BACnet MS/TP Interface

© 2020 Daikin North America, LLC

Features
▪ Direct connection to the BMS using BACnet MS/TP protocol
▪ BTL Certified device
▪ Easy commissioning using DIP switches & BACnet Objects.
▪ Each adaptor can connect to 4 outdoor units and 32 indoor
units.
▪ BACnet virtual router function implemented: Individual BACnet
device ID assigned to each indoor unit group address and
outdoor unit Airnet address.
▪ Independent heating and cooling setpoints.
▪ Can be mounted to indoor unit or outdoor units (Select models
only)
▪ BACnet objects for operation data (compatible outdoor units
and indoor unit data).
▪ Supports Celsius or Fahrenheit for temperature values.
DTA118A71/72
▪ Independent BACnet object error status for indoor unit and
outdoor unit.

© 2020 Daikin North America, LLC 2

Specifications
Model DTA118A71/72

Maximum Connections 32 Indoor Units / 4 Outdoor Units

BMS
18AWG-2, No polarity
Communication Wire (DIII-Net)
Stranded, Non-shielded

Communication Wire (BACnet) 16-18 AWG, polarity senstive

MS/TP
Total Wiring Length (BACnet) 1,640ft. (500 m)

Communication Protocol BACnet MS/TP / DIII-Net

Communication Speed
9600/19200/28400/38400 bps
(BACnet)

BACnet MS/TP Address range 0 - 127

DTA118A71/72
Number of BACnet devices on
32
the BACnet MSTP Network
DIII-NET
Indoor unit DIII-Net address
(1-00 to 2-15) or (3-00 to 4-15)
range

16VDC supplied by Outdoor Unit*

Power
(1.58VA maximum)

Operating Temp Range -4 to 149oF (-20 to 65oC)

95% or less (RH)

Operating Humidity Range
(w/o condensation)

Dimensions (WxHxD) 3.94 x 3.94 inch (100 x 100 mm)

Weight (Mass) 0.18 lbs. (80 g)

© 2020 Daikin North America, LLC 3

System Overview

Max 32 IDU
BMS DTA118A71/72
& 4 ODU

MS/TP
DTA118A71/72
Max 32 IDU
MAX 2 Adaptor & 4 ODU
per DIII-net

• The total wiring length of the BACnet MS/TP Communication wire must be within 1640ft.
• A maximum of 32 indoor units and 4 outdoor units can be controlled and monitored using the adaptor.
• A maximum of 2 adaptors can be connected to one DIII-NET network.
• A maximum of 32 devices can be connected to the same BACnet MS/TP network as the adaptor.
© 2020 Daikin North America, LLC 4
Virtual BACnet Router
▪ Adaptor Operates as a BACnet Client (max. 1 machine)
BACnet network
(BACnet network number = α
BACnet router/gateway.
▪ The Indoor unit device BACnet MS/TP

operates as One indoor

unit virtual BACnet BACnet Router/Gateway

device. (one indoor unit

(DIII-NET, max. 1 ports One Virtual BACnet Network
management point) Max. 32 IDU & 4 IDU) (BACnet network number = β

▪ The Outdoor Unit

device operates as a System Control Device
one virtual BACnet (Virtual BACnet Device)

Device Instance No = A
device.
BACnet Address = Device Instance No = W Device Instance No = X Device Instance No = Y Device Instance No = Z
(NetNumber = β,
▪ The VRV MAC Address = A’) BACnet Address = BACnet Address = BACnet Address = BACnet Address =
(NetNumber = β, (NetNumber = β, (NetNumber = β, (NetNumber = β,
communication line (DIII ObjectList
Setting items for
MAC Address = W’) MAC Address = X’) MAC Address = Y’) MAC Address = Z’)

network) is handled as controls on the iTM ObjectList

Monitoring setting items
ObjectList
Monitoring setting items
ObjectList
Monitoring setting items
ObjectList
Monitoring setting items
one virtual BACnet for one device for one device for one device for one device

network. DIII-NET
Virtual BACnet Network Outdoor Unit Device* Indoor Unit Device*
(Virtual BACnet device) (Virtual BACnet device)

© 2020 Daikin North America, LLC 5

Hardware Configuration
16VDC POWER
CONNECTOR from
IDU or ODU

H3P, H4P MS/TP

COMMUNICATION
H1P, H2P DIII-NET STATUS LED
STATUS LED

DIII-NET
COMMUNICATION
DIP SWITCHES

TERMINAL
RESISTANCE

MS/TP
COMMUNICATION
Service Monitor LED
(flashes Green during CPU
Normal Operation)
© 2020 Daikin North America, LLC 6
Installation
1

Outdoor unit Model Mounting

1 Power Supply Connect between the (X1A) connector on the adaptor and the
wiring (X37A) connector on the outdoor unit PCB. RXYQ72_XA or T(A), The adaptor cannot be mounted inside the outdoor unit.
REYQ72_XA or T(A),
2 DIII-NET Connect between the (X7A) connector on the adaptor and the F1-F2 RWE**, RXTQ**, RXSQ**
Communication (TO OUT/D UNIT) terminal of the outdoor unit.
REYQ_AA/RXYQ_AA The adaptor can be mounted inside the E-box of the outdoor
wiring
unit.
3 BACnet MS/TP • Connect between this adaptor BACnet MS/TP Communication
REYQ_XA/RXYQ_XA The adaptor can be mounted inside the E-box of the outdoor unit
Communication Terminal(X2M) and Building Management System Terminal.
using the BKS26A-US mounting plate.
wire(RS-485) • Connect between this adaptor A[+] connector and Building
(Field provided) Management System Terminal [+]connector, B[-]connector and REYQ_T(A)/RXYQ_T(A) The adaptor can be mounted inside the E-box of the outdoor unit
Building Management System [-] connector. using the BKS26A-US mounting plate.
• If shielded wire is used for the BACnet MS/TP communication.
• Do not ground with outdoor unit earth. RELQ_TA/RXLQ_TA The adaptor can be mounted inside the E-box of the outdoor unit
using the BKS26A-US mounting plate.

© 2020 Daikin North America, LLC 7

Wiring & Installation

16 VDC power supply (some units may require an 16VDC

VRV
external mounting box*) (X37A plug)

RXTQ36/48TAVJU No

RXTQ60TAVJU Yes

REYQ72/96/120/144/168TYDN Yes
DIII-Net
communication REYQ72/96/120/144/168TTJU Yes

RXYQ72/96/120/144/168TYDN Yes

RXYQ72/96/120/144/168TTJU Yes
*For mounting instructions refer to the Adapter installation manual.

BACnet MSTP communication If an outdoor unit does not have the 16VDC power supply, a
separate 16 VDC power supply must be provided, and the
Polarity sensitive
Maximum wiring length 1640ft (500m)
Adapter can be placed anywhere on the F1-F2 out circuit.
16 AWG – 18 AWG wiring The 16VDC power can also used from the indoor unit
X18A/X35A plug.

© 2020 Daikin North America, LLC 8

Indoor unit Points List
Indoor unit points list (Note 1)
Unit On_Off Status Filter sign Reset Notes:
1. Refer to design guide & submittal datasheet for the indoor unit point
Unit On/Off Command Indoor Unit Status combability.
Alarm Status Communication Status 2. The Mini-Splits have varied setpoints ranges (64F – 90F in cooling and
50F – 86F in heating). In the event a value outside of the available
Operation Mode (Note 3,4) Thermo On status setpoint range is sent from the BACnet building management system via
BACnet Adaptor , the indoor unit will ignore the out-of-range setpoint
Ventilation Mode Compressor Status command (However, in the above case, BACnet Adaptor can send cooling
Ventilation Rate Aux Heater Status setpoint value and Heating setpoint value of Only 64F-82F.)
3. Only Ventilation mode on VAM.
Fresh Up Forced Thermo Off 4. Fan, Dry, and Auto are not supported connected using KRP928 board.
5. Unit types other than those supported display an invalid value (0)
Room Temperature Indoor unit changeover option 6. The data is invalid for models that do not support the target data.
Cooling Setpoint (Note 2) Return air temperature (Note 6,7) 7. For FXDQ, FXHQ, FHQ these can not be displayed.

Heating Setpoint (Note 2) Discharge air temperature (Note 5,7)

Fan Speed Liquid pipe temperature (Note 6,7)
Airflow Direction Gas pipe temperature (Note 6,7)
Remote Controller Prohibit (On_Off) EV position (Note 6,7)
Remote Controller Prohibit OU airnet address (Note 6,7)
(Operation Mode)
Remote Controller Prohibit (On_Off) Forced Stop status
Filter Sign Status Energy saving command (Setpoint
shift)
© 2020 Daikin North America, LLC 9
Outdoor unit Points List
General ODU Points ODU Points for each condensing unit (Master/ Sub1, Sub2)
Communication Status M_Condensing Pressure M_Liquid Pipe Temperature (HX Lower)
Operation Mode M_Evaporating Pressure M_Liquid Pipe Temperature (Deicer)
Outdoor unit Alarm Status M_Condensing Temperature M_Gas Pipe Temperature (HX Upper
Special Modes1 M_Evaporating Temperature Suction Temperature
Electric Power M_Inverter Compressor 1 Speed Compressor Suction Temperature
Electric Current M_Inverter Compressor 2 Speed Subcool Inlet Temperature
Outdoor Air Temperature M_Fan Step Subcool Outlet Temperature
M_EV Position 1 Compressor Body Temperature
Backup Operation
M_EV Position 2 Receiver Inlet Temperature,
Stepdown control
M_Hot Gas Temperature (Compressor 1) Subcool EV Position,

1Specials
M_Hot Gas Temperature (Compressor 2) 4WayValve
Modes
1. Defrost
2: Oil Return M_Liquid Pipe Temperature Compressor1 current,
3: Pump-down operation
4: Restart Standby M_Sub Compressor Body Temperature Compressor2 current,
5: Off
2Stepdown control M_Liquid Pipe Temperature (HX Upper)
1. Outdoor unit 1 (main) stepdown control is active
2: Outdoor unit 2 (sub 1) stepdown control is active
3: Outdoor unit 3 (sub 2) stepdown control is active
4: Main & sub 1 stepdown control is active
5: Main & sub 2 stepdown control is active
6: Sub 1 & sub 2 stepdown control is active
7: Main & sub 1 & sub 2 stepdown control is active
8: All Off
© 2020 Daikin North America, LLC 10
BACnet MS/TP Network speed
Baud Rate Selection
▪ The Network Speed should be provided by the BMS integrator.
▪ Every BACnet MS/TP adaptor should have the same speed
▪ The Baud rate is assigned using DS1-1

Item OFF ON
DS1-1 Baud Rate selection Auto Detect Manual
Factory Default

▪ If the DS1-1 is set to ON, The Manual settings of the Baud rate can be
set from the BMS
▪ Change the “Present Value” of instance number 7 as following:

Present Value BAUD RATE

1 9600bps
2 19200bps
3 38400bps

© 2020 Daikin North America, LLC 11

Adaptor MAC Address
MAC Address for each BACnet MS/TP Adaptor
▪ The MAC addresses should be provided by the BMS integrator.
▪ Every BACnet MS/TP adaptor should have a unique MAC address
in the BACnet MS/TP Network.
▪ The MAC address is assigned using DS1-2,3,4 & DS2-1,2,3,4
which represent the address on a binary format
64-32-16—8-4-2-1
Address: 0 (Factory Default)

2 3 4 1 2 3 4
DS1 DS2

The Black box represent

the dip switch position

© 2020 Daikin North America, LLC 12

BACnet MS/TP Terminal Resistance
▪ Terminal resistance is added to the last the device in a BACnet communication network to prevent reflections.
▪ The Terminal resistance value should be provided by the BMS integrator.

SS1 SS2 SS3

SS1 is not used

Don’t change

No Resistance 100 Ohm

(Factory Default)
120 Ohm
© 2020 Daikin North America, LLC 13
BACnet MS/TP Adaptor Settings
Instance Point Name Description
No.
1 Set Scale 0: Fahrenheit (Default)
1: Celsius
2 D3 control Group 1: None (Default) MS/TP
address Indoor 2: Group Addresses 1-00 to 2-15
3: Group addresses 3-00 to 4-15
3 D3 control Airnet 1: None (Default)
address Outdoor 2: Airnet Addresses 1 to 4
3: Airnet Addresses 5 to 8
BMS
4: Airnet Addresses 9 to 12 DTA118A71/72
5: Airnet Addresses 13 to16
(17 states, up to Airnet address 64)
4 Device Instance method 0: Self (default)
(for Virtual devices) 1: BMS

5 Adaptor Device Instance 0 (default)

Sets the BACnet device instance

6 Network Number 153 (default)

Sets the BACnet network number for the virtual BACnet
Network. Must be a unique Network number

7 Baud Rate 1: 9600 (Default)

2: 19200
3: 38400

Power Reset the Adaptor after changing the settings from the BMS or a BACnet explorer software

© 2020 Daikin North America, LLC 14

Addressing Schemes
BMS Specified Based on MAC address

▪ The instance numbers are sequentially ▪ The instance number is assigned based on
assigned based on the adaptor instance adaptor’s MAC address.
number.
▪ For example
▪ Adaptor instance number is 100.
▪ The indoor unit instance numbers shall be 101
53 0 207
to 132 based on group address
IDU: 100 -> group address 1-00
▪ The outdoor unit instance numbers shall be 133 ODU: 001 -> Airnet address 1
ADP: 000
to 136 based on outdoor unit Airnet address.
0=IDU, 1=ODU,
15
2=ADP
MAC address 001
to 127

Examples
© 2020 Daikin North America, LLC 15
531002, 532000
LED Indication

H1P H2P H3P H4P H5P H6P H7P

LED Description
H1P Transmission of DIII-Net message
H2P Receiving DIII-Net message
H3P Transmission of BACnet message
H4P Receiving BACnet message
H5P Not Used
H6P Not Used
H7P Not Used

© 2020 Daikin North America, LLC 16

Exercise 1: BACnet MS/TP Setup Activity

Place Checkmark in
each box as you
❑ 1. With power off, connect the DTA118A72 MS/TP board to the ODU demo
complete each step
❑ 2. Set the Dip switches for the desired baud rate input and MAC address
❑ 3. Plug the supplied USB to BACnet MS/TP adaptor into your computer and verify drivers
❑ 4. Open up Device Manager to verify the assigned Comm Port number
❑ 5. Connect the supplied 2 pair shielded cable from the adaptor to the DTA118 (Pin 1 + Pin 2 – to A + and B –)
❑ 6. Power up the ODU demo board (IDU board should have already been powered from previous exercise)
❑ 7. Open up YABE from your computer and click on the Add Device icon
❑ 8. Select the Port # drop down arrow under the BACnet / MSTP over serial section
❑ 8 a. Select the Baud rate of 9600 for the initial connection then click ADD
❑ 8 b. The first time you will be prompted to select a valid source address
❑ 8 c. You should now see the Device address and the units connected beneath it with their virtual addresses already assigned
❑ 8 d. You should now see 7 sections as discussed under the MS/TP adaptor settings slide
❑ 8 e. Change the baud rate speed to 38,400.
❑ 8 f. What instance # is selected to change this option?
❑ 9. Remember that the outdoor may not show up initially when YABE is launched
❑ 9 a. If it does not show up, can anyone tell me why?

© 2020 Daikin North America, LLC 17

Exercise 2: BACnet MS/TP Control Activity

Place Checkmark in
each box as you
❑ 1. Click on any of the visible Indoor units within the YABE program complete each step
❑ 2. Find the On/Off command
❑2 a. What Binary Value is it?
❑2 b. What present value do you see under the property section?
❑ 3. Change the value as discussed earlier
❑3 a. What options do we have to choose from?
❑ 4. Press the enter button when the value has changed
❑ 4 a. What happened?
❑ 5. Change the value back

❑OPEN DISCUSSION

© 2020 Daikin North America, LLC 18

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