SIM (F1) will show:

SIMULATE FLOW?
YES NO

F1 F2 F3 F4

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 Model FT3
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Pressing YES (F1) will show:

FloSim = 0 SCFM
CHG OK

F1 F2 F3 F4

Enter the value and then press OK (F4).

NOTE! Enter zero to disable this feature.

The screen will show:

SIMULATE TEMP?
YES NO

F1 F2 F3 F4

Pressing YES (F1) will show:

TmpSim = 0 C
CHG OK

F1 F2 F3 F4

Enter the value and then press OK (F4).

NOTE! Enter zero to disable this feature.

The screen will show:

SIMULATE CSV?
YES NO

F1 F2 F3 F4

Pressing YES (F1) will show:

CsvSim = 0 V
CHG OK

F1 F2 F3 F4

Enter the value and then press OK (F4).

NOTE! This value is used to simulate the Current Sense Voltage (CSV) and should be set to
zero for normal mode.
Operation | 71
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ENABLE SIM?
YES NO

F1 F2 F3 F4

Press YES (F1) to start the simulation mode, otherwise press NO (F4). Upon pressing either key, the
program will return to the FLOW PARAMETER 1 screen.

NOTE! Simulation Mode will be cleared if the power is cycled.

Calibration Parameters
This menu allows changing the factory calibrated setting of the flow meter and is accessible with a
Level 2 password. Calibration parameter values are set for temperature and pressure at 0 degree C
and 760 mmHg. These settings should normally never be changed except by Fox Thermal personnel
at the factory.

This calibration menu is entered from the SET PARAMETERS menu by pressing FLO, PRM, and CAL.

FLOW PARAMETER 2
CAL SPC PRM EXIT

F1 F2 F3 F4

Press CAL (F1) then the display will show:

CAL TABLE
TB1 --- --- EXIT

F1 F2 F3 F4

Press TB1 (F1) then the display will show:

Volt1 = 0.92367
CHG PRV NXT EXIT

F1 F2 F3 F4

Press NXT (F3) then the display will show:

Flo1 = 0
CHG PRV NXT EXIT

F1 F2 F3 F4

Use the CHG (F1) key to change the entry, PRV (F2) to move to the previous entry, NXT (F3) to move
to the next entry and EXIT (F4) to return.

Operation | 72
 Model FT3
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Pressing the NXT (F3) key will show the data point voltage and then mass velocity and then go to the
next data point. The number after Volt (i.e., Volt1) or Flo (i.e., Flo1) indicated the data point number.

The calibration table can hold up to 20 data pair points. Each data point has a voltage and mass
velocity associated with it.

K Factor
The K Factor allows the user to adjust the meter’s calibration. The flow meter increases the calculated
flow rate by the K Factor. This results in a direct scaling of the meter’s output across the entire full
range.

The K Factor parameter is accessed from the FLOW PARAMETER 2 menu by entering a Level 2
password “9111” and pressing the SPC key (F2).

FLOW PARAMETER 2
CAL SPC PRM EXIT

F1 F2 F3 F4

The following screen will be displayed:

K fact=0%
CHG OK

F1 F2 F3 F4

Press CHG (F1). Add the correction factor and press OK (F4).

If you want the flow meter to read 5% higher, enter 5.0%.

If you want the flow meter to read 5% lower, enter -5.0%.
If an existing K Factor is present, add the additional K Factor to the existing value.

Upon pressing OK (F4), an option to restore the database will follow.

Restore Database
In case of user error, the ability to restore the meter to the original factory settings can be achieved in
this menu. The display will show:

RESTORE DATABASE?
YES NO

F1 F2 F3 F4

Press YES (F1) ONLY if you want to restore your database to the initial factory setting that the meter
was shipped with. All current user-entered settings will be overwritten. The green LP3 LED will flash at
a faster pace until the recall is performed. The "RESET CRC" screen will follow "RESTORE DATABASE".
Upon pressing NO (F4), an option to reset the NVRAM CRC will follow.

Operation | 73
Model FT3
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Reset CRC
If the NVRAM CRC check fails (Error Code 36), the programmed settings values will need to be verified
and corrected before clearing the error. Call Fox Thermal Customer Service if you need assistance.

RESET CRC?
YES NO

F1 F2 F3 F4

Press YES (F1) ONLY if you want to reset the CRC and generate a new CRC value.

Reset Total and Elapsed Time

Enter the flow totalizer and elapsed time screen by pressing the F3 and F4 keys at the same time in
the normal running mode.

RESET TOTAL ?
NO YES

F1 F2 F3 F4

Press YES (F4) and enter password to reset total and elapsed time. Press NO (F1) to cancel.

NOTE! This feature is not available on non-resettable units.

Totalizer Rollover: The FT3 has an automatic roll-over function. The total flow count of the FT3 will
roll over after 99,999,999,999. Except for:
MSCFD: 999,999,999
MMSCFM: 9,999,999
MMSCFD: 999,999

Calibration of the Fox Thermal Model FT3 Thermal Flow Meter

To ensure that all Fox Thermal flow meters meet specified performance parameters and
provide accurate, repeatable measurements in the field, all calibrations are performed with
NIST-traceable flow standards. Each meter is shipped from the factory with a Fox Thermal
Calibration Certificate.

Calibration Validation
Operators can verify the meter is running accurately in the field by performing two simple tests.

The first test, CAL-V™, tests the functionality of the sensor and its associated signal processing
circuitry and can be done in the pipe and in normal processing conditions.

The second test, Zero CAL-CHECK™, ensures the repeatability and cleanliness of the sensor and can be
performed in two ways: In situ or Out of Pipe. See Fig. 4.4 to understand Calibration Validation with
these two tests.

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 Model FT3
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Fig. 4.4: Total Calibration Validation

CALIBRATION VALIDATION ON FOX MODEL FT3

CAL-V™ Zero CAL-CHECK™
Sensor and Electronics Test Sensor Test at Zero Flow vs. Sensor Test at Zero Flow vs.
Field Baseline Factory Baseline
IN SITU IN SITU OUT OF PIPE
• Complete test of sensor elements • Customer-set zero flow baseline • Test compares sensor
and electronics established under normal zero characteristics at zero flow at
• In the pipe, under normal process flow conditions ambient temperature and
conditions • Test compares sensor atmospheric pressure with
• Operator-initiated via front panel, characteristics at zero flow with factory characteristics
FT3 View™, or MODBUS customer-set zero flow baseline • Used when in situ zero flow
• Hold outputs at last value or go • Operator-initiated via front panel, condition cannot be established
to zero; operator-selectable FT3 View™, or MODBUS • Operator-initiated via front panel,
• Test takes less than 5 minutes • Use of packing gland assembly to FT3 View™, or MODBUS
• Test results in pass/fail message retract probe is a convenient way • Test takes less than 5 minutes
• Data saved in meter for look-up to establish a zero flow condition after out of pipe set-up complete
anytime • Test takes less than 5 minutes • Calibration Validation Certificate
• Calibration Validation Certificate after zero flow condition can be generated if test is
can be generated if test is established initiated using FT3 View™
initiated using FT3 View™ • Calibration Validation Certificate software
software can be generated if test is
initiated using FT3™ View
software

Fox Thermal has developed Calibration Validation, using the CAL-V™ and Zero CAL-CHECK™ tests to
help our customers avoid sending the meter back for annual or biennial re-calibrations.

CAL-V - Calibration Validation Test 1

CAL-V™ ensures the repeatability, functionality of the sensor and its associated signal
processing circuitry, and cleanliness of the sensor.

During the CAL-V™ calibration validation test, the microprocessor adjusts current to the
sensor elements and determines the resulting electrical characteristics. Data within established
tolerances confirms the meter is accurate.

NOTE! If the CAL-V™ test is performed using the Fox Thermal FT3 View™ Software, at the
completion of the test, a CAL-V™ Certificate may be printed for a record of the test. This
certificate will display a pass/fail result.

Operation | 75
Model FT3
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Performing the CAL-V™ Calibration Validation Test

Press FLO (F2) from the SET PARAMETERS menu. The display will show:

FLOW PARAMETER 1
DGN UNT PRM EXIT

F1 F2 F3 F4

Press DGN (F1). The display will show:

DIAGNOSTIC
SIM TST EXIT

F1 F2 F3 F4

Press TST (F2). The display will show:

DIAGNOSTIC
CALV ZRO EXIT

F1 F2 F3 F4

Press CALV (F1). The display will show:

CAL-V
VER EXIT

F1 F2 F3 F4

Press VER (F1) to get to the go to zero screen. The display will show:

Flo: Go to Zero
NXT EXIT OK

F1 F2 F3 F4

To select what the flow output will do during a CAL-V™, choose from these options:
• Go to Zero: Flow output will be zero during the test (i.e. 4mA)
• Hold Value: Flow will hold last value during the test

Select the option and press OK (F4).

NOTE! The FT3 will stop measuring flow when performing this test.

Take Control
off-line EXIT OK

F1 F2 F3 F4

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 Model FT3
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WARNING! If you are using closed loop control, the system needs to be taken off-line during
the test.

Press OK (F4) to start CAL-V™. The screen will show:

Verifying CAL-V Verifying CAL-V

Cal = 12.7 T=123 Please Wait

F1 F2 F3 F4 F1 F2 F3 F4

This test will take up to 4 minutes (less time if there is flow) and will show the Cal value changing as
the power to the sensor is adjusted. The T=xxx is a count down timer indicating how much time is left
to finish the test. A “Please Wait” message will be flashing on and off on line 2 during this test.

CAL-V™ Test Results

Upon test completion, the final CAL-V™ value will be displayed along with a Pass or Fail message:
• Pass: less than ±2.5
• Fail: equal to or greater than ±2.5

Recommended next steps if a "Fail" result is displayed:

• Run the test again under a higher flow rate if possible.
• Remove the probe from the pipe, clean the sensor, and perform the test again under a normal
or high flow rate.

If a "Fail" result is displayed after repeating the test, please call Fox Thermal Service at (831) 384-4300
for assistance.

CAL-V = 0.251
Pass OK

F1 F2 F3 F4

Press OK (F4) to exit the menu when the test is complete.

CAUTION!
• The CAL-V™ test is valid for checking the calibration accuracy of flow meters installed in the
applications for which it was calibrated including the gas/gas mixture, calibration range, and
pipe size shown on the calibration certificate.
• For applications with temperature exceeding 250°F (121°C), CAL-V™ test results may vary.
• Periodic inspection for damage and cleaning of the sensor elements is required.

Zero CAL-CHECK™ - Calibration Validation Test 2

The Zero CAL-CHECK™ test is a companion test to CAL-V™. Unlike CAL-V™, which may be performed
in the pipe and at process conditions, Zero CAL-CHECK™ must be performed at zero flow to ensure a
valid test result. This test is used to confirm that the flow meter still retains its original NIST-traceable
calibration at zero flow and that the sensor is free of film or residue that may affect readings. The test

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takes less than 5 minutes to complete. At the conclusion of the test, a Pass or Fail message will be
displayed. Press F4 at the conclusion of the test to return to normal measuring mode or to terminate
the test.

There are a few ways that Zero CAL-CHECK™ is different than CAL-V™:
• The Zero CAL-CHECK™ test must be performed at a "no flow" condition (ie zero flow)
• If the Zero CAL-CHECK™ test is to be performed in the pipe, the field baseline must be set before
an actual test can be performed (see "Setting Field Baseline for In Situ Zero CAL-CHECK™ Tests" on
p. 79).
• If the Zero CAL-CHECK™ test is to be performed out of the pipe, the meter must be set upside-
down (probe pointing up) and the PVC sensor protector that the meter was shipped with must be
placed back over the sensor to achieve the factory baseline that the meter has been set with.

Techniques for Achieving Zero Flow - In the Pipe

In situ (in the pipe) Zero CAL-CHECK™ testing can be achieved in one of two common ways:
• Fox Thermal Retractor
• The first in situ option is achieved through the use of a Fox Thermal retractor that may be
ordered as an option for most inline- or insertion- type meters. The assembly allows the
operator to retract and isolate the sensor from the process in order to conduct the Zero CAL-
CHECK™ test. This is particularly beneficial for applications in which the process is not easily
stopped.
• Pipe Bypass / Valving-Off
• The second in situ option, if space allows, is to redirect the flow through a bypass pipe section
or valve off the meter in order to isolate the meter's sensor in the place where it has been
installed. While the flow is redirected, the Zero CAL-CHECK™ test can be performed. Once the
test is complete, the valves to the bypass may be closed and flow may be directed back to the
meter's sensor where flow monitoring can continue as normal.

Achieving Zero Flow - Out-of-Pipe

If space limitations prevent in situ testing at zero flow as listed above, then out-of-pipe testing must
be performed.

With this configuration, the meter must be removed from the process, the test performed, and then
the meter returned to the process after testing has been completed.

Due to the high sensitivity of the PowerPro™ sensor, it is necessary to isolate the sensor once the
meter has been removed from the pipe. Therefore, Fox Thermal provides a sensor cover when the
meter is shipped to the customer. An alternative to the sensor cover is to use a bottle or other closed
container in order to isolate the sensor and achieve the "no flow" condition necessary to perform the
Zero CAL-CHECK™ test.

Operation | 78
 Model FT3
Operation

Fig. 4.5: Fox Thermal-Supplied PVC Sensor Protector vs. Plastic Bottle

NOTE! For best results:

•Use the factory-supplied PVC sensor protector shipped with the meter (see Fig. 4.5).
•Place the meter upside-down on a flat, solid surface before starting the test.
•Do not allow the meter to get moved - make sure the meter is stable and the sensor
completely isolated.

Using a Fox Thermal Retractor for Zero CAL-CHECK™

The following are the instructions for using a Fox Thermal retractor to set the field baseline for - or
performing - an in situ Zero CAL-CHECK™ test. If you are not using a Fox Thermal retractor, move
ahead to "Starting the Field Baseline Set" on p. 83.

NOTE! If you need information on the installation of the Fox Thermal retractor, refer to
"Installation of a New Retractor Assembly" on page 29.

Operation | 79
Model FT3
Operation

Fig. 4.6: FT3 and Parts of Fox Thermal Retractor

F1 F2 F3 F4

Fig. 4.7: Close-Up: Fittings of Fox Thermal Low Pressure Retractor

PAGE 10
COMPRESSION NUT, 7/8" WRENCH

FITTING HEX, 7/8" WRENCH

PAGE 10 Operation | 80
 Model FT3
Operation

To isolate the sensor, it must be retracted from the pipe.

WARNING! SYSTEM MAY BE UNDER HIGH PRESSURE. Do not attempt to remove meters
from a pipe pressurized above 60 psig without first relieving pressure in the pipe.

WARNING! When removing the flow meter, be sure to hold the electronics enclosure firmly
by hand before unscrewing the compression fitting nut. Failure to do this will allow the
pressure in the pipe to suddenly and rapidly force the meter from the pipe potentially causing
serious injury. The meter could also be damaged resulting in a loss of gas from the pipe. The
force required to hold the meter will be 0.20 times the pipe pressure. If you are unsure of your
ability to hold the meter for any reason, do not loosen the compression fitting nut.

Loosen the compression nut of the compression fitting using two 7/8" wrenches. Once loosened, the
probe will be able to slide out (see Fig. 4.8 below).

Fig. 4.8: Loosening the Compression Fitting

ch
en
wr
8”
7/

Compression Nut

Adjacent Hex
13
/16
”w
ren
ch

With one hand supporting the meter, slide the probe up through the retractor until the internal stop
makes contact. Close the valve shut-off handle by turning the lever 90˚clockwise to isolate the sensor
within the chamber of the retractor (see figure 4.9).

Operation | 81
Model FT3
Operation

Fig. 4.9: Isolating the Sensor in Retractor Chamber

F1 F2 F3 F4

Turn handle clockwise

90° to close valve

Lift to unlock
handle

PROBE INSIDE
RETRACTOR

PAGE 12
After diagnostic procedure is complete, the probe must be reinserting into the pipe to begin
monitoring flow again. When the test has been completed, carefully open shut-off valve, slide the
meter down until the ferrules rest in the fitting, and tighten the compression fitting nut on the fitting
to seal the probe in the stream.

Check that the meter has returned to normal operation.

Operation | 82
 Model FT3
Operation

Setting Field Baseline for In Situ Zero CAL-CHECK™ Tests

After calibration of every FT3 meter, a lab technician sets the factory baseline for Zero CAL-CHECK™
tests. If you are planning on removing the meter from the process to perform the test, you do not
have to set the baseline; however, if you plan to perform the test in situ (in the pipe) or using a Fox
Thermal retractor, you must set the field baseline before performing the test.

When the sensor is isolated in zero flow, the FT3 meter is ready to either perform the Zero CAL-
CHECK™ test or set the field baseline for future tests.

Starting the Field Baseline Set

After the meter has been installed and wired correctly (see Wiring section of this manual), power on
the meter.
The meter should default to display #1. Press "F1" to program the meter. Press Yes (F1) to set
parameters and you will be prompted to enter the password. Use a Level 2 password (9111). The
display will show:

SET PARAMETERS
I/O FLO DSP EXIT

F1 F2 F3 F4

Press FLO (F2) to go to the FLOW PARAMETER 1 menu.

FLOW PARAMETER 1
DGN UNT PRM EXIT

F1 F2 F3 F4

Press DGN (F1) to go to the DIAGNOSTIC menu.

DIAGNOSTIC
SIM TEST EXIT

F1 F2 F3 F4

Press TST (F2) to get to the Diagnostic Test Sub-Menu.

DIAGNOSTIC
CALV ZRO EXIT

F1 F2 F3 F4

Choose ZRO (F2) for Zero CAL-CHECK™.

Operation | 83
Model FT3
Operation

ZERO CHK MENU

PIP BTL EXIT

F1 F2 F3 F4

Choose PIP (F1) for in situ Zero CAL-CHECK™.

ZERO PIPE TEST

VER SET PRM EXIT

F1 F2 F3 F4

To set the field baseline, choose SET (F2).

SET ZRO Ref?

YES NO

F1 F2 F3 F4

Choose YES (F1) to set the field baseline.

Process Zero and

Stable? YES

F1 F2 F3 F4

NOTE! At this point, you must make sure that there is a no flow condition in the pipe (see
"Techniques for Achieving Zero Flow - In the Pipe" on p. 78). Also be sure that the meter
will be stable for the duration of the setting process.

If there is no flow and the meter is stable, press YES (F4). The display will show:

Setting ZRO ref

ZR=x.xxxxx T=xx

F1 F2 F3 F4

As the meter is setting the field baseline, the meter will display the reference value for the Zero
baseline (ZR=xx.xxxx) and a countdown timer (T=xx) to approximate the time until the completion of
the set. Depending on the meter configuration, the set may take between 5-15 minutes to complete.

NOTE! Do not interrupt the set by touching the meter or changing conditions in the pipe.
Changing the meter setup may affect the accuracy of the baseline.

Operation | 84
 Model FT3
Operation

At the conclusion of the set, the display will show:

Ref=x.xxxx
OK

F1 F2 F3 F4

Press OK (F4) to return to the Zero CAL-CHECK™ menu.

The meter may now perform Zero CAL-CHECK™ tests at the field baseline at any time.

Performing the Zero CAL-CHECK™ Calibration Validation Test - In the Pipe

Press FLO (F2) from the SET PARAMETERS menu. The display will show:

FLOW PARAMETER 1
DGN UNT PRM EXIT

F1 F2 F3 F4

Press DGN (F1). The display will show:

DIAGNOSTIC
SIM TST EXIT

F1 F2 F3 F4

Press TST (F2). The display will show:

DIAGNOSTIC
CALV ZRO EXIT

F1 F2 F3 F4

Press ZRO (F2) to enter the Zero CAL-CHECK™ menu.

If performing the test in the pipe, a "no flow" condition must be met. If performing the test in
the pipe, a "no flow" condition must be created. If performing out of the pipe, the meter must be
removed and the sensor covered by a bottle or the PVC sensor protector.

ZERO CHK MENU

PIP BTL EXIT

F1 F2 F3 F4

Operation | 85
Model FT3
Operation

NOTE! For accurate readings and best test results:

• Perform a visual inspection of sensor window for damage/deformity and condition of
sensor elements before starting the test.
• The meter must be used in the same pipe size, with the same gas mixture, and in the same
process conditions for which the meter was originally calibrated in the factory. Consult
the original factory calibration certificate for details.

Press PIP (F1) to choose to perform the test in the pipe. The display will show:

ZERO PIPE TEST

VER SET PRM EXIT

F1 F2 F3 F4

Press VER (F1) key to verify the Zero CAL-CHECK™.

VERIFY ZRO?
YES NO

F1 F2 F3 F4

Press YES (F1) key to verify the Zero CAL-CHECK™.

Process Zero and

Stable YES

F1 F2 F3 F4

WARNING! If you are using "Pipe" test, you must verify that there is a no flow condition
before proceeding. If you are performing the test in a bottle, be sure to isolate the sensor in a
bottle - any air movement (even from a fan) can result in a false "fail" result.

Once process is stable, press YES (F4) key to begin the Zero CAL-CHECK™.

Verifying ZRO
Diff = xx.xx T=xx

F1 F2 F3 F4

This test will take less than 5 minutes. The T=xx is a count down timer indicating how much time is
left to finish the test.

Operation | 86
 Model FT3
Operation

Diff=x.xxx %
Passed OK

F1 F2 F3 F4

Upon test completion, the final percentage value will be displayed along with a Pass/Fail message.

Performing the Zero CAL-CHECK™ - Out-of-pipe

Remove the meter from the pipe and isolate in an area that will allow the test to go undisturbed (see
Note below).

Press FLO (F2) from the SET PARAMETERS menu. The display will show:

FLOW PARAMETER 1
DGN UNT PRM EXIT

F1 F2 F3 F4

Press DGN (F1). The display will show:

DIAGNOSTIC
SIM TST EXIT

F1 F2 F3 F4

NOTE! For best results:

•Use the factory-supplied PVC sensor protector (see Fig. 4.5 on p. 79).
•Place the meter upside-down on a flat, solid surface before starting the test.
•Do not allow the meter to move during the test. Make sure the sensor is stable and the
sensor is completely isolated throughout the test.

Press TST (F2). The display will show:

DIAGNOSTIC
CALV ZRO EXIT

F1 F2 F3 F4

Press ZRO (F2) to choose the type of Zero CAL-CHECK™ test.

ZERO CHK MENU

PIP BTL EXIT

F1 F2 F3 F4

Operation | 87
Model FT3
Operation

Press BTL (F2) to choose to perform the test out of the pipe. The display will show:

ZERO BTL TEST

VER EXIT

F1 F2 F3 F4

Press VER (F1) key to verify the Zero CAL-CHECK™.

VERIFY ZRO?
YES NO

F1 F2 F3 F4

Press YES (F1) key to verify the Zero CAL-CHECK™.

Process Zero and

Stable? YES

F1 F2 F3 F4

WARNING! You must verify that there is a no flow condition before proceeding. Be sure to
isolate the sensor completely - any air movement (even from a fan) can result in a false "Fail"
result.

Once process is stable, press YES (F4) key to begin the Zero CAL-CHECK™.

Verifying ZRO Verifying ZRO

Diff = xx.xx T=xx Sd = xx.xx T=xx

F1 F2 F3 F4 F1 F2 F3 F4

This test will take less than 5 minutes. The display will alternate between the standard deviation
measurement value and the T=xx count down timer indicating how much time is left to finish the test.

Diff=x.xxx %
Passed OK

F1 F2 F3 F4

Upon test completion, the final value will be displayed along with a Pass/Fail message.

Operation | 88
 Model FT3
Operation

Enabling/Disabling the Infrared Keypad (IR keys)

The IR keys may be disabled using this menu to avoid being triggered by frost or snow on the
window. This menu is accessed by pressing DSP (F3) from the SET PARAMETERS menu then IR (F2):

IR KEY= Enabled
NXT OK

F1 F2 F3 F4

Press NXT (F1) key to enable or disable the IR keys.

NOTE! After selecting “Disable” and pressing OK (F4), the IR keys will no longer operate. It
will be necessary from now on to open the cover and operate the configuration panel using
the mechanical push buttons. To return to the normal display mode, use the mechanical
buttons to enable the IR keys.

NOTE! The IR keys are disabled for 1 minute when a mechanical key is used, to prevent
accidentally activating the IR keys.

Calibrating the Infrared Keypad (IR keys)

The IR keys are calibrated in the factory before shipment, but conditions in the field may alter the way
the keys read. To allow the IR keys to perform better, it may be necessary to calibrate the keys in the
field.

Use your finger to activate the IR keys using this process.

NOTE! Your finger must activate each key approximately 0.1” to .5” from the surface of the
glass.

To begin the IR key calibration process, turn off power to the FT3 and then turn on power while
placing your fingers on the (F3) and (F4) IR keys at the same time. Activate IR key (F1) to confirm to
begin the IR key calibration. Hold your finger over IR key (F1). In 10 seconds the power level of the IR
key (F1) will be displayed and automatically increase until activation is detected. This will be repeated
for calibration of the (F2), (F3) and (F4) keys.

To check the calibration values of the IR keys, turn off power to the FT3, then turn on power to the FT3
while placing your finger on the (F1) IR key. The display will show the values (example here):

IR = 3,3,3,3

F1 F2 F3 F4

Operation | 89
Model FT3
Communications

Scope - Modbus Communications

This portion of the manual describes the Modbus implementation using RS485 serial communication
physical layer for the Fox Thermal FT3 mass flow meter based on the Modicon Modbus Protocol (PI-
MBUS-300 Rev. J). A Modbus-enabled FT3 includes "MB" in the model number.

Modbus Protocol
Modbus Protocol is an application layer messaging protocol that provides client/sever
communications between devices. Modbus is a request/reply protocol and offers services specified by
function codes.

The size of the Modbus Protocol Data Unit is limited by the size constraint inherited from the first
Modbus implementation on Serial Line network (max. RS485 Application Data Unit = 256 bytes).
Therefore, Modbus PDU for serial line communication = 256 – Server address (1 byte) – CRC (2 bytes)
= 253 bytes.

RS485 ADU = 253 + Server address (1 byte) + CRC (2 bytes) = 256 bytes.

For more information on Modbus go to the web site http://www.modbus.org/.

Command Request:
<Meter Address> <Function code> <Register start address high> <Register start address low>
<Register count high> <Register count low> <CRC high> <CRC low>

Command Response:
<Meter Address> <Function code> <Data byte count> <Data register high> <Data register
low> ... <Data register high> <Data register low> <CRC high> <CRC low>

NOTE! The data shown in brackets < > represents one byte of data.

Modbus Indicators
Orange LED indicator LP2 blinks when Modbus signals are received and yellow LP1 blinks when
Modbus signals are transmitted. The LEDs are located on the Modbus communication board next to
the wiring connections.

Modbus Function Codes Supported by the FT3

The FT3 supports the following commands:
1) Command 03: Read multiple registers
2) Command 04: Read single register.
3) Command 06: Write single register

Communications | 90
 Model FT3
Communications

Read Multiple Registers (command 03)

This command reads one or more 16-bit registers from the FT3 and has the following format:

Request:
<Meter Address> <Command code=03> <Register start address high> <Register start address
low> <Register count high> <Register count low> <CRC high> <CRC low>

Response:
<Meter Address> <Command code=03> <Byte count> <Data high><Data low> ... <Data
high><Data low> <CRC high> <CRC low>

Example: Request data register at starting address 0x0000 and specifying 1 register

<0x01> <0x03> <0x00> <0x00> <0x00> <0x01> <0x0a> <0x84>

Response:
<0x01> <0x03> <0x02> <xx> <xx> <CRC high> <CRC low>

Where xx xx is the data register value.

Table 5.1: FT3 Modbus Registers

Modbus Data Type Description Units

Register
40001 32-bit int LSW Flow User selected
40002 32-bit int MSW
40003 32-bit int LSW Total User selected
40004 32-bit int MSW
40005 32-bit int LSW Temperature x 10 User selected
40006 32-bit int MSW
40007 32-bit int LSW Elapsed time x 10 Hours
40008 32-bit int MSW
40009 32-bit int LSW Flow Velocity Meters/hour
40010 32-bit int MSW
40011 * 16-bit int Flow x 10 User selected /10
40012 * 16-bit int Flow x 100 User selected /100
40013 * 16-bit int Total x 100 User selected /100
40014 32-bit int LSW Total2 (2 gas curves only) User selected
40015 32-bit int MSW
40016 16-bit int Status
40017 16-bit int Status 2
40018 16-bit int Reserved
40019 16-bit int Reserved

*To get the actual value of registers 40011-40013, divide the presented value by 10 or 100.

Communications | 91
Model FT3
Communications

Table 5.1: FT3 Modbus Holding (cont'd)

Modbus Data Type Description Units
Register
40020 32-bit float LSW Flow User selected
40021 32-bit float MSW
40022 32-bit float LSW Total User selected
40023 32-bit float MSW
40024 32-bit float LSW Total 2 (2 gas curves only) User selected
40025 32-bit float MSW
40026 32-bit float LSW Temperature User selected
40027 32-bit float MSW
40028 32-bit float LSW Elapsed Time Hours
40029 32-bit float MSW
40030 32-bit float LSW Flow Velocity Meters/hour
40031 32-bit float MSW
40032 32-bit float LSW CAL-V Diff CAL-V Diff
40033 32-bit float MSW
40034 32-bit float LSW CAL-V Set CAL-V Set
40035 32-bit float MSW
40036 16-bit int Reserved
40037 32-bit int LSW Total 24 hrs, Last total record User selected
40038 32-bit int MSW
40039 16-bit int Total 24 hrs, Current Day (0-6) Day
40040 16-bit int Total 24 hrs, Current Hour (0-23) Hour
40041 32-bit int LSW Total 24 hrs, Record day 1 User selected
40042 32-bit int MSW
40043 32-bit int LSW Total 24 hrs, Record day 2 User selected
40044 32-bit int MSW
40045 32-bit int LSW Total 24 hrs, Record day 3 User selected
40046 32-bit int MSW
40047 32-bit int LSW Total 24 hrs, Record day 4 User selected
40048 32-bit int MSW
40049 32-bit int LSW Total 24 hrs, Record day 5 User selected
40050 32-bit int MSW
40051 32-bit int LSW Total 24 hrs, Record day 6 User selected
40052 32-bit int MSW
40053 32-bit int LSW Total 24 hrs, Record day 7 User selected
40054 32-bit int MSW
40055 32-bit int LSW Total 24 hrs, Last Total User selected
40056 32-bit int MSW
40057 32-bit float LSW Zero Check Mean Zero Check Mean value
40058 32-bit float MSW
40059 32-bit float LSW Zero Check Stdev Zero Check Standard Deviation
40060 32-bit float MSW

Communications | 92
 Model FT3
Communications

Table 5.1: FT3 Modbus Holding (cont'd)

Modbus Data Type Description Units

Register
40061 32-bit float LSW Zero Check Pipe Ref Zero Check Pipe Reference
40062 32-bit float MSW
40063 32-bit float LSW Zero Check Pipe Diff Zero Check Pipe Difference %
40064 32-bit float MSW
40065 32-bit float LSW Zero Check Bottle Ref Zero Check Bottle Reference
40066 32-bit float MSW
40067 32-bit float LSW Zero Check Bottle Diff Zero Check Bottle Difference %
40068 32-bit float MSW
40069 16-bit int Zero Check Test Time Zero Check Test Time (seconds)

NOTES!
• In the table, LSW means Least Significant Word, and MSW means Most Significant Word.
In this case a “word” is one 16-bit Modbus register. A 32-bit float or 32-bit integer is
stored in a pair of Modbus registers. When a register is designated as “32-bit int LSW”, it
means that bits 0-15 of the variable are in that register. A register designated as MSW has
bits 16-31 of the variable. For instance, the flow total can be read as a 32-bit integer from
registers 40003 (LSW) and 40004 (MSW). If the flow total is 0x12345678, then register
40003 will hold 0x5678, and register 40004 will hold 0x1234.
• 32-bit floating point values are defined by the IEEE 754 standard: https://ieeexplore.ieee.
org/document/8766229
• Refer also to Wikipedia: https://en.wikipedia.org/wiki/Single-precision_floating-point_
format

Example:
Request data register at starting address 0x0000 and specifying only 1 register:
<0x01> <0x03> <0x00> <0x00> <0x00> <0x01> <0x0a> <0x84>

Command Response
<0x01> <0x03> <0x02> <xx> <xx> <CRC high> <CRC low>
Where xx is the data register value.

Communications | 93
Model FT3
Communications

Read Single Register (Command 04)

This command is used to report the status information.

Request:
<Meter Address> <Command code=04> <Register address =0> <Register address =0> <Register
count =0> <Register count =1> <CRC high> <CRC low>

Response:
<Meter Address> <Command code=04> <Byte count =2> <Status High><Status Low> <CRC
high> <CRC low>

Table 5.2: Status Bits Definitions for Command 04, Modbus Address 30001
Bit Definition Comment
0 Power up indication Cleared when out of the power up sequence
1 Flow rate reached high limit threshold Set limit to zero to disable
2 Flow rate reached low limit threshold Set limit to zero to disable
3 Temperature reached high limit threshold Set limit to zero to disable
4 Temperature reached low limit threshold Set limit to zero to disable
5 Sensor reading is out of range Check sensor wiring
6 Velocity flow rate outside of calibration table Check sensor wiring
7 Incorrect Settings Check settings
8 In simulation mode Set simulation value to 0 to disable
9 Pulse output is out of range Check pulse output settings
10 Analog CH1 4-20mA is out of range Check analog output settings
11 Analog CH2 4-20mA is out of range Check analog output settings
12 Anybus error Replace display board
13 Bridge Shut Down Check sensor wiring
14 CRC error Check parameters and reset CRC
15 Error in Total Reset total to clear alarm

Table 5.3: Status 2 Bits Definitions for Command 04, Modbus Address 30002
Bit Definition
0 CAL-V in progress
1 ADC12<> ADC24 too far apart, internal calibration out of range
2 CAL-V Diff out of range
3 Curve #2 Selected (for 2 gas curves only)
4 Zero Check failed
5 CAL-V/Zero Check aborted

Communications | 94
 Model FT3
Communications

Write Single Register (Command 06)

This command is used to perform miscellaneous functions such as clearing the totalizer and initiating
diagnostic operations. The register address is 0x0a (10 decimal, Modbus=40011) and the data to write
is described below.

Request:
<Meter Address> <Command code=06> <Register address high=0x00> <Register address
low=0x0a> <Register data high=0x00> <Register data low =0x02> <CRC high> <CRC low>

Response:
<Meter Address> <Command code=06> <Register address =0x00> <Register address =0x0a>
<Register data=0x00> <Register data =0x02> <CRC high> <CRC low>

Reset Total:
Address = 40011, data = 0x02
This command is used to clear the Totalizer and elapsed time registers

Reset 24 hours Total:

Address=40011, data = 180 (0xB4)
This command resets the 24 hours 7 days record including the day and hours counters

Reset 24 hour time:

Address=40011, data = 181 (0xB5)
This command resets the 24 hours day and hours counters.

24 hours Event:
Address=40011, data = 182 (0xB6)

This command generates a 24 hours event, the same way as when the 24 hours counter rolls over.
This may be useful to record total over a shorter period.

CAL-V Verify:
Address=40011, data = 161 (0xA1)

This command initiates a "CAL_V Verify". This operation may take 4 minutes to complete and
will stop the meter from calculating flow. The Status2 bit D0 may be monitored to check for
completion.

Zero Check In-Pipe Verify:

Address=40011, data = 173 (0xAD)

This command initiates a "Zero Check In-Pipe Verify". This operation does not affect flow
calculations. The register 40069 may be monitored to check for completion.

Communications | 95
Model FT3
Communications

Zero Check In-Bottle Verify:

Address=40011, data = 176 (0xB0)

This command initiates a "Zero Check In-Bottle Verify". This operation does not affect flow
calculations. The register 40069 may be monitored to check for completion.

Switch to Curve #1:

Address=40011, data = 170 (0xAA)

This command initiates a command to switch to gas curve 1 when configured for 2 gas curves.
Make sure that the input contact is not programmed for curve switching

Switch to Curve #2:

Address=40018, data = 171 (0xAB)

This command initiates a command to switch to gas curve 2 when configured for 2 gas curves.
Make sure that the input contact is not programmed for curve switching.

Select Record (command 06, Preset Register, Modbus Address 40214)

This command is used to select the next record that is going to be read from the data log buffer using
command 03.
Address register = 40214
Data = xx. (xx = record select (hex 0-1e, decimal 0-30)

NOTE! Record 0 is the latest and 30 is the oldest.

Request:

<Meter Address> <Function code=06> <Register address high=0x00> <Register address low=0xd5>
<Register data high=0x00> <Register data low =0xx> <CRC high> <CRC low>

Response:

<Meter Address> <Function code=06> <Register address =0x00> <Register address =0xd5>
<Register data=0x00> <Register data =0xx> <CRC high> <CRC low>

Read Record (command 03, Read Holding register)

These registers are used to get the data for a single record. Before issuing that command, a preset
command has to be sent to select the record to be read.

NOTE! The Record Number is an unsigned integer (0-65535) that is incremented every time a
new record is stored and is not the same as the request record number (0-30).

Communications | 96
 Model FT3
Communications

Example:
Request:

Request data register at starting address 40200 and specifying 9 register to read the complete record

<0x01> <0x03> <0x00> <0xc7> <0x00> <0x09> <0x34> <0x31>

Response:

<0x01> <0x03> <0x12> <rec nb> <rec nb> <year><month><day><hour><min><sec><data

index><data index><total val int><total val int><total val int><total val int><total val fp><total val
fp><total val fp><total val fp><CRC high> <CRC low>

Register Modbus Data Type Comment

Address Address
0xc7 40200 Record Number (16 bits integer) Record Number
0xc8 40201 Year /Month (16 bits integer, BCD format yyyy mmmm) Record Year/Month
0xc9 40202 Day/Hour (16 bits integer, BCD format dddd hhhh) Record Day/Hour
0xca 40203 Minute/Second (16 bits integer, BCD format mmmm 0000) Record Minute/
sec=0
0xcb 40204 Data Index (16 bits integer, 0x00FA)) Data Index = 250
0xcc 40205 Interval Total (16 bits unsigned integer, high register) Interval Total (int)
0xcd 40206 Interval Total (16 bits unsigned integer, low register) Interval Total (int)
0xce 40207 Interval Total (float upper 16 bits) Interval Total (float)
0xcf 40208 Interval Total (float lower 16 bits) Interval Total (float)

Clear Data Log (command 06, Preset Register, Modbus Address 40213)
This command is used to clear all records in the log.
Address register = 40213
Data = 0x57.

Request:

<Meter Address> <Function code=06> <Register address high=0x00> <Register address low=0xd4>
<Register data high=0x00> <Register data low =0x57> <CRC high> <CRC low>

Response:

<Meter Address> <Function code=06> <Register address =0x00> <Register address =0xd4>
<Register data=0x00> <Register data =0x57> <CRC high> <CRC low>

Communications | 97
Model FT3
Communications

Floating point data layout

Each 32-bit floating point value uses two consecutive Modbus registers. The most significant byte of
the lower numbered register holds the least significant byte of the significand. The least significant
byte of the lower numbered register holds the next most significant byte of the significand. The most
significant byte of the higher numbered register holds the sign bit and most significant 7 bits of the
exponent. The least significant byte of the higher numbered register holds the least significant bit of
the exponent and the most significant 7 bits of the significand.

In the following tables:

S0 – S23 are the significand bits from least to most significant.
E0 – E7 are the exponent bits from least to most significant.
Sign is 1 if the number is negative, and 0 if the number if positive.

Lower numbered register

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
S15 S14 S13 S12 S11 S10 S9 S8 S7 S6 S5 S4 S3 S2 S1 S0

Higher numbered register

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Sign E7 E6 E5 E4 E3 E2 E1 E0 S22 S21 S20 S19 S18 S17 S16

Since the Modbus register data is sent most significant byte first and the registers are sent lowest
numbered first, a floating point value will look like this in the data stream:

First byte (MSB of lower register)

Data bit 7 6 5 4 3 2 1 0
Value bit S15 S14 S13 S12 S11 S10 S9 S8

Second byte (LSB of lower register)

Data bit 7 6 5 4 3 2 1 0
Value bit S7 S6 S5 S4 S3 S2 S1 S0

Third byte (MSB of higher register)

Data bit 7 6 5 4 3 2 1 0
Value bit Sign E7 E6 E5 E4 E3 E2 E1

Fourth byte (LSB of higher register)

Data bit 7 6 5 4 3 2 1 0
Value bit E0 S22 S21 S20 S19 S18 S17 S16

Communications | 98
 Model FT3
Communications

Modbus Parameters
To program the communication parameters, start at the SET PARAMETERS menu:

SET PARAMETERS
I/O FLO DSP EXIT

F1 F2 F3 F4

Then press I/O (F1) to set Inputs/Outputs:

SET I/O
COM I/O 420 EXIT

F1 F2 F3 F4

Then press COM (F1) to select communication parameters.

Set Bus protocol for Modbus:

Comm=Modbus
NXT OK

F1 F2 F3 F4

Press NXT (F1) repeatedly until Modbus is selected as shown and then press OK (F4) to accept the
setting.

The following communication settings apply only to Modbus:

Baud=9600
NXT OK

F1 F2 F3 F4

Press NXT (F1) repeatedly until the correct selection is shown then press OK (F4) to accept the
setting.
Selections are: 115200 9600
76800 4800
57600 2400
38400 1200
19200

Communications | 99
Model FT3
Communications

Parity=EVEN
NXT OK

F1 F2 F3 F4

Press NXT (F1) repeatedly until the correct selection is shown and then press OK (F4) to accept the
setting.

Selections are: NONE

ODD
EVEN

Address=02
CHG OK

F1 F2 F3 F4

Press CHG (F1) to change the address and then press OK (F4) to accept the setting.

Selections are between 01 and 247.

NOTE! Power cycle is required for the new settings to take effect.

Communications | 100
 Model FT3
Communications

Scope - HART Communications

The Fox Thermal model FT3 transmitter complies with HART Protocol Revision 7.1. A HART-enabled
FT3 includes "BH" in the model number. This section of the manual specifies all the device-specific
features and documents HART Protocol implementation details (e.g., the Engineering Unit Codes
supported). The functionality of this Field Device is described sufficiently to allow its proper
application in a process and its complete support in HART-capable Host Applications.

Purpose
This specification provides a complete description of this Field Device from a HART Communication
perspective. The specification is designed to be a technical reference for HART capable Host
Application Developers, System Integrators and knowledgeable End Users. It also provides
functional specifications (e.g., commands and performance requirements) used during development,
maintenance and testing. This document assumes the reader is familiar with HART Protocol
requirements and terminology.

References
HART Smart Communications Protocol Specification. HCF_SPEC-12.

Device Identification

Manufacturer Name: Fox Thermal Instruments Model Name: FT3

Manufacture ID Code: 24635 (603b hex) Device Type Code: 57583 (E0EF Hex)

HART Protocol Revision: 7.1 Device Revision: 1

No. of Device Variables: None

Physical Layers
FSK
Supported:
Physical Device Transmitter, DC-isolated Bus
Category: Device

Product Overview
The FT3 HART communication option can be monitored and configured using a HART master device
or a hand-held communicator.

Communications | 101
Model FT3
Communications

Process Flow Rate 4-20mA Analog Output

The 4-20mA output of the FT3 HART represents the process flow rate measurement, linearized and
scaled according to the configured range of the instrument. This output corresponds to the Primary
Variable. HART Communication is supported on this loop.

Channel 2 of the 4-20mA output may be configured for flow or temperature values when using HART.

HART Indicators
Green LED indicator LP3 cycles on and off to indicate that the FT3 is operating. Orange LED indicator
LP2 blinks when HART signals are received and Yellow LP1 blinks when HART signals are transmitted.
The LEDs are located on the HART communication board next to the wiring connections.

The orange LED indicator LP2 will be on continuously when HART communication is enabled and the
4-20mA wiring is not connected.

FT3 HART Communication Setup

HART communication must be selected in the FT3 Serial Communication menu for HART
communication to operate. When this communication parameter is changed, power to the FT3 must
be cycled for it to take effect.

HART Parameters
To program the communication parameters, press I/O (F1) key from the SET PARAMETERS menu.

SET PARAMETERS
I/O FLO DSP EXIT

F1 F2 F3 F4

Choose I/O (F1) to access the communication output.

SET I/O
COM PUL 420 EXIT

F1 F2 F3 F4

Then press COM (F1) to select communication parameters.

Set Bus protocol for HART:

Comm=HART
NXT OK

F1 F2 F3 F4

Press NXT (F1) until HART is selected as shown and then press OK (F4) to accept the setting.

Communications | 102
 Model FT3
Communications

NOTE! Power cycle is required for the new settings to take effect.

Device Variables
This device does not expose any Device Variables.

Dynamic Variables
Four Dynamic Variables are implemented.
Variable Meaning Units
PV Flow Rate In Selected Units
SV Total In Selected Units
TV Temperature In Selected Units
QV Elapsed Time In Hours

Status Information
Device Status
Bit 4 ("More Status Available") is set when any failure is detected. Command #48 provides additional
detail.

Extended Device Status

This bit is set if a sensor error is detected. "Device Variable Alert" is set if the Primary Variable (PV) is
out of limit.

Communications | 103
Model FT3
Communications

Additional Device Status (Command 48)

Command #48 returns 2 Device-Specific Status bytes of data, with the following status information:
These bits are set when an alarm or error condition is present. The bit automatically clears when the
condition returns to its normal state.

Byte Bit Meaning Class

0 0 Power Up Indication Status
1 High Flow Limit Alarm Alarm
2 Low Flow Limit Alarm Alarm
3 High Temperature Limit Alarm Alarm
4 Low Temperature Limit Alarm Alarm
5 Sensor out of range Error
6 Velocity out of range Error
7 Check Parameter Settings Error

1 0 In Simulation Mode Alarm

1 Pulse output out of range Alarm
2 CH 1 4-20mA out of range Alarm
3 CH 2 4-20mA out of range Alarm
4 Busy Alarm
5 Bridge shutdown Error
6 CRC database error Error
7 Error with Total Error

Common-Practice Commands, Supported Commands

The following common-practice commands are implemented:
34 Write Primary Variable (PV) Damping Value
35 Write PV Range Value
36 Set PV Upper Range Value
37 Set PV Lower Range Value
38 Reset "Configuration Changed" Flag
40 Enter/Exit Fixed Current Mode
44 Write PV Units
45 Trim Loop Minimum
46 Trim Loop Maximum
48 Read Additional Device Status (Command #48 returns 2 bytes of data)
59 Write Number of Response Preambles

Communications | 104
 Model FT3
Communications

Common-Practice Commands, Unsupported Commands

Burst Mode - This device does not support Burst Mode.
Catch Device Variable - This device does not support Catch Device Variable.
Device-Specific Commands - No Device-Specific commands are implemented.

Modes
Fixed current mode is implemented, using Command 40. This mode is cleared by power loss or reset.

Damping
Damping is standard, affecting only the PV and the loop current signal.

Capability Checklist

Manufacturer, model Fox Thermal Instruments, FT3

Device Type Transmitter
HART revision 7.1
Device Description available No
Number and type of sensors 1
Number and type of actuators 0
Number and type of host side signals 1 : 4-20mA analog
Number of Device Variables 0
Number of Dynamic Variables 4
Mappable Dynamic Variables No
Number of common-practice commands 17
Number of device-specific commands 0
Bits of additional device status 8
Alternative operating modes No
Burst mode No
Write-protection Yes

Communications | 105
Model FT3
Data Logger

Scope - Data Logger

The model FT3 offers an option to have a data logger mounted on the Front Panel board that can be
used to record FT3 data. A Data Logger-enabled FT3 includes "DL" in the model number. Data that
may be recorded includes interval totals (i.e. a previous 24-hour total) based on selected flow units
(i.e. total mass flow or total volumetric flow). This data may be recorded at a rate specified by the
customer ranging from 1 second to 1 month in hour/minute/second intervals.

This section of the manual contains the operation instructions for the FT3 data logger. The FT3 data
logger supports 31 records with a start/sync time of midnight set as a default. When the number of
samples exceeds 31, the oldest data will be overwritten. Only the most recent 31 records are kept.

Model FT3 Data Logger Features

The following features are included in the data logger option available on the Fox Thermal model FT3
thermal gas mass flow meter:

• 31 separate 24-hour daily totals with date and time stamp

• Data can be accessed over Modbus RTU (RS485) and the engineering display
• After 31 days, old data will be overwritten; however, the most recent 31 daily totals will always be
available
• The operator may set the start time through the front panel (the default start time for the 24-hour
total will be midnight)
• Operator may set the local time through the front panel
• Field retrofits with data loggers require exchanging the existing display board for the display
board with the data logger feature and upgrading the main FT3 board firmware (upgrade kit
available)

Data Logger Setup Menu

Using the keypad on the front panel, enter the programming mode:

SET PARAMETERS
I/O FLO DSP EXIT

F1 F2 F3 F4

Press F1 for (I/O). The screen will show:

SET I/O
COM I/O 420 EXIT

F1 F2 F3 F4

Press F2 for (I/O). The screen will show:

Data Logger | 106

 Model FT3
Data Logger

SET I/O
INP OUT LOG EXIT

F1 F2 F3 F4

NOTE! If the hardware does not detect a real time clock, the LOG menu key will not be
displayed.

Press F3 for (LOG). The screen will show:

Data log = ON
NXT OK

F1 F2 F3 F4

The default is set with the data logger enabled, press F1 (NXT) to turn the data logger ON or OFF
(the default is ON).

Press F4 (OK) to continue.

DATA LOG
CLR STR TIM EXIT

F1 F2 F3 F4

Clearing the Data Log

From the data log menu, press F1 (CLR).

DATA LOG
CLR STR TIM EXIT

F1 F2 F3 F4

The screen will show:

Clear Log?
YES NO

F1 F2 F3 F4

Press F1 (YES) to confirm or F4 (NO) to cancel.

Data Logger | 107

Model FT3
Data Logger

Setting the Start/Sync Time

The start/sync time is used to start or syncing a data log sample. When a match is detected between
the real time clock and the start/sync time, the interval is reloaded. The Data Logger will be set to the
default of zero (midnight) and only the hour, minute, and second will be used for the trigger.

For example:
A settting of "day=00, hour=00, minute=00" will reload the interval every day at midnight.

From the data log menu, press F2 (STR). The screen will show:

Start Time = ON
NXT OK

F1 F2 F3 F4

Press F1 (NXT) to turn ON or OFF the Start/Sync Time and then press F4 (OK):

Day Start = 0
CHG OK

F1 F2 F3 F4

Press F4 (OK).

Hour Start = 0
CHG OK

F1 F2 F3 F4

Set the hour for which you want to start/sync time. When the Hour Start is set to zero, the default will
be for midnight. Press F4 (OK).

Min Start = 0
CHG OK

F1 F2 F3 F4

Set the minute for which you want to start/sync time. Press F4 (OK).

Set Start Time?

YES OK

F1 F2 F3 F4

Data Logger | 108

 Model FT3
Data Logger

Press F1 (YES) to set the start/sync time for Day:Hour:Minute.

NOTE! Make sure that the specified time has not been reached yet.

Setting the Real Time Clock

From the Data Log menu, press F3 (TIM). The screen will show:

Date/Time
SET VIEW EXIT

F1 F2 F3 F4

Press F1 (SET):

Year Set = 13
CHG OK

F1 F2 F3 F4

Press F1 (CHG) to change the years, F4 (OK) to continue.

Month Set = 10
CHG OK

F1 F2 F3 F4

Press F1 (CHG) to change the month, F4 (OK) to continue.

Day Set = 28
CHG OK

F1 F2 F3 F4

Press F1 (CHG) to change the day/date, F4 (OK) to continue.

Hour Set = 13
CHG OK

F1 F2 F3 F4

Press F1 (CHG) to change the hours, F4 (OK) to continue.

Data Logger | 109

Model FT3
Data Logger

Min Set = 45
CHG OK

F1 F2 F3 F4

Press F1 (CHG) to change the minutes, F4 (OK) to continue.

Sec Set = 55
CHG OK

F1 F2 F3 F4

Press F1 (CHG) to change the seconds, F4 (OK) to continue.

Sec Date/Time
YES NO

F1 F2 F3 F4

Press F1 (YES) to set the Date and Time.

NOTE! All real time clocks on FT3 data loggers are set to a default of California's Pacific
Standard Time. To sync the real time clock to your local time exactly, set the time slightly
ahead of your local, current time and wait for the current time to reach the set value before
pressing the F1 (YES) key to set the time.

Viewing the Real Time Clock

From the Data Log Menu, Press F3 (View) or press F1 and F3 at the same time from the regular
mode.

Date/Time
10/28/13 13:45:55
F1 F2 F3 F4

The current real time is displayed on line 2 and is updated every second. Press F4 to exit.

NOTE! The seconds will only be displayed if there is enough room available to do so.

NOTE! Time is displayed in military time.

Data Logger | 110

 Model FT3
Data Logger

Displaying Data Log Records

The data logger supports 31 records, record #1 being the latest recorded value and 31 being the
oldest.
From the normal operating mode, press F1 and F4 keys at the same time:

Data Log Rec #1

F1 F2 F3 F4

NOTE! Record #1 is the most recent interval total, record #31 is the oldest.

This display screen will appear for only 1 second and will then show:

10/07/13 15:54
ITOT= 152345.3

F1 F2 F3 F4

The Date and Time is displayed on line 1 and the interval total on line 2. The interval total is based on
the flow units selected in the meter (total mass flow or total volumetric flow).

Pressing F2 will display the next record, F1 will display the previous record.

Press F4 to exit to the normal mode at any time.

Data Logger | 111

Model FT3
Maintenance

PRECAUTIONS
WARNING! BEFORE ATTEMPTING ANY MAINTENANCE, TAKE THE NECESSARY SAFETY
PRECAUTIONS BEFORE REMOVING THE PROBE FROM THE DUCT (EXAMPLE: PURGE
LINES OF TOXIC AND/OR EXPLOSIVE GAS, DEPRESSURIZE, ETC...).
WARNING! EXPLOSION HAZARD. DO NOT REMOVE OR REPLACE COMPONENTS
OR FUSES UNLESS POWER HAS BEEN SWITCHED OFF WHEN A FLAMMABLE OR
COMBUSTIBLE ATMOSPHERE IS PRESENT.
WARNING! EXPLOSION HAZARD. DO NOT DISCONNECT EQUIPMENT WHEN A
FLAMMABLE OR COMBUSTIBLE ATMOSPHERE IS PRESENT.

Access to Electronics
Accessing electronics is not normally required for maintenance purposes. If a loose connection is
suspected, unscrew the rear cap of the meter to access the wiring terminations.

CAUTION! BE SURE POWER TO METER IS SWITCHED OFF BEFORE ATTEMPTING TO

ACCESS ELECTRONICS. If there is a problem and a loose connection is not found, please
contact Fox Thermal Customer Service for technical assistance at (831) 384-4300.

Broken or Damaged Probe

If the sensor is broken or damaged, the probe and electronics must be returned to the factory. A new
sensor will be installed and calibrated. Refer to "Returning Your Meter" on p. 136.

Flow Calibration and Calibration Validation

To ensure high accuracy of your model FT3 Flow Meter, Fox Thermal provides a full NIST traceable
calibration. It is recommended that the meter's accuracy be checked annually by performing the
CAL-V™ and Zero CAL-CHECK™ Calibration Validation tests.

Fuse Replacement
WARNING! Turn input power OFF before removing or installing a fuse. Use only
recommended fuse replacements.

Verify the fuse is defective by measuring it with an ohm Meter (two replacement fuses are provided
with each unit). Replacement fuse is Littelfuse part number 0454.750MR.

To replace the fuse:

The fuse F1 is located near the power terminal block and can be removed by using tweezers or
needle-nose pliers.

Sensor Cleaning
The sensor is insensitive to small amounts of residue, but continued use in dirty environments will
require periodic cleaning. To inspect the sensor, remove power from electronics and remove the unit
from the pipe or duct, exposing the sensor elements. If they are visibly dirty, clean them with water or
alcohol (ethanol) using an appropriate brush until they appear clean again. Even though the sensor
elements are rugged, avoid touching them with any solid object and use a light touch while cleaning
them.

Maintenance | 112
 Model FT3
Maintenance

Instructions for Removing and Inserting the Meter from a Pressurized Pipe using the Retractor

WARNING! Possible injury or damage to equipment may occur if the retractor is not used
correctly. Please read the following instructions carefully prior to using the retractor.

CAUTION! Never remove the compression fitting without first closing the ball valve and
bleeding off pressure inside of the retractor.

WARNING! When working with the retractor, do not stand or position any part of your body
in the path of the flow meter. An injury may occur if the probe is forced outward by system
pressure.

How to Remove the Meter from the Retractor (System Pressurized)

Step 1 - Remove the Probe from the Flow Stream

1. Disconnect power from the meter.

NOTE! At 125 psig of max system pressure, the probe will have approximately 25 lbs. of force
pushing it out.
2. Loosen the compression fitting nut using two 7/8" wrenches.
3. With one hand supporting the meter, unscrew the compression nut and slide the probe out of the
retractor until the internal stop halts the travel of the probe.
4. Close the ball valve all the way.

CAUTION! At this point there is still pressure inside of the retractor.

Fig. 7.1: Close Up of Compression Nut and Compression Fitting for Retractor

Compression Nut,
7/8" Wrench

Compression Fitting,
7/8" Wrench

Maintenance | 113
Model FT3
Maintenance

Step 2 - Remove the Probe from the Retractor Body

Fig. 7.2: Identification of Retractor Parts for the FT3

Flow Direction Arrow

Compression Nut

Compression Fitting

Nipple

Ball Valve

5. Continue supporting the meter while performing the following steps.

6. If the meter is to be completely removed from the system, disconnect the wiring to the meter.
7. Using a 7/8" wrench, slowly loosen the compression fitting approximately one turn or less until
the pressure in the retractor is completely relieved.
8. After relieving the pressure, unscrew the compression fitting from the end of the nipple.

Maintenance | 114
 Model FT3
Maintenance

9. Carefully slide the probe out of the retractor along with the fitting while supporting the meter as
it comes out. Be careful while handling the meter so the sensor does not get damaged.

How to Insert the Probe into the Flow Stream (Valve closed, System Pressurized)

WARNING! Never stand where your body or any part of it is in front of the meter. An injury
may occur if the probe is forced outward by the system pressure.

1. Apply a thin film of anti-seize compound on the compression fitting threads, if needed.
2. Push the probe into the retractor and tighten the compression nut by hand. Align the probe with
the flow by rotating the probe until the flow direction arrow on the probe fitting is aligned with
the centerline of the pipe, and points in the direction of flow (see Fig. 7.3).

Fig. 7.3: Flow Direction Arrow

3. Tighten the compression nut onto the compression fitting using a 7/8” wrench on the nut and a
7/8” wrench on the fitting.
4. Pressurize the system and check the retractor for leaks. Tighten any of the fittings that may need
it or seal any leaks that require it.
5. The system may be wired at this point. Refer to the wiring section of this manual for wiring
instructions for the electronics enclosure. Power may be applied only after the meter has been
properly wired according to the manual, and it is safe to do so.

Maintenance | 115
Model FT3
Troubleshooting

Troubleshooting
CAUTION! The electronics and sensor supplied by Fox Thermal are calibrated as a single
precision mass flow meter. Interchanging sensors will decrease the accuracy of the flow
meter. If you experience any problem with your model FT3 flow meter, call Fox Thermal
Customer Service Department, Technical Assistance at (831) 384-4300.
Problem Possible Cause(s) Action(s)
Meter keeps 1. Power supply 1. Measure power supply voltage to verify it is
power cycling 2. Malfunction in flow stable and within operating range (refer to
meter power supply specs on p. 124).
3. Electromagnetic 2. Check meter power cycles.
Interference (EMI) 3. Press and release F1 and F2 at the same time;
the display will enter Engineering screens.
4. Press F1 to get to screen #23; record power
cycle value.
5. Press F4 to return to normal operation; monitor
meter until problem returns.
6. Return to screen #23 to see if power cycles
have increased; microprocessor is resetting due
to EMI electrical noise entering the meter.
7. Check Power input and output cables
grounding and routing.
8. Return flow meter to Fox Thermal for repair
(refer to p. 136 for shipping instructions).

Flow measurement 1. Very turbulent flow 1. Increase dampening (see filter settings in "Flow
is erratic or 2. Sensor dirty Parameters" on p. 67)
fluctuating 3. Sensor broken 2. Clean sensor (Refer to Maintenance section, p.
4. Probe not mounted 112)
securely 3. Return flow meter to Fox Thermal for repair
5. Malfunction in flow (Refer to p. 136 for shipping instructions)
meter 4. Remount probe (see Installation section, p.
6. Meter installed 21); must be mounted securely without
incorrectly vibration. If vibration persists, choose a new
mounting location without vibration.
5. Return flow meter to Fox Thermal for repair
(Refer to p. 136 for shipping instructions)
6. Re-install meter according to instructions (Refer
to installation section, p. 21)

Troubleshooting | 116
 Model FT3
Troubleshooting

Problem Possible Cause(s) Action(s)

Display Error 1. Loose or damaged 1. Visual inspection.
ribbon cable 2. Return the meter or display for repair.
2. Damaged electronics
3. Ambient temperature 3. Operate meter between -20 to 70°C
Flow measure- 1. Probe not oriented 1. Orient probe per installation sections: Insertion
ment seems low properly (p. 25)
2. Sensor dirty 2. Clean sensor (p. 112)

Unit will not 1. No power input 1. Check for correct power supply voltage at TS1
power-up 2. Bad fuse on main board.
2. Check fuse (F1) located next to TS1 on main
board.

If fuse is OK and unit still won’t power up, call Fox

Thermal for additional assistance

Meter does not read Calibration table may be 1. Check the calibration table for a corrupted location.
up to full scale corrupted 2. Enter the password 9111.
3. From the Flow Parameters 2 menu screen, select
CAL (F1)
4. Select NXT (F1) to cycle through calibration table
to verify entries match the calibration certificate.
5. Check for CRC error code.

Troubleshooting | 117
Model FT3
Troubleshooting

Installation Problems
The following is a summary listing of problems that may be encountered with the installation of the
FT3 thermal mass flow meter.
1. Improper wiring connections.
Refer to Fig. 3.1 to 3.16 and "Wiring Precautions" in Wiring section (p. 33 to p. 49) for further
guidance.
2. Inadequate power source.
For FT3 models specified for 24VDC operation, the input voltage must be 24VDC ±10%. A
20 Watt power supply or greater is recommended for powering the FT3 to ensure it operates
properly under all temperature ventilation, and power on conditions. If the voltage supplied
at the input terminals of the FT3 is not within the range of 21.6VDC to 26.4VDC, a variety of
problems can occur including a dim display, inaccurate flow readings or faulty 4-20mA, pulse and
communication interface.
3. Flow measurement seems inaccurate.
• Check to ensure that the flow meter is installed so that the Flow Direction Indicator is pointing
in the direction of flow. Refer to Fig. 2.6 (p. 25). If not, change orientation of meter.
• Check that the insertion depth of the sensor/probe is correct. The end of the probe should be
adjusted as per Fig. 2.5 (p. 24).
• Ensure that there are a minimum of fifteen diameters of straight pipe upstream of the sensor
and ten diameters downstream. If complex flow disturbances are upstream of the sensor,
extension of the straight pipe may be required to ensure accurate flow measurement. Contact
Fox Thermal for assistance.
• Ensure that pipe inside diameter in the meter matches data on the Fox Thermal Calibration
Certificate. The pipe inside diameter is programmed into the flow meter through the front
panel (see Flow Parameters, p. 67).
4. Erratic flow reading (especially a flow reading spiking high).
This may be a symptom of moisture in the flow stream. Fox Thermal flow meters are designed
to work in relatively dry gas applications only. Contact Fox Thermal to discuss resolutions to this
problem.
5. Flow meter is not responding to flow.
• Check to ensure adequate power is supplied to the flow meter. If things appear to be correct,
perform this functional test before calling Fox Thermal. Carefully remove the probe and sensor
from the pipe. For those flow meters with a display - and if the display is reading zero - blow
on the sensor to see if a response occurs. If nothing happens, take a damp rag or sponge and
place it in contact with the sensor. A reading should occur. Contact Fox Thermal Customer
Service with this information.
6. Display and/or 4-20mA signal reading above zero flow when no flow is occurring in the pipe.
If the reading is less than 5% of full scale, it is likely this is a normal condition caused by
convection flow created by the heated sensor. It does not mean that the zero of the instrument is
improperly set. The Fox Thermal sensor is extremely sensitive to gas flow and can even read the
small flow caused by convection. If this is an unacceptable condition, please contact Fox Thermal
Customer Service for alternatives.
7. Mismatched serial numbers.
If you have more than one meter, you must ensure that the serial numbers of meter, remote, and/
or flow body match one another. These items have been manufactured and calibrated to operate
as a unit and cannot be mismatched.

Troubleshooting | 118
 Model FT3
Troubleshooting

Troubleshooting CAL-V™
If the FT3 meter fails a CAL-V™ Calibration Validation test, follow the steps below:

1. Flow rate in the pipe:

• Run the test again under a higher flow rate if possible.
2. The sensor may be dirty or damaged:
• Visually inspect the meter for damage. If damage is found, meter may need to be serviced.
Contact Fox Thermal Technical Assistance at 831-384-4300 for more information.
• Try cleaning the sensor and try the test again under higher gas flow conditions.
3. If the meter continues to fail, contact Fox Thermal Technical Assistance at 831-384-4300 for
more information.

Troubleshooting Zero CAL-CHECK™

If the FT3 Meter fails a Zero CAL-CHECK™ Calibration Validation test, there are a few reasons that
could be the cause:

1. The sensor may be dirty or damaged

• Visually inspect the meter for damage. If damage is found, meter may need to be serviced.
Contact Fox Thermal technical assistance at 831-384-4300 for more information
• Try cleaning the sensor and try the test again
• If the meter fails again, move to #2

2. The sensor may not be properly covered/isolated

• Out-of-pipe:
• Wind currents (fans in room included) could be affecting the sensor
• For best results, be sure to use the factory-supplied PVC sensor cover (see Fig. 4.5 on
Page 79)
• If the factory-supplied PVC sensor cover is unavailable, use a clean dry plastic beverage
bottle
• In Pipe:
• If using the retractor, be sure that the shut-off valve has been closed
• Make sure that there is a "no flow" or zero flow condition on the meter's sensor
• Try the test again
• If the meter fails again, move to #3

3. The meter may not have stabilized properly

• Make sure the meter is not being affected by vibrations or other movement
• Allow the meter to stabilize without being moved or touched for 15 minutes
• Try the test again
• If the meter continues to fail, contact Fox Thermal technical assistance at 831-384-4300

Troubleshooting | 119
Model FT3
Troubleshooting

Alarm Codes

Alarm
Reason Action
Code
13 Flow rate above Refer to the PARAMETER MENU 2 section on p. 67 of this Manual to
high limits verify limit is within range. Check ALM = HiFloAlm under PRM.
14 Flow rate below Refer to the PARAMETER MENU 2 section on p. 67 of this Manual to
low limits verify limit is within range. Check ALM = LoFloAlm under PRM.
15 Temperature Refer to the PARAMETER MENU 2 section on p. 67 of this Manual to
above high limits verify limit is within range. Check ALM=HiTempAlm under PRM.
16 Temperature Refer to the PARAMETER MENU 2 section on p. 67 of this Manual to
below low limits verify limit is within range. Check ALM = LoTempAlm
22 Sensor out of Refer to the ENGINEERING DISPLAY MENU on p. 16 of this Manual
range and the Fox Thermal factory Calibration Certificate to check CSV
voltage. Compare Display 10 value to Calibration Certificate CSV
voltage and verify it's within range.
23 Velocity out of Refer to the ENGINEERING DISPLAY MENU on p. 16 of this Manual
calibration table and the Fox Thermal factory Calibration Certificate to check CSV
range voltage. Compare Display 10 value to Calibration Certificate CSV
voltage and verify it's within range.
24 Check settings One or more internal settings are corrupted or out of spec. Contact Fox
Thermal Service for instructions to verify settings.
25 Simulation mode Meter is in Simulation Mode. Refer to the PARAMETER MENU 1 section
on p. 70 of this Manual. Use the SIM Section under Diagnostics to
return to normal operation.
26 Frequency output Refer to the DIGITAL OUTPUT MENU on p. 56 of this Manual. Verify
over range the Frequency Output settings are within limits.
32 4-20mA for flow Refer to the MAIN MENU on p. 54 of this Manual. Use the Set I/O
rate is out of section to verify range limits under FLO Set 4-20mA.
range
33 4-20mA for Refer to p. 54 of this Manual. Use the Set I/O section to verify
temperature is out range limits under FLO Set 4-20mA. Channel #2 can be set for flow or
of range temperature.
34 Busy Meter is recalculating new parameters.

35 Sensor Bridge The FT3 sensor readings are not correct. Check the sensor wiring to the
Shutdown FT3 electronic enclosure and remote enclosure..
36 Database CRC Refer to the PARAMETER MENU 2 section on p. 74 of this Manual to
Error reset CRC. Use SPC section of menu to reset CRC. Contact Fox Thermal
Service Department for possible causes.

Troubleshooting | 120
 Model FT3
Troubleshooting

Alarm Codes (cont'd)

Alarm
Reason Action
Code
37 Totalizer Error See "Reset the Total and Elapsed Time" on p. 74 for steps to clear
Detected Error Code. Contact Fox Thermal for possible causes.
38 CAL-V™ in Wait until the CAL-V™ or Cal Set is finished.
progress
39 ADC12 versus The tolerance between the 2 analog to digital converters is out of
ADC24 too far specification. Recalling manufacture default parameters using the
Restore Database command on p. 11 may correct the problem.
40 CAL-V™ Diff Fail The CAL-V™ Diff Failed. Check sensor wiring and verify that the
sensor's resistance is correct. Call Tech Support.
41 Zero CAL-CHECK™ Allow meter to stabilize for 15 minutes and perform the test again. If
Fail another "Fail" test results, call Tech Support.

Troubleshooting | 121
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Appendix

Performance Specs
Flow Accuracy:
±1% of reading ±0.2% of full scale
Accuracy specification applies to customer's selected flow range
Maximum range: 15 to 60,000 SFPM (0.07 to 280 NMPS)
Minimum range: 15 to 500 SFPM (0.07 to 2.4 NMPS)
Straight, unobstructed pipe requirement
Insertion Meters: 15 diameters upstream; 10 downstream
Inline Meters (1/2" size): 6" (152mm) upstream and downstream
Inline Meters (all other sizes): 8 diameters upstream; 4 downstream

Flow Repeatability: ±0.2% of full scale

Flow Response Time: 0.9 seconds (one time constant)
Temperature Accuracy: ±1.8° F (±1.0° C) -40 to 250º F (-40 to 121º C); 60 SFPM minimum
Calibration:
Factory Calibration to NIST traceable standards
CAL-V™ and Zero CAL-CHECK™: In situ, operator-initiated calibration validation

Operating Specs
Units of Measurement (field selectable):
SCFM, SCFH, NMPS, NM3/M, NM3/H, NM3/D, NLPS, NLPM, NLPH, SCFD, MSCFD, MMSCFD,
MMSCFM, SMPS, SM3/D, SM3/H, SM3/M, LB/S, LB/M, LB/H, LB/D, KG/S, KG/M, KG/H, SLPM, SFPM,
MT/H, MCFD

Gas Pressure (maximum at 100º F):

Insertion meter: 500 psig (34.5 barg)
316 SS inline meter with NPT ends: 500 psig (34.5 barg)
316 SS inline meter with 150 lb. flanges: 230 psig (15.86 barg)
Carbon steel inline meter with NPT ends: 500 psig (34.5 barg)
Carbon steel inline meter with 150 lb. flanges: 285 psig (19.65 barg)

Hot Tap/Retractor Assembly: 125 psig (8.62 barg)

NOTE! Check with factory for higher pressure options.
NOTE! When Teflon ferrule option ordered, gas pressure is 60 psig (4.1 barg) maximum
NOTE! The EU Pressure Equipment Directive (PED) requires that the minimum ambient and fluid
temperature rating for carbon steel flow bodies not be below -29°C.

Relative Humidity: 90% RH maximum; non-condensing

NOTE! Condensing liquids contacting the sensor can cause erratic flow indication.

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Operating Specs (cont'd)

Temperature:
ST sensor: -40 to 250°F (-40 to 121°C)
HT sensor: -40 to 650°F (-40 to 343°C)
Enclosure (without display or AC power supply): -40 to 158°F (-40 to 70°C)
Enclosure (with display and/or AC power supply): -4 to 158°F (-20 to 70°C)*
Remote Sensor Enclosure: -40 to 212ºF (-40 to 100°C)
*NOTE! Display dims below -4˚F (-20˚C), function returns once temperature rises again.

Flow Velocity Range:

15 to 60,000 SFPM (0.07 to 280 NMPS)
Turndown: up to 1000:1; 100:1 typical

Maximum Flow Ranges for Insertion Flow Meters

Pipe Diameter SCFM MSCFD NM3/hr
1.5" (40mm) 0-840 0-1,220 0-1,325
2" (50mm) 0-1,400 0-2,020 0-2,210
2.5" (63mm) 0-2,000 0-2,880 0-3,150
3" (80mm) 0-3,100 0-4,440 0-4,890
4" (100mm) 0-5,300 0-7,650 0-8,360
6" (150mm) 0-12,000 0-17,340 0-18,930
8" (200mm) 0-20,840 0-30,020 0-32,870
10" (250mm) 0-32,800 0-47,250 0-51,740
12" (300mm) 0-46,600 0-67,180 0-73,500

NOTE! To determine if the FT3 will operate accurately in other pipe sizes, divide the maximum flow rate by the pipe area.
The application is acceptable if the resulting velocity is within the velocity range above. Check Fox Thermal website for
velocity calculator.

Maximum Flow Ranges for Inline Flow Meters

Size SCFM MSCFD NM3/hr
0.5" 0-125 0-180 0-200
0.75" 0-220 0-320 0-350
1" 0-360 0-520 0-570
1.25" 0-625 0-900 0-990
1.5" 0-840 0-1,220 0-1,325
2" 0-1,400 0-2,020 0-2,210
2.5" 0-2,000 0-2,880 0-3,150
3" 0-3,100 0-4,440 0-4,890
4" 0-5,300 0-7,650 0-8,360
6" 0-12,000 0-17,340 0-18,930

NOTE! Standard conditions of air at 70°F and one atmosphere. Consult factory for other gases and for flow ranges above
those listed. Inline meters above 2,500 SCFM (7,900 NM3/H) air may require third party calibration. Contact Fox Thermal.

Appendix | 123
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Operating Specs (cont'd)

Input Power:
24VDC — ­­­­­– – – (±10%), 0.7 Amps (standard DC power)

100 to 240VAC (±10%/-15%), 50-60Hz, 0.2 Amps (with AC power option)

Note: Fluctuations of AC and DC power supply are not to exceed ±10% of rating.
Class I Equipment (Electrical Grounding Required for Safety).
Installation (Over-voltage) Category II for transient over-voltages.

Inputs/Outputs:
4-20mA Channel 1:
• Standard isolated 4-20mA output configured to indicate flow; fault indication per NAMUR
NE43.
4-20mA Channel 2:
• Standard isolated 4-20mA output configured to indicate either flow or temperature; fault
indication per NAMUR NE43.
Pulse/Alarm:
• Isolated open collector output rated for 5 to 24VDC, 20mA maximum load, 0 to 100Hz (the
pulse output can be configured to either transmit a 0 to 100Hz signal proportional to flow
rate or an on/off alarm).
Remote Switch Input:
• Can be configured to reset the flow totalizer and elapsed time.
Serial Communication
• Isolated Modbus RTU (RS485) option
• Isolated HART communication option
USB Communication:
• Isolated USB 2.0 for interfacing with a laptop or computer is standard.
• FT3 View™: A free PC-based software tool that provides complete configuration, remote
process monitoring, and data logging functions through USB communication.

4-20mA and Loop Verification:

Simulation mode used to align 4-20mA output with the input to customer’s PLC/DCS.

Physical Specs
Sensor material:
316 stainless steel, Hastelloy C276 optional

Enclosure:
NEMA 4X (IP67), aluminum, dual ¾” FNPT conduit entries. Cabling to remote enclosure: 5-conductor,
18 AWG, twisted, shielded, 100 feet maximum.

Flow Meter Installation:

Fox Thermal-supplied compression fitting connects to customer-supplied ¾” female branch outlet
welded to pipe.

Appendix | 124
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Agency Approvals
CE: Approved
EMC Directive; 2014/30/EU
Electrical Equipment for Measurement, Control and Lab Use: EN61326-1:2013
Low Voltage Directive (LVD): 2014/35/EU
Product Safety Testing: EN 61010-1: 2010
Pressure Equipment Directive: 2014/68/EU
Weld Testing: EN ISO 15614-1 and EN ISO 9606-1, ASME B31.3
FM and FMc: Approved
Class I, Division 1, Groups B,C,D;
Class II, Division 1, Groups E,F,G;
Class III, Division 1; T3C, Ta = - 40˚C to +70˚C;
Class 1, Zone 1, AEx/Ex d IIB + H2 (T6, T4, or T1*); Ta= -20˚C to +70˚C; Type 4X (IP67)
ATEX (FM12ATEX0034X): Approved
II 2 G Ex db IIB + H2 (T6, T4, or T1*) Gb Ta = - 20˚C to +70˚C; IP67
II 2 D Ex tb IIIC (T85˚C, T135˚C, or T450˚C*) Db Ta = - 20˚C to +70˚C; IP67
IECEx (IECEx FMG 12.0010X): Approved
Ex db IIB + H2 (T6, T4, or T1*) Gb Ta = - 20˚C to +70˚C; IP67
Ex tb IIIC (T85˚C or T135˚C*) Db Ta = - 20˚C to +70˚C; IP67**
ATEX and IECEx Standards:
EN 60079-0 EN 60079-31 IEC 60079-0 IEC 60079-31
EN 60079-1 EN 60529 +A1 IEC 60079-1 IEC 60529

Model Code Temp. Code Marking - Zones (Gas) Temp. Code Marking - Zones (Dust)
Enclosure Sensor Type Main Enclosure Remote Enclosure Main Enclosure Remote
Enclosure**
E1 ST T4 N/A 135°C N/A
E2 ST T4 N/A 135°C N/A
E3 ST T6 T4 85°C 135°C**
E4 ST T6 T4 85°C 135°C**
E3 HT T6 T1 85°C 450°C**
E4 HT T6 T1 85°C 450°C**

*Temperature code ratings for Zones are dependent on external process temperature factors and equipment enclosure
configuration. See the table above for specific temperature code ratings.
**The IECEx dust rating does not apply to the Remote Enclosure.

Specific Conditions of Use:

1. The flameproof joints of the equipment are not intended to be repaired. Consult the manufacturer
if dimensional information on the flameproof joints is necessary.
2. Refer to the manufacturer’s instructions to reduce the potential of an electrostatic charging hazard
on the equipment enclosure.

Appendix | 125
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Fig. 8.1: Insertion Meter with Retractor Dimensions

Dimensions shown in inches (millimeters).

8.1
(20.6)
4.6 3.9
(11.7) (9.9)

6.5
(16.5)

2X 3/4” NPT, FEMALE

10.75±.13
(27.3 ±.33)
“LL”

Table 8.1: Insertion Meter with 316 stainless steel probe

Probe Size Probe Size Dimension “LL” ± .10

[model code] [inches] [inches / millimeters]
15R 15" 15.0" (381mm)
18R 18" 18.0" (457mm)
24R 24" 24.0" (609mm)
30R 30" 30.0" (762mm)
36R 36" 36.0" (914mm)

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Appendix

Fig. 8.2: Remote Insertion Meter with Retractor Dimensions

CONDUIT, 3/4”, METAL

ø3.6
(ø9.1)
REMOTE CABLE, 5 CONDUCTOR, 4.4
SHIELDED, 100ft (30.48m) MAX (11.2)
8.1 2.0
(20.6) 4.6 (5.1)
3.9
(9.9) (11.7)

5.9
5.2 (15.0)
(13.2)

2X 3/4” NPT,
FEMALE

10.75±.13
(27.3 ±.33)
“LL”

Table 8.2: Remote Insertion Meter with Retractor

Probe Size Probe Size Dimension “LL” ± .10

[model code] [inches] [inches / millimeters]
15R 15" 15.0" (381mm)
18R 18" 18.0" (457mm)
24R 24" 24.0" (609mm)
30R 30" 30.0" (762mm)
36R 36" 36.0" (914mm)

Appendix | 127
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Appendix

Fig. 8.3: Remote Mounting Kit Dimensions

SIDE VIEW
BRACKET

2x U-BOLT
W/NUT JAM NUT
SEE ADAPTER
DETAIL

PROJECTIONS
ADAPTER
Ø2.38 4x
WASHER
2 IN. PIPE

THREADS
ADAPTER DETAIL

FT4X ENCLOSURE FRONT VIEW

F1 F2 F3 F4

4x Ø.344 2.81

2.81

MOUNTING
HOLE DETAIL

Appendix | 128
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Appendix

Fig. 8.4: Insertion Meter Dimensions

8.1
(20.6)
4.6
(11.7) 4.3
(10.9)

Input Signal
Power Wiring

2x 3/4 inch NPT Female

5.2 F1 F2 F3 F4

(13.2)

“HH”

“LL”

FLOW CL

Table 8.4: Insertion Meter with 316 stainless steel probe

Probe Size Probe Size Dimension “LL” ± .10 Dimension "HH" ± .10
[model code] [inches] [inches / millimeters] [inches / millimeters]
06IE 6" 6.0" (152mm) 12.9" (318mm)
09I 9" 9.0" (229mm) 15.5" (394mm)
12I 12" 12.0" (305mm) 18.5" (470mm)
15I 15" 15.0" (381mm) 21.5" (546mm)
18I 18" 18.0" (457mm) 24.5" (622mm)
24I 24" 24.0" (610mm) 30.5" (775mm)
30I 30" 30.0" (762mm) 36.5" (927mm)
36I 36" 36.0" (914mm) 42.5" (1080mm)

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Fig 8.5: Insertion Remote Meter Dimensions

3.6
(9.1)
4.4
(11.2)
2.0
4.6 (5.1)
(11.7)

Input
4.5
Power
(11.4)
2x 3/4 inch
5.2
NPT Female F1 F2 F3 F4
Remote Cable, 5 Conductor,
(13.2) Shielded, 100ft (30.48m) Max.
“HH”

“LL”

FLOW CL

Table 8.5: Insertion Remote Meter with 316 stainless steel probe

Probe Size Probe Size Dimension “LL” ± .10 Dimension “HH” ± .10
[model code] [inches] [inches / millimeters] [inches / millimeters]
06IE 6" 6.0" (152mm) 11.9" (302mm)
09I 9" 9.0" (229mm) 14.9" (379mm)
12I 12" 12.0" (305mm) 17.9" (455mm)
15I 15" 15.0" (381mm) 20.9" (531mm)
18I 18" 18.0" (457mm) 23.9" (607mm)
24I 24" 24.0" (610mm) 29.9" (760mm)
30I 30" 30.0" (762mm) 35.9" (912mm)
36I 36" 36.0" (914mm) 41.9" (1064mm)

Appendix | 130
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Fig. 8.6: Inline Meter with Flow Body and NPT End Connections Dimensions

8.1
(20.6)
4.6
(11.7) 4.3
(10.9)

Input Signal
Power Wiring

2x 3/4 inch NPT Female

F1 F2 F3 F4 5.2
(13.2)

“H”

2x NPT Male Thread

CL

“L”

Table 8.6: Inline Meter with Flow Body and NPT End Connections

Body Size Body Size Dimension “L” ± .10 Dimension “H” ± .10
[model code] [inches] [inches] [inches / millimeters]
05P * 0.50" 12" 10.5" (267mm)
075P * 0.75" 12" 10.5" (267mm)
10P * 1.00" 12" 10.5" (267mm)
125P * 1.25" 12" 10.5" (267mm)
15P * 1.50" 12" 10.5" (267mm)
20P ** 2.00" 12" 10.5" (267mm)
25P ** 2.25" 18" 10.6" (269mm)
30P ** 3.00" 18" 12.5" (318mm)

*Available in 316 stainless steel only.

**Available in 316 stainless steel or A106 Grade B Carbon steel pipe.

Appendix | 131
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Fig 8.7: Inline Remote Meter with Flow Body and NPT End Connections Dimensions

3.6
(9.1)
4.4
(11.2)
2.0
4.6 (5.1)
(11.7)

Input
4.5
Power
(11.4)

5.2 F1 F2 F3 F4 Remote Cable, 5 Conductor,

(13.2) Shielded, 100FT Max.
“HH”

2x NPT Male Thread

CL

“L”

Table 8.7: Inline Remote Meter with Flow Body and NPT End Connections

Body Size Body Size Dimension “L” ± .10 Dimension “HH” ± .10
[model code] [inches] [inches] [inches / millimeters]
05P * 0.50" 12" 10.5" (267mm)
075P * 0.75" 12" 10.5" (267mm)
10P * 1.00" 12" 10.5" (267mm)
125P * 1.25" 12" 10.5" (267mm)
15P * 1.50" 12" 10.5" (267mm)
20P ** 2.00" 12" 10.5" (267mm)
25P ** 2.50" 18" 10.6" (269mm)
30P ** 3.00" 18" 12.5" (318mm)

*Available in 316 stainless steel only.

**Available in 316 stainless steel or A106 Grade B Carbon steel pipe.

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Fig. 8.8: Inline Meter with Flow Body and 150 lb. RF Flange End Connections Dimensions

8.1
(20.6)

4.3
4.6
(11.7) (10.9)

2x 3/4 inch NPT Female

F1 F2 F3 F4 5.2
(13.2)

“H”

CL

“L”

2X Flange, Raised Face, ANSI B16.5, 316 SST

Table 8.8: Inline Meter with Flow Body and 150 lb. RF Flange End Connections Dimensions

Body Size Body Size Dimension “L” ± .10 Dimension “H” ± .10
[model code] [inches] [inches] [inches / millimeters]
05F * 0.50" 12" 10.5" (267mm)
075F * 0.75" 12" 10.5" (267mm)
10F * 1.00" 12" 10.5" (267mm)
125F * 1.25" 12" 10.5" (267mm)
15F * 1.50" 12" 10.5" (267mm)
20F ** 2.00" 12" 10.5" (267mm)
25F ** 2.50" 18" 10.6" (269mm)
30F ** 3.00" 18" 12.5" (318mm)
40F ** 4.00" 18" 12.5" (318mm)
60F ** 6.00" 24" 12.5" (318mm)

*Available in 316 stainless steel only.

**Available in 316 stainless steel or A106 Grade B Carbon steel pipe.

Appendix | 133
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Appendix

Fig 8.9: Inline Remote Meter with Flow Body and 150 lb. RF Flange End Connections Dimensions

3.6
(9.1)
4.4
(11.2)
2.0
(5.1)
4.6
(11.7)

4.5
2X 3/4 " NPT,
(11.4)
Female
5.2
Remote Cable, 5 Conductor,
F1 F2 F3 F4

(13.2)
Shielded, 100FT Max.
“HH”

CL

“L”

Table 8.9: Inline Remote Meter with Flow Body and 150 lb. RF Flange End Connections Dimensions

Body Size Body Size Dimension “L” ± .10 Dimension “HH” ± .10
[model code] [inches] [inches] [inches / millimeters]
05F * 0.50" 12" 10.5" (267mm)
075F * 0.75" 12" 10.5" (267mm)
10F * 1.00" 12" 10.5" (267mm)
125F * 1.25" 12" 10.5" (267mm)
15F * 1.50" 12" 10.5" (267mm)
20F ** 2.00" 12" 10.5" (267mm)
25F ** 2.50" 18" 10.6" (269mm)
30F ** 3.00" 18" 12.5" (318mm)
40F ** 4.00" 18" 12.5" (318mm)
60F ** 6.00" 24" 12.5" (318mm)

*Available in 316 stainless steel only.

**Available in 316 stainless steel or A106 Grade B Carbon steel pipe.

Appendix | 134
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Warranty Statement and Terms and Conditions

Limited Warranty - All Products

Fox Thermal warrants that for a period of one year following the date of original shipment of Fox’s
products that the product will conform to Fox’s standard written specifications applicable to such
product and will be free from defects in workmanship. For more details, view the Limited Warranty
section in the Terms and Conditions of Sale. Find that document at this link:

https://www.foxthermal.com/pdf/terms-and-conditions.pdf

Consumable and Fragile Material Warranty

Fox warrants that consumable materials, supplied by Fox either as part of an instrument or system, or
separately, will be free from defects in material and workmanship at the time of shipment. A list of key
consumables and expected lifetimes may be found in the applicable Seller equipment operation and
maintenance manual.

Terms and Conditions of Sale

For more details about Fox’s warranty statement and exclusions, please download the Terms and
Conditions of Sale document. Find that document at this link:

https://www.foxthermal.com/pdf/terms-and-conditions.pdf

Appendix | 135
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Returning Your Meter

The Fox Thermal Customer Service Department
(PH: 831-384-4300 or service@foxthermal.com) can help you through the process of returning a
meter for service.

If it becomes necessary to return a Fox Thermal flow meter for service or recalibration, please follow
these steps:

1. A Return Material Authorization (RMA) Number must be obtained from the Fox Thermal Customer
Service Department prior to returning any Fox Thermal meter(s).
2. Please have your meter’s serial number(s) available.
3. Read and complete the Fox Thermal RMA Customer Information Form. Be sure to initial the
decontamination statement as well as provide complete return shipping instructions (we cannot
deliver to post office boxes).
4. The entire flow meter must be returned, including all electronics (unless specifically instructed
to do otherwise). ALL serial numbers must match their corresponding meters. This is especially
necessary when returning flow body models.
5. Clean and decontaminate all wetted parts before returning to Fox Thermal.
6. Ship the meter to the following address:
Fox Thermal Instruments, Inc.
399 Reservation Road
Marina, CA 93933
Attn: Service Dept.
[RMA Number]

NOTE! Be sure to review all of the information on the Customer Information Form before
sending your meter to the Fox Thermal Customer Service Department. The Fox Thermal
Shipping/Receiving Department cannot accept meters that have not been prepared
appropriately.

What to expect while your meter is being serviced

Depending on the type of service required when returning your Fox Thermal meter, there are varying
turnover times for servicing a meter. The average time needed to service the meter is 7-10 days (not
including shipping or peak production times).

If you have already shipped your meter to Fox Thermal for servicing and would like to check the
status of your meter, please fill out our online Service Order Status form located at www.foxthermal.
com and you will hear from a Customer Service Rep within 1 business day of your requested update.

Rush recalibration service is available for a fee. Restrictions apply.

Appendix | 136
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Glossary of Terms and Definitions

AWG American Wire Gauge NL Normal Liter

Bara Bar absolute NLPH Normal Liter per Hour
CTC Contact NLPM Normal Liter per Minute
CAL Calibration NM3 Normal cubic Meter
CHG Change NM3/H Normal cubic Meter per Hour
COM Communication NM3/M Normal cubic Meter per Minute
CSV Current Sense Voltage NPT National Pipe Thread
DC Direct Current PC Personal Computer
DCS Distributed Control System P/U Pulse per Unit
DN Down PIP A^2 Pipe Area
DSP Display PLC Programmable Logic
ELP Elapsed time Controller
Feq Frequency PRM Parameters
Ft^2 Square Feet PRS Pressure
I/O Input/Output PSIA Pounds per Square Inch
INP Input Absolute
LB Pound Pt Point
LB/D Pound per Day PSW Password
LB/H Pound per Hour SIM Simulation
LB/M Pound per Minute SCF Standard Cubic Feet
LB/S Pound per Second SCFM Standard Cubic Feet per
LCD Liquid Crystal Display Minute
KG Kilogram SCFH Standard Cubic Feet per Hour
KG/H Kilogram per Hour SCFD Standard Cubic Feet per Day
KG/M Kilogram per Minute SPC Special Control
KG/S Kilogram per Second STP Standard Temperature and
M^2 Square Meter Pressure
mmHG Pressure in millimeters of mercury TMP Temperature
MMSCFD Million Standard Cubic Feet per TSI Internal Variable
Day TSV Internal Variable
MXFLO Maximum Flow UNT Unit
NEMA National Electrical Manufactures U/P Unit per Pulse
Association 420 4-20mA output
NIST National Institute of Standards
and Technology

Appendix | 137
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Index

Access to Electronics, p. 33 Preventative Maintenance, p. 112

Alarm Codes, p. 120 Product Description, p. 17
Alarm wiring, p. 40 Programming
Analog 4-20mA output, p. 54 Analog 4-20mA Output, p. 54
Breakage or Damage of Probe, p. 113 Alarm Output, p. 58
Calibration Validation, p. 122 Changing values or strings, p. 53
Dimension Details, p. 126 Display Setup, p. 63
Display Screens, p. 51 Flow Parameters, p. 67
Display Setup, p. 63 Flow and maximum pulse/alarm, p. 57
Entering the programming mode, p. 53 Pulse Output, p. 56
Filter value, p. 53 Password, p. 64
Flow Meter Placement, p. 21 Programming Mode, p. 53
Flow Units, p. 64 Pulse-per-unit, p. 57
Pulse Output, p. 56 Reset CRC, p. 74
Fuse Replacement, p. 112 Selecting from a list, p. 53
Glossary, p. 137 Serial Communication, p. 59
Installation, Simulation, p. 74
Compression Fitting - Insertion, p. 33 Unit-per-pulse, p. 57
Lateral Placement, p. 21 Unit settings, p. 64
Mounting, p. 21 Using the Local Display, p. 53
Orientation of Meter - Insertion, p. 25 Replacements Fuses, p. 112
Introduction, p. 17 Return Procedure, p. 136
Level 2 password, p. 64 Sensor Cleaning, p. 112
Local Display, p. 19 Sensor Orientation, p. 25
Local Input Wiring, p. 33 Simulation Mode, p. 74
Mass Flow, p. 17 Theory of Operation, p. 17
Measurement Mode, p. 51 To program the display, p. 63
Menu Tree, Troubleshooting
Digital Output, p. 9 Alarm Codes, p. 120
Display Menu, p. 12 General, p. 116
Engineering Display, p. 13 Installation Problems, p. 118
Main Menu, p. 8 USB Interface, p. 50
Flow Menu 1, p. 10 Warranty, p. 135
Flow Menu 2, p. 11 Wiring
Calibration Validation Menu, p. 13 Pulse/Alarm Outputs, p. 41
Mounting meter, p. 21 Grounding, p. 34
Orientation of meter - Insertion type, p. 25 Input - Local, p. 33
Password Instructions, p. 33
Level 1, p. 64 Local meters, p. 33
Level 2, p. 64 Power Input, p. 36
Programming, p. 64 Precautions, p. 33
Power Input Wiring, p. 36

Appendix | 138
Appendix | 139
 Wiring Definition of Terms

NOTE! is used for Notes and

Troubleshooting Tips Information

WARNING! is used to indicate a hazardous situation which, if not avoided, could

result in death or serious injury.

CAUTION! is used to indicate a hazardous situation which, if not avoided, could

result in minor or moderate injury.

Indicates compliance with the WEEE Directive. Please dispose of the product in
accordance with local regulations and conventions.

Indicates compliance with the applicable European Union Directives for Safety LVD
(Low Voltage Directive), EMC (Electromagnetic Compatibility Directive), and PED
(Pressure Equipment Directive).

IP67 Enclosure Protection Classification per IEC 60529: Protected against the ingress of
dust and Immersion.

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