s 8 174

TX-I/O™

Super universal modules TXM1.8X

TXM1.8X-ML
• Two fully compatible versions:
– TXM1.8X: 8 inputs/outputs with LED signal / fault indication
– TXM1.8X-ML: As TXM1.8X, but with additional local override facility
with LCD display (LO/ID to ISO 16 484-2)
• 8 universal I/O points, individually configurable as
– Digital input: maintained contact, pulse or counter
– Analog input: sensor, 0..10V, 4..20mA
– Analog output: 0..10V, 4..20mA (I/O points 5 ... 8)
• Compact DIN format, small footprint
• Separate terminal base and plug-in I/O module for convenient handling
– Self-establishing bus connection for maximum ease of installation
– Terminal isolation function for fast commissioning
– I/O module replaceable in seconds, without rewiring and without affecting
the full functioning of the remaining I/O modules
• All terminals are directly on the I/O modules, allowing direct connection of
field devices without additional terminal strips.
• Simple strategy for operation and display
– I/O status LED for each I/O point; mode of operation (N/C or N/O) and
brightness depend on I/O function
– LEDs and LCD for fast diagnostics
• Double-sided labels for identification of all I/O points

CM2N8174en_12
2019-09-01 Building Technologies
Functions

The modules support the following I/O functions:

Function Signal type (TRA) Signal type Description
Status signal BI NO D20 Volt-free, interrogation (maintained contact), N/O contact
BI NC D20R Volt-free, interrogation (maintained contact), N/C contact
Status pulses BI Pulse NO D20S Volt-free, interrogation (pulse), N/O, N/C contact
BI Pulse NC
Counter Volt-free, N/O contact, interrogation (pulse)
pulses CI El (100Hz) C Counting frequency max. 100 Hz (electronic counter)
CI Mech (10/25Hz) max. 25 Hz (mech. counter)
Voltage, AI 0-10V U10 DC voltage 0 ... 10 V
current,
AI 4-20mA I420 DC current 4 ... 20 mA
resistance and
temperature AI 0-20mA I25 DC current 0 ... 20 mA
Please note that the max. current is 20 mA!

AI 2500 Ohm R2K5 Resistance 2500 Ω

AI Ni1000 extended Ni1K Temperature sensor LG-Ni 1000 ohms, up to 180 °C

AI Ni1000 R1K Temperature sensor LG-Ni 1000 ohms

AI PT1K375 Pt1K 375 Temperature sensor Pt 1000 (USA)

AI PT1K385 Pt1K 385 Temperature sensor Pt 1000 (Europe)

AI Pt1000 P1K Resistance Pt 1000 ohms and resistance transmitter

AI T1 (PTC) T1 Temperature sensor PTC

AI NTC10K NTC10 K Temperature sensor NTC 10 K

AI NTC100K NTC100 K Temperature sensor NTC 100 K

Proportional AO 0-10V Y10S Proportional control output, DC 0 ... 10 V, with storage of

output signals control value

AO 4-20mA Y420 Proportional control output, current DC 4 ... 20 mA (I/O

points 5 … 8 only)

For a detailed description of these functions, please refer to document CA110561,

"TX-I/O™ functions and operation".

Compatibility

Support of signal types and functions in different building automation and control
systems: see TX-I/O Engineering and installation manual, CM110562

Type summary

ASN Super universal module TXM1.8X

Super universal module TXM1.8X-ML with LCD display and local override

Delivery The terminal base and the electronic plug-in unit are interconnected and delivered in
the same box.

Accessories The available accessories include address keys, label sheets, and spare transparent
label holders. Refer to data sheet CM2N8170.

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Technical and mechanical design

For a description of the features common to all TX-I/O™ modules, please refer to the
TX-I/O™ Engineering and installation manual, document CM110562.

Indicators and operator controls

Connection terminals (No. 1 screwdriver for slotted or recessed-

head * screws)
with test pickup (for 1.8...2 mm pins) and terminal number
Signal designation

Override status LEDs (yellow)

Address key and module status LED

LCD panel (TXM1.8X-ML only)

I/O point numbers

Override button (TXM18X-ML only)

I/O status LEDs (green)

* Combined slotted / recessed-head screws from mid-2012

I/O status LEDs • The I/O status LEDs (green) indicate the status of the inputs and outputs (peripheral
devices)
• They are also used for diagnostics

Module status LED • The module status LED illuminates the transparent address key
• The LED (green) shows the module status as a whole (as opposed to the status of
the I/O points)
• It is also used for diagnostics

Address key • The module operates only with the address key inserted
• The module address is mechanically encoded in the address key
• When replacing the I/O module, the address key must be swiveled outward. It
remains plugged into in the terminal base.

Local override and LCD display (TXM1.8X-ML only)

For a detailed description, please refer to document CM110561, "TX-I/O™ Functions

and operation".

Override button • Pressing an button in the middle enables or disables the local override
• Pressing "+" or "–" respectively increases or reduces the output value.
• Only outputs can be overwritten. Any attempt to overwrite an input results in an error
indication.

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Override status LED • The yellow "Override" LED indicates that local override is active

LCD display • The following information is displayed for each I/O point:
– Configured signal type
– Symbolic display of process value
– Information for diagnostics.
• All safety-relevant functions must be implemented with external solutions
Warning • The local override must not be used for safety shutdown operations
• In compliance with the standard (ISO 16 484-2, Section 3.110), the module
executes all local overrides directly, without safety precautions or interlocks.
 Full responsibility lies with the operator. 

Module labeling

The plug-in I/O module has a removable transparent cover (the label holder) for
insertion of a label.

8172z11

Disposal

The devices are considered electronics devices for disposal in terms of European
Directive and may not be disposed of as domestic garbage.
• Dispose of the devices through channels provided for this purpose.
• Comply with all local and currently applicable laws and regulations.

Engineering, mounting, installation

Please refer to the following documents

Document Number
TX-I/O™ functions and operation CM110561
TX-I/O™ Engineering and installation manual CM110562
Replacement of legacy modules CM110563

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Mounting

Permitted orientation The TX-I/O™ devices can be installed in any orientation:

It is important to provide adequate ventilation so that the admissible ambient

temperature (max. 50°C) is not exceeded.

Technical data

Supply Operating voltage range DC 21.5 ... 26 V (SELV / PELV)

(bus connector on side) or DC 24 V class 2 (US)
Max. power consumption TXM1.8X 2.2 W
TXM1.8X-ML 2.3 W
(for the sizing of power supplies, see CM110562)

Protection All terminals of the modules Against shortcut and incorrect

wiring with AC / DC 24 V
Bus connector on side No protection!

Field devices
Insulation resistance The of the connected field devices against mains voltage must comply with the
requirements for safety extra-low voltage (SELV) or protection by extra-low voltage
(PELV) as per HD 384.
Measuring cables Cable material Solid or stranded copper wire
Cable cross section See manual CM110562
Permitted cable length max. 300 m

DC output (field supply) Nominal voltage (derived in the module from the DC24 V
( , Terminals 3, 11, 20, 28) module supply voltage)
Admissible current per module Max. 200 mA
(total for all 4 terminals)

AC/DC output Voltage AC / DC 12 ... 24 V

(field supply) Admissible current per module Max. 4 A
(total for all 4 terminals)
( , Terminals 7, 15, 24, 32) Fuse T 10A, in power supply module /
bus connection module
Caution! Wiring of the AC/DC 24 V supply:
Use cable cross section suited for 10 A according to local regulations.

Digital inputs / Digital inputs are not electrically separated from the system electronics.
counter inputs Mechanical contacts must be volt-free.
Electronic switches must comply with SELV / PELV standards.
Counter inputs faster than 1 Hz that are routed for more than 10 m in the same
trunking as analog inputs must be shielded.

Contact sensing voltage DC 21.5 ...25 V

Contact sensing current 1.0 mA (initial current 6 mA)
Contact resistance with contacts closed Max. 200Ω
Contact resistance with contacts open Min. 50kΩ

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 Min. closing / Max. Max. Counting
opening time [ms] bounce time frequency
including bouncing [ms] (symmetric)
Maintained contact 60 20
Pulse contact 30 10
Counter mechanic 20 10 25 Hz
Counter electronic ..5 ..0 100 Hz

Counter memory 0 ... 4.3 x 109 (32 bit counter)

Analog inputs Correction of line resistance 1 Ω (calibrated In module)

Signal type Range Under / over range Resolution

(see page 2)
Resistance Pt 1000 and AI Pt1000 0...2500 Ohm 0...2650 Ohm 100 mOhm
resistance transmitter AI 2500 Ohm 0...2500 Ohm 0...2650 Ohm 100 mOhm

Temp. measurement AI PT1K 375 -50…180 -52.5...185.0 °C 10 mK

AI PT1K 385 1) -50...400 (600) °C 1) -52.5...610°C 20 mK
AI NI1000 -50…150 (180) °C 1) -52.5...185.0 °C 10 mK
extended 1)

AI NI1000 -50...150°C -52.5...155.0 °C 10 mK

AI T1 (PTC) 1) -50...130 (150) °C 1) -52.5...155.0 °C 10 mK
AI NTC10K 1) (-40...115 °C) 1) -52.5...155°C 10 mK (25°C)
AI NTC100K 1) (-40 ...125 °C) 1) -52.5...155°C 10 mK (25°C)
1) 180 °C, 600°C, NTC: only with reduced hum injection

Voltage measurement AI 0-10V 2) 0 ... 10 V 2) -1.5...11.5 V 1 mV

2) In case of open connection: negative voltage –3.1 V, 0.05 mA (open circuit detection)

Current measurement AI 4-20mA 4...20 mA 1.6...22.4 mA 1 µA

AI 0-20mA 0...20 mA -3.0...23 mA 1 µA
(25 mA see CM10563)
Load resistance 490 / 440 ohms, pulsing (cyclic interrogation of the I/O points)
Note: if the peripheral device can not drive this load, the signal must be connected
via a current measuring converter.

Analog outputs Signal type Range Under / over range Resolution

Output voltage AO 0-10V 0 … 10 V -0.05...10.6 V 1 mV
Output current max. 1 mA

Output current
I/O points 5 ... 8 only) AO 4-20mA 4 ... 20 mA 3.92...20.96 mA 1 µA
Output voltage ca. DC 15 V
Load resistance 0 ... 500 Ohm

Connection terminals Mechanical design Rising cage terminals

Solid conductors 1 x 0.5 mm2 to 4mm2
or 2 x 0,6 mm∅ to 1.5 mm2
Stranded conductors without 1 x 0.5 mm2 to 2.5 mm2
connector sleeves or 2 x 0,6 mm∅ to 1.5 mm2
Stranded conductors with connector sleeves 1 x 0.25 mm2 to 2.5 mm2
(DIN 46228/1) or 2 x 0,6 mm∅ to 1.5 mm2
Screwdriver No. 1 Screwdriver for slotted or
recessed-head * screws
with shaft diameter ≤ 4.5 mm
* Combined slotted / recessed-
head screws from mid-2012
Max. tightening torque 0.6 Nm
Test pickups (test terminals) For pin diameter 1.8 … 2.0 mm

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Local override Local override / indication device ISO 16 484-2, Section 3.11
(TXM1.8X-ML only)
Classification to EN 60730 Mode of operation of automatic electrical Type 1
controls
Contamination level 2
Mechanical design Protection class III
Housing Protection standard to EN 65029
protection standard Front-plate components in DIN cut-out IP30
Terminal base IP20
Ambient conditions Operation To IEC 60721-3-3
Climatic conditions Class 3K5
Temperature –5 ... 50 °C
Humidity 5 … 95 % rh
Mechanical conditions Class 3M2
Transport / storage To IEC 60721-3-2
Climatic conditions Class 2K3
Temperature –25…70 °C
Humidity 5 … 95 % rh
Mechanical conditions Class 2M2
Standards, directives and Product standard EN 60730-1 Automatic electrical controls for
approvals household and similar use
Electromagnetic compatibility (Applications) For use in residential, commercial,
light-industrial and industrial
environments
EU conformity (CE) CM1T10870xx *)
UL certification (US) UL 916, UL 864,
http://ul.com/database
CSA certification Class 4812
https://www.csagroup.org/serv
ices-industries/product-listing/
RCM-conformity (EMC) CM1T10870en_C1 *)
EAC conformity Eurasia conformity
Environmental compatibility Product environmental declaration (contains CM2E8174 *)
data on RoHS compliance, materials compo-
sition, packaging, environmental benefit,
disposal)

Color Terminal base and plug-in I/O module RAL 7035 (light gray)
Dimensions Housing to DIN 43 880, see "Dimensions"
Weight Without / with packaging TXM1.8X 194 / 215 g
TXM1.8X-ML 211 / 232 g

*) The documents can be downloaded from http://siemens.com/bt/download.

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Connection diagrams (examples)

Digital inputs U
(1) (2) (3) (4) (5)
U Super universal module
K1 Status contact (N/O)
2 4 6 8 10 12 14 16 19 21 K2 Status contact (N/C)
K3 Pulse contact (N/O)
K4 Pulse contact (N/C)
S5 Electronic switch

8174z13
K1 K2 K3 K4 S5

Terminal layout TXM1.8X, TXM1.8X-ML

I/O point (1) (2) (3) (4) (5) (6) (7) (8)
System neutral ⊥ (–) 1) 2 6 10 14 19 23 27 31
Input (+) 4 8 12 16 21 25 29 33

STOP Counter inputs Counter inputs faster than 1 Hz that are routed for more than 10 m in the same trunking
as analog inputs must be shielded.

Analog inputs U
(1) (2) (3)

2 4 6 8 10 12

M B
8174z14

B1 B2 R3
U Super universal module
B1 LG-Ni 1000 temperature sensor
U B2 General temperature sensor
R3 Resistance transmitter r
(1) (2) (3) (4)
B4 Active sensor with DC 24 V supply
2 4 6 8 10 12 14 16 B5 Active sensor with AC / DC supply
3 7 11 B6 Active sensor 0 … 20 mA or 4 … 20 mA
(2-wire)
B7 Active sensor with external supply
DC 24 V

DC 24 V
V

External supply must NOT be earthed

(earth loop)
V

B4 B5 B6 B7

Terminal layout TXM1.8X, TXM1.8X-ML

I/O point (1) (2) (3) (4) (5) (6) (7) (8)
Measuring neutral ⊥ (–) 1) 2 6 10 14 19 23 27 31
Input (+) 4 8 12 16 21 25 29 33
AC/DC sensor supply voltage 2) Selected from: 7, 15, 24, 32
3)
DC +24 V sensor supply voltage Selected from: 3, 11, 20, 28

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Analog outputs U
U Super universal module
(5) (6) (7) (8)
Y1 Actuator with input
19 21 23 25 27 29 31 33 DC 0 ..10 V or 4 ... 20 mA
7 11
Y2 … Y4 General device with input
DC 0 ..10 V or 4 ... 20 mA,

DC 24 V
Supply AC / DC, DC 24 V or

V
externally

8174z15_01
V
External supply must NOT be
Y1 Y2 Y3 Y4
earthed (earth loop)

Terminal layout tension TXM1.8X, TXM1.8X-ML

I/O point (1) (2) (3) (4) (5) (6) (7) (8)
System neutral ⊥ (–) 1) 2 6 10 14 19 23 27 31
Output (+) 4 8 12 16 21 25 29 33
AC/DC operating voltage 2) Selected from: 7, 15, 24, 32 2)
3)
DC +24 V operating voltage Selected from: 3, 11, 20, 28 3)

Terminal layout current TXM1.8X, TXM1.8X-ML

I/O point (1) (2) (3) (4) (5) (6) (7) (8)
System neutral ⊥ (–) 1) -- -- -- -- 19 23 27 31
Output (+) -- -- -- -- 21 25 29 33
AC/DC operating voltage 2) Selected from: 7, 15, 24, 32 2)
3)
DC +24 V operating voltage Selected from: 3, 11, 20, 28 3)

1)
All measuring / system neutral terminals are interconnected, not in the terminal base
but in the plug-in I/O module. When this unit is pulled outward (into the "parking"
position) there is no connection.
– The system neutral of a digital input can be connected to any system neutral
terminal
– With analog inputs and outputs, the measuring / system neutral must always be
connected to the terminal associated with that I/O point.
2)
All AC/DC 24V supply terminals are interconnected
(in the I/O module, not in the terminal base).
They are protected in the power supply module / bus connection module (T10A).
Caution! Wiring of the AC 24/DC V supply (terminals 7, 15, 24, 32):
Use cable cross section suited for 10 A according to local regulations.
3)
All DC 24 V supply terminals are interconnected.
They are protected in the module against shortcut and incorrect wiring.

For wiring details refer to the TX-I/O™ Engineering and installation manual, CM110562.

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Dimensions

Dimensions in mm
90
67
45

77.5
70
44
22
98
108
7.1
8172M01

64 3

Published by:
Siemens Switzerland Ltd.
Building Technologies Division
International Headquarters
Gubelstrasse 22
6301 Zug
Switzerland
Tel. +41 41-724 24 24 © Siemens Switzerland Ltd 2007
www.siemens.com/buildingtechnologies Delivery and technical specifications subject to change

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 8 175

TX-I/O™

Relay modules TXM1.6R

TXM1.6R-M
 Two fully compatible versions:
– TXM1.6R: – 6 volt-free relay outputs
– Individual I/O point signaling with green I/O status LED
– TXM1.6R-M: As TXM1.6R, but with the following additional features
– Three-color I/O status LED (red, yellow or green)
– Local override (to ISO 16 484-2)
 6 relay outputs, which can be individually configured as:
– Maintained contact or pulse, 1 … 3-stage
– Three-position control output with stroke algorithm
 Mixed voltages (AC 250 V mains voltage and SELV/PELV 24 V) as well as
mixed phases are permitted on adjacent I/O points of the module
 Compact DIN format, small footprint
 Separate terminal base and plug-in I/O module for convenient handling
– Self-establishing bus connection for maximum ease of installation
– Terminal isolation function for fast commissioning
– I/O module replaceable in seconds, without rewiring and without affecting
the full functioning of the remaining I/O modules
 Terminal strips are required to connect N and PE of the field devices
 Simple strategy for operation and display
– I/O status LED for each I/O point
– LEDs for fast diagnostics
 Double-sided labels for identification of all I/O points

CM2N8175en_11
2023-05-31 Smart Infrastructure
Functions

The modules support the following I/O functions:

Signal type (TRA) Signal type Description

BO Relay NO 250V Q250 Maintained contact relay, changeover contact
BO Relay NC 250V N/O, N/C contact

BO Pulse On-Off Q250-P On/off pulse Q250-P With self-latching and 2 channels
Q250A-P Q250A-P With dual-winding switch

BO Pulse *) Pulse

MO Steps Q-M1…M4 Multistate maintained contact, 1…6-stage

mutually exclusive electronic relay interlock

MO Pulse Q250-P1…P5 Multistate pulse, 1…5-stage

mutually exclusive electronic relay interlock

BO 3-Pos Relay Y250T Pulse, control signal, three-position output,

internal algorithm for stroke running time

*) DESIGO V4, V5: Use MO Q250-P1.

For a detailed description of these functions, please refer to document CM110561,

"TX-I/O™ functions and operation".

Notes  Q250B Use TXM1.6RL with BO Bistable NO / NC

For switched current <100mA, see CM110563, Replacement of legacy
signal types.
 QD Feedback must be implemented using separate digital inputs
e.g. with TXM1.8D, see CM110563.

Compatibility

Support of signal types and functions in different building automation and control
systems: see TX-I/O Engineering and installation manual, CM110562

Type summary

ASN Relay module TXM1.6R

Relay module TXM1.6R-M with local override

Delivery The terminal base and the plug-in I/O module are interconnected and delivered in the
same box.

Accessories The available accessories include address keys, label sheets, and spare transparent
label holders. Refer to data sheet CM2N8170.

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Technical and mechanical design

For a description of the features common to all TX-I/O™ modules, please refer to the
TX-I/O™ Engineering and installation manual, document CM110562.

Indicators and operator controls

Connection terminals (No. 1 screwdriver for slotted or

recessed-head * screws)
with test pickup (for 1.8...2 mm pins) and terminal number

Signal designation

Override status LEDs (yellow)

Address key and module status LED

I/O point numbers

Override button (TXM1.6R-M only)

I/O status LEDs (TXM1.6R: green;

TXM1.6R-M: colors can be configured, green/yellow/red)

* Combined slotted / recessed-head screws from mid-2012

I/O status LEDs  The I/O status LEDs indicate the status of the relays
 The LEDs on the TXM1.6R are green.
 In the case of the TXM1.6R-M the LEDs are three-colored. If the I/O function
supports it, the module can display Alarm = red and Service = yellow, besides
Normal = green
 The LEDs are also used for diagnostics

Module status LEDs  The module status LED illuminates the transparent address key
 The (green) LED shows the module status as a whole (as opposed to the I/O points)
 It is also used for diagnostics

Address key  The module operates only with the address key inserted
 The module address is mechanically encoded in the address key
 When replacing the plug-in I/O module, the address key must be swiveled outward. It
remains plugged into in the terminal base.

Terminals  The relay contacts of the individual I/O points are volt-free, and are not
interconnected. The switched voltage must be provided separately for each I/O point.
 Mixed voltages (AC 250 V mains voltage and SELV/PELV 24 V) as well as mixed
phases are permitted on adjacent I/O points of the module

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Local override (TXM1.6R-M only)

Override button  Pressing an override button in the middle enables/disables local override
 Pressing "+" for one of the I/O points activates the relay or switches control to the
next stage up (depending on function)
Repeated or sustained pressure switches several stages until the function stops at
the highest stage.
 Pressing "–" for one of the I/O points deactivates opens the relay or switches control
to the next stage down (depending on function)
Repeated or sustained pressure switches several stages until the function stops at
the lowest stage.

Override status LED  The yellow "Override" LED indicates that local override is active

 All safety-relevant functions must be implemented with external solutions

Warning  The local override must not be used for safety shutdown operations
 In compliance with the standard (ISO 16 484-2, Section 3.110), the module
executes all local overrides directly, without safety precautions or interlocks.
 Full responsibility lies with the operator. 

Module labeling

The plug-in I/O module has a removable transparent cover (the label holder) for
insertion of a label.

1
8172z11

Disposal

The device is classified as waste electronic equipment in terms of the European Direc-
tive 2012/19/EU and should not be disposed of as unsorted municipal waste.
The relevant national legal rules are to be adhered to.
Regarding disposal, use the systems setup for collecting electronic waste.
Observe all local and applicable laws.

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Engineering, mounting, installation

Please refer to the following documents

Document Number
TX-I/O™ functions and operation CM110561
TX-I/O™ Engineering and installation manual CM110562
Replacement of legacy modules CM110563 *)

*) Login with Siemens account necessary.

Mounting

Permitted orientation The TX-I/O™ devices can be installed in any orientation:

It is important to provide adequate ventilation so that the admissible ambient
temperature (max. 50°C) is not exceeded.

Technical data

Supply Operating voltage DC 21.5 ... 26 V

(bus connector on side) Extra low voltage SELV or PELV
in accordance with HD384
Max. power consumption TXM1.6R 1.7 W
TXM1.6R-M 1.9 W
(for the sizing of power supplies, see CM110562)

Protection Bus connector on side No protection against shortcut and

incorrect wiring with AC / DC 24 V

Switching outputs Number of switching outputs 6 (changeover contact)

External fuse protection for incoming cable
 Slow blow fusible link Max. 10 A
 Circuit breaker Max. 13 A
Circuit breaker tripping characteristic Type B, C or D to EN 60898
Contact data for AC Voltage range min. AC 12 V max. AC 250 V
Current, resistive load max. 4 A
Current, inductive load (cos phi ≥ 0.6) max. 3 A
Switching current min. 1 mA at AC 250 V
min. 10 mA at AC 12 V
Current on make max. 20 A during max. 10 ms
max. 10 A during max. 1 s
For UL applications 3 FLA, 9 LRA, 1/4 HP, 4 (3) A
Contact data for DC Voltage range min. DC 12 V, max. DC 30 V
Current, resistive load max. 3 A at DC 30 V
min. 10mA at DC 12 V
Current on make max. 3 A
Service life of contact With 0.1 A resistive 8 million switching operations
for AC 250 V With 0.5 A resistive 2 million switching operations
With 4.0 A resistive (N/O) 0.2 million switching operations
Reduction factor with inductive load 0.6 (max. 3 A inductive)
(cos phi ≥ 0.6)
Insulation resistance Reinforced insulation between relay outputs and AC 3750 V, to EN 60 730-1
system electronics
Mixed voltages (AC 250 V mains voltage and SELV/PELV 24 V) as well as
mixed phases are permitted on adjacent I/O points of the module

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Connection terminals Mechanical design Cage clamp terminals
Solid conductors 1 x 0.5 mm2 to 4mm2
or 2 x 0,6 mm to 1.5 mm2
Stranded conductors without connector sleeves 1 x 0.5 mm2 to 2.5 mm2
or 2 x 0,6 mm to 1.5 mm2
Stranded conductors with connector sleeves 1 x 0.25 mm2 to 2.5 mm2
(DIN 46228/1) or 2 x 0,6 mm to 1.5 mm2
Screwdriver No. 1 Screwdriver for slotted or
recessed-head * screws
with shaft diameter ≤ 4.5 mm
* Combined slotted / recessed-
head screws from mid-2012
Max. tightening torque 0.6 Nm
Test pickups (terminals) For pin diameter 1 x 1.8 … 2.0 mm

Local override Local override device ISO 16 484-2, Section 3.11

(TXM1.6R-M only)

Classification Mode of operation of automatic electrical controls Type 1

to EN 60730 Contamination level 2
Mechanical design Devices are suitable for use in equip-
ment with protective class I and II
Housing Protection standard to EN 65029
protection standard Front-plate components in DIN cut-out IP30
Terminal base IP20

Ambient conditions Operation To IEC 60721-3-3

Climatic conditions Class 3K5
Temperature -5...50 °C
Humidity 5…95 % rh
Mechanical conditions Class 3M2
Transport / storage To IEC 60721-3-2
Climatic conditions Class 2K3
Temperature -25…70 °C
Humidity 5…95 % rh
Mechanical conditions Class 2M2

Standards, directives and Product standard EN 60730-1 Automatic electrical controls for
approvals household and similar use
Electromagnetic compatibility (Applications) For use in residential, commercial
and industrial environments
EU conformity (CE) CM1T10870 *)
RCM conformity (EMC) T10870en_C1 *)
UL approbation UL 916, UL 864

Environmental The product environmental declaration contains CM2E8175 *)

compatibility data on RoHS compliance, materials composition,
packaging, environmental benefit, disposal)

Color Terminal base and plug-in I/O module RAL 7035 (light gray)
Dimensions Housing to DIN 43 880, see "Dimensions"
Weight Without / with packaging TXM1.6R 231 / 252 g
TXM1.6R-M 241 / 262 g

*) The documents can be downloaded from http://siemens.com/bt/download.

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Siemens TXM1.6R, TXM1.6R-M – Relay modules CM2N8175en_11

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Connection diagrams (examples)

Terminal layout TXM1.6R, TXM1.6R-M

I/O point (1) (2) (3) (4) (5) (6)
Supply 3 9 15 20 26 32
N/O contact 2 8 14 21 27 33
N/C contact 4 10 16 19 25 31

For functions with several I/O points:

 Always use adjacent I/O points
 Each function must be confined to one module only
 The I/O points have a fixed sequence within the function, e.g. the first I/O point is for
switch-off.

Maintained contact U U Relay module

BO Relay NO 250V (1) (2) (3)
BO Relay NC 250V
2 4 8 10 14 16 Q1 Switched load
AC / DC 24 ... 230V

3 9 15
(N/O contact)
Q2 Switched load
(N/C contact)
K3
K3 Step switch /
8175z13_01 pulse switch /
Q1 Q2
bistable relay

On/off pulse U Q250-P Q250A-P

U Relay module
BO Pulse On-Off (1) (2) (3) (4)
Self-latching and 2 K1 Power contactor,
channels (Q250-P) 2 4 8 10 14 16 21 19 self-latching
3 9 15 20
Dual-winding switch K2 Dual-winding stepping
AC / DC 24 ... 230 V

AC / DC 24 ... 230 V

(Q250A-P) switch, bistable relay

Pulse on I/O point (2) = K1 ON
Pulse on I/O point (1) = K1 OFF
8175z14

K1 K2
Pulse on I/O point (4) = K2 ON
Pulse on I/O point (3) = K2 OFF

Pulse control for single- U U Relay module

stage load with control (1) (2) (3) (4)
K1 Power contactor,
from two separate
self-latching
control loops of equal 2 4 8 10 14 16 21 19
3 9 15 20
status Control circuit 1:
AC / DC 24 ... 230 V

BO Pulse On-Off Pulse on I/O point (2) = ON

Pulse on I/O point (1) = OFF

Control circuit 2:
8175z19

K1
Pulse on I/O point (4) = ON
Pulse on I/O point (3) = OFF

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Pulse control for single- U U Relay module
stage load with control of (1) (2)
K1 Power contactor,
equal status from two
self-latching
remote switching locations 2 4 8 10
3 9
BO Pulse On-Off Control circuit 1:
S1 Pulse on I/O point (2) = ON
Pulse on I/O point (1) = OFF
S3 S2 S4
External control location A:
K1

8175z20
AC / DC 24 ... 230 V S1 OFF button
S2 ON button

External control location B:

S3 OFF button
S4 ON button

Maintained contact, U U Relay module

3-stage (1) (2) (3)
MO Steps
2 4 8 10 14 16 K1, K2, K3 Contactors for
3 9 15
Stages 1…3

I/O point (1) ON = Stage 1

K1 K2 K3 I/O point (2) ON = Stage 2
8175z15

I/O point (3) ON = Stage 3

AC / DC 24 ... 230 V

Pulse, 1-stage

DESIGO V4, V5: Use Q250-P1

DESIGO TRA Use BO Pulse

Pulse, 3-stage U U Relay module

MO Pulse (1) (2) (3) (4)
K1, K2, K3 Contactors with self-
latching feature
2 4 8 10 14 16 21 19
3 9 15 20 for Stages 1 … 3
**) Pulse on I/O point (1) = OFF
Pulse on I/O point (2) = Stage 1
AC / DC 24 ... 230 V

Pulse on I/O point (3) = Stage 2

K2 *) K1 *) K1 *) Pulse on I/O point (4) = Stage 3

K3 *) K3 *) K2 *) *) External self-latching is
optional
**) For other means of control,
8175z16

K1 K2 K3
replace bridge with external
circuit

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Smart Infrastructure 2023-05-31
Pulse control for a three- U1 U2
stage load with control (1) (2) (3) (4) (1) (2) (3) (4)
from two control loops of
2 4 8 10 14 16 21 19 2 4 8 10 14 16 21 19
equal status 3 9 15 20 3 9 15 20
MO Pulse

K2 *) K1 *) K1 *)

K3 *) K3 *) K2 *)

8175z21
K1 K2 K3
AC / DC 24 ... 230 V

U1, U2 Relay modules K1, K2, K3 Contactors with self-latching

feature for Stages 1 … 3
*) External self-latching is optional

Control loop 1: Control loop 2:

U1 Pulse on I/O point (1) = OFF U2 Pulse on I/O point (1) = OFF
U1 Pulse on I/O point (2) = Stage 1 U2 Pulse on I/O point (2) = Stage 1
U1 Pulse on I/O point (3) = Stage 2 U2 Pulse on I/O point (3) = Stage 2
U1 Pulse on I/O point (4) = Stage 3 U2 Pulse on I/O point (4) = Stage 3

Control signal, three- U

position output (1) (2)
BO 3-Pos Relay U Relay module
2 4 8 10
AC / DC 24 ... 230 V

3 9

Y1 Y2 Y1 Control signal OPEN

M Y2 Control signal CLOSE
8175z17

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Dimensions

Dimensions in mm

90
67
45

77.5
70
44
22
98
108
7.1
8172M01

64 3

Published by:
Siemens Switzerland Ltd.
Smart Infrastructure
Global Headquarters
Theilerstrasse 1a
CH-6300 Zug
Switzerland
Tel. +41 58 724-2424 © Siemens Switzerland Ltd 2007
www.siemens.com/buildingtechnologies Delivery and technical specifications subject to change

10/10

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 8 172

TX-I/O™

Digital input modules TXM1.8D

TXM1.16D
• Two fully compatible versions:
– TXM1.8D: 8 inputs, each with a three-color LED (green, yellow or red)
– TXM1.16D: As TXM1.8X, but 16 inputs, each with a green LED
• 8 or 16 digital inputs; individually configurable for status signals,
status pulses (with a memory function) or counter pulses (up to 10 Hz)
• Compact DIN format, small footprint
• Separate terminal base and plug-in I/O module for convenient handling
– Self-establishing bus connection for maximum ease of installation
– Terminal isolation function for fast commissioning
– I/O module replaceable in seconds, without rewiring and without affecting
the full functioning of the remaining I/O modules
• All terminals are directly on the I/O modules, allowing direct connection of
field devices without additional terminal strips.
• Simple strategy for operation and display
– I/O status LED for each I/O point; mode of operation (N/C or N/O) depends
on I/O function
– LEDs for fast diagnostics
• Double-sided labels for identification of all I/O points

CM2N8172en_07
2019-09-01 Building Technologies
Functions

The modules support the following I/O functions:

Function Signal type (TRA) Signal Description

type
Status indication BI NO D20 Volt-free, interrogation (maintained contact), N/O contact
BI NC D20R Volt-free, interrogation (maintained contact), N/C contact

Status pulses BI Pulse NO D20S Volt-free, interrogation (pulse)

BI Pulse NC N/O / N/C contact

Button input BI Push NO -- Button input single / dual , volt-free

BI Push NC N/O / N/C contact

Status multistate MI Switch -- Multistate input, 2...8-stage, volt-free, interrogation

Counter pulses CI Mech (10/25Hz) C Volt-free, N/O contact, interrogation (pulse, max. 10 Hz)
(TXM1.16D: I/O points1 ... 8 only)

For a detailed description of these functions, please refer to document CM1105761,

"TX-I/O™ Functions and operation".

Compatibility

Support of signal types and functions in different building automation and control
systems: see TX-I/O Engineering and installation manual, CM110562

Type summary

ASN Digital input module TXM1.8D

Digital input module TXM1.16D

Delivery The terminal base and the plug-in I/O module are interconnected and delivered in the
same box.

Accessories The available accessories include address keys, label sheets, and spare transparent
label holders. Refer to data sheet CM2N8170.

Technical and mechanical design

For a description of the features common to all TX-I/O™ modules, please refer to the
TX-I/O™ Engineering and installation manual, document CM110562.

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Indicators and operator controls

Connection terminals (No. 1 screwdriver for slotted or

recessed-head * screws)
with test pickup (for 1.8...2 mm pins) and terminal number

Signal designation

Address key and

module status LED

I/O point numbers

(I/O points 9 ... 16: TXM1.16D only)

I/O status LEDs

(TXM1.8D: Configurable - green/yellow/red
TXM1.16D: Green)

* Combined slotted / recessed-head screws from mid-2012

I/O status LEDs • The I/O status LEDs indicate the status of the inputs and outputs (peripheral
devices)
• The LEDs on the TXM1.16D are green
• In the case of the TXM1.8D the LEDs are three-colored. If the I/O function supports
it, the module can display Alarm = red and Service = yellow, besides Normal = green
• The LEDs are also used for diagnostic purposes

Module status LED • The module status LED illuminates the transparent address key
• The (green) LED shows the status of the module as a whole (as opposed to the
status of the I/O points)
• It is also used for diagnostics

Address key • The module operates only with the address key inserted
• The module address is mechanically encoded in the address key
• When replacing the plug-in I/O module, the address key must be swiveled outward. It
remains plugged into in the terminal base.

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Module labeling

The plug-in I/O module has a removable transparent cover (the label holder) for
insertion of a label.

8172z11
Disposal

The devices are considered electronics devices for disposal in terms of European
Directive and may not be disposed of as domestic garbage.
• Dispose of the devices through channels provided for this purpose.
• Comply with all local and currently applicable laws and regulations.

Engineering, mounting, installation

Please refer to the following documents

Document Number
TX-I/O™ Functions and operation CM110561
TX-I/O™ Engineering and installation manual CM110562
Replacement of legacy modules CM110563

Mounting

Permitted orientation The TX-I/O™ devices can be installed in any orientation:

It is important to provide adequate ventilation so that the admissible ambient

temperature (max. 50°C) is not exceeded.

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Siemens TXM1.8D, TXM1.16D – Digital input modules CM2N8172en_07

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Technical data

Supply Operating voltage DC 21.5 ... 26 V (SELV / PELV)

(bus connector on side) or DC 24 V class 2 (US)
Max. power consumption TXM1.8D 1.1 W
TXM1.16D 1.4 W
(for the sizing of power supplies, see CM110562)

Protection All terminals of the modules Against shortcut and incorrect

wiring with AC / DC 24 V
Bus connector on side No protection!

Field devices
Insulation resistance The of the connected field devices against mains voltage must comply with the
requirements for safety extra-low voltage (SELV) or protection by extra-low voltage
(PELV) as per HD 384.
Measuring cables Cable material Solid or stranded copper wire
Cable cross section See manual CM110562
Permitted cable length max. 300 m

Digital inputs / Digital inputs are not electrically separated from the system electronics.
counter inputs *) Mechanical contacts must be volt-free
Electronic switches must comply with SELV / PELV standards.

Contact sensing voltage DC 21.5 ...25 V

Contact sensing current 1.6 mA (initial current 10 mA)
Contact resistance with contacts closed Max. 200Ω
Insulation resistance with contacts open Min. 50kΩ

Min. closing / Max. bounce Max. Counting

opening time [ms] time [ms] frequency
including bouncing (symmetric)
Maintained contact 80 40
Pulse contact 50 30
Counter *) 40 30 10 Hz

Counter memory *) 0 ... 4.3 x 109 (32 bit counter)

*) Counting function for TXM1.16D: I/O points 1 ... 8 only

Connection terminals Mechanical design Rising cage terminals

Solid conductors 1 x 0.5 mm2 to 4mm2
or 2 x 0,6 mm∅ to 1.5 mm2
Stranded conductors without connector sleeves 1 x 0.5 mm2 to 2.5 mm2
or 2 x 0,6 mm∅ to 1.5 mm2
Stranded conductors with connector sleeves 1 x 0.25 mm2 to 2.5 mm2
(DIN 46228/1) or 2 x 0,6 mm∅ to 1.5 mm2
Screwdriver No. 1 Screwdriver for slotted or
recessed-head * screws
with shaft diameter ≤ 4.5 mm
* Combined slotted / recessed-
head screws from mid-2012
Max. tightening torque 0.6 Nm
Test pickups (terminals) For pin diameter 1 x 1.8 … 2.0 mm

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Classification to EN 60730 Mode of operation of automatic electrical controls Type 1
Contamination level 2
Mechanical design Protection class III

Housing Protection standard to EN 65029

protection standard Front-plate components in DIN cut-out IP30
Terminal base IP20
Ambient conditions Operation To IEC 60721-3-3
Climatic conditions Class 3K5
Temperature –5 ... 50 °C
Humidity 5 … 95 % rh
Mechanical conditions Class 3M2
Transport / storage To IEC 60721-3-2
Climatic conditions Class 2K3
Temperature –25…70 °C
Humidity 5 … 95 % rh
Mechanical conditions Class 2M2

Standards, directives and Product standard EN 60730-1 Automatic electrical controls for
approvals household and similar use
Electromagnetic compatibility (Applications) For use in residential,
commercial, light-industrial and
industrial environments
EU conformity (CE) CM1T10870xx *)
UL certification (US) UL 916, UL 864,
http://ul.com/database
CSA certification Class 4812
https://www.csagroup.org/service
s-industries/product-listing/
RCM-conformity (EMC) CM1T10870en_C1 *)
EAC conformity Eurasia conformity
Environmental compatibility Product environmental declaration (contains data CM2E8172 *)
on RoHS compliance, materials composition,
packaging, environmental benefit, disposal)

Color Terminal base and plug-in I/O module RAL 7035 (light gray)
Dimensions Housing to DIN 43 880, see "Dimensions"
Weight Without / with packaging TXM1.8D 164 / 185 g
TXM1.16D 199 / 220 g

*) The documents can be downloaded from http://siemens.com/bt/download.

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Connection diagrams (examples)

U U Digital input module

(1) (2) (3) (4) (5)
K1 Status contact (N/O)
1 2 3 4 5 6 7 8 9 10 K2 Status contact (N/C)
K3 Pulse contact (N/O)
K4 Pulse contact (N/C)
S5 Electronic switch

8172z13
K1 K2 K3 K4 S5

Terminal layout

TXM1.8D, TXM1.16D TXM1.16D only

I/O point (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16)
System neutral ⊥ (–) 1) 1 3 5 7 9 11 13 15 18 20 22 24 26 28 30 32
Input (+) 2 4 6 8 10 12 14 16 19 21 23 25 27 29 31 33

1)
Terminals 1, 3, 5 etc. are system neutral terminals
– They are interconnected, not in the terminal base but in the plug-in I/O module.
This means that when the I/O module is removed, there is no connection.
– The system neutral of a digital input can be connected to any system neutral
terminal

For wiring details refer to the TX-I/O™ Engineering and installation manual, CM110562.

7/8

Siemens TXM1.8D, TXM1.16D – Digital input modules CM2N8172en_07

Building Technologies 2019-09-01
Dimensions

Dimensions in mm

90
67
45

77.5
70
44
22
98
108
7.1
8172M01

64 3

Published by:
Siemens Switzerland Ltd.
Building Technologies Division
International Headquarters
Gubelstrasse 22
6301 Zug
Switzerland
Tel. +41 41-724 24 24 © Siemens Switzerland Ltd 2007
www.siemens.com/buildingtechnologies Delivery and technical specifications subject to change

8/8

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s 8 173

TX-I/O™

Universal modules TXM1.8U

TXM1.8U-ML
• Two fully compatible versions:
– TXM1.8U: 8 inputs/outputs with LED signal / fault indication
– TXM1.8U-ML: As TXM1.8U, but with additional local override facility
with LCD display (LO/ID to ISO 16 484-2)
• 8 universal I/O points, individually configurable as
– Digital input: maintained contact, pulse or counter
– Analog input: sensor, 0..10V
– Analog output: 0..10V
• Compact DIN format, small footprint
• Separate terminal base and plug-in I/O module for convenient handling
– Self-establishing bus connection for maximum ease of installation
– Terminal isolation function for fast commissioning
– I/O module replaceable in seconds, without rewiring and without affecting
the full functioning of the remaining I/O modules
• All terminals are directly on the I/O modules, allowing direct connection of
field devices without additional terminal strips.
• Simple strategy for operation and display
– I/O status LED for each I/O point; mode of operation (N/C or N/O) and
brightness depend on I/O function
– LEDs and LCD for fast diagnostics
• Double-sided labels for identification of all I/O points

CM2N8173en_11
2019-09-01 Building Technologies
Functions

The modules support the following I/O functions:

Function Signal type Signaltyp Description

Status signal BI NO D20 Volt-free, interrogation (maintained contact), N/O contact
BI NC D20R Volt-free, interrogation (maintained contact), N/C contact
Status pulses BI Pulse NO D20S Volt-free, interrogation (pulse), N/O, N/C contact
BI Pulse NC
Counter pulses Volt-free, N/O contact, interrogation (pulse)
CI El (100Hz) C Counting frequency max. 100 Hz (electronic counter)
CI Mech (10/25Hz) max. 25 Hz (mechanical counter)
Voltage, AI 0-10V U10 DC voltage 0 ... 10 V
resistance and
AI 2500 Ohm R2K5 Resistance 2500 Ω
temperature
AI Ni1000 extended Ni1K Temperature sensor LG-Ni 1000 ohms, up to 180 °C

AI Ni1000 R1K Temperature sensor LG-Ni 1000 ohms

AI PT1K375 Pt1K 375 Temperature sensor Pt 1000 (USA)

AI PT1K385 Pt1K 385 Temperature sensor Pt 1000 (Europe)

AI Pt1000 P1K Resistance Pt 1000 ohms and resistance transmitter

AI T1 (PTC) T1 Temperature sensor PTC

AI NTC10K NTC10 K Temperature sensor NTC 10 K

AI NTC100K NTC100 K Temperature sensor NTC 100 K

Proportional AO 0-10V Y10S Proportional control output, DC 0 ... 10 V, with storage of

output signal control value

For a detailed description of these functions, please refer to document CA110561,

"TX-I/O™ functions and operation".

Compatibility

Support of signal types and functions in different building automation and control
systems: see TX-I/O Engineering and installation manual, CM110562

Type summary

ASN Universal module TXM1.8U

Universal module TXM1.8U-ML with LCD display and local override

Delivery The terminal base and the electronic plug-in unit are interconnected and delivered in
the same box.

Accessories The available accessories include address keys, label sheets, and spare transparent
label holders. Refer to data sheet CM2N8170.

2/10

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Building Technologies 2019-09-01
Technical and mechanical design

For a description of the features common to all TX-I/O™ modules, please refer to the
TX-I/O™ Engineering and installation manual, document CM110562.

Indicators and operator controls

Connection terminals (No. 1 screwdriver for slotted or

recessed-head * screws)
with test pickup (for 1.8...2 mm pins) and terminal number
Signal designation

Override status LEDs (yellow)

Address key and module status LED

LCD panel (TXM1.8U-ML only)

I/O point numbers

Override button (TXM18U-ML only)

I/O status LEDs (green)

* Combined slotted / recessed-head screws from mid-2012

I/O status LEDs • The I/O status LEDs (green) indicate the status of the inputs and outputs (peripheral
devices)
• They are also used for diagnostics

Module status LED • The module status LED illuminates the transparent address key
• The LED (green) shows the module status as a whole (as opposed to the status of
the I/O points)
• It is also used for diagnostics

Address key • The module operates only with the address key inserted
• The module address is mechanically encoded in the address key
• When replacing the I/O module, the address key must be swiveled outward. It
remains plugged into in the terminal base.

3/10

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Building Technologies 2019-09-01
Local override and LCD display (TXM1.8U-ML only)

For a detailed description, please refer to document CM110561, "TX-I/O™ Functions

and operation".

Override button • Pressing an override button in the middle enables or disables the local override
• Pressing "+" or "–" respectively increases or reduces the output value.
• Only outputs can be overwritten. Any attempt to overwrite an input results in an error
indication.
Override status LED • The yellow "Override" LED indicates that local override is active

LCD display • The following information is displayed for each I/O point:
– Configured signal type
– Symbolic display of process value
– Information for diagnostics.
• All safety-relevant functions must be implemented with external solutions
Warning • The local override must not be used for safety shutdown operations
• In compliance with the standard (ISO 16 484-2, Section 3.110), the module
executes all local overrides directly, without safety precautions or interlocks.
 Full responsibility lies with the operator. 

Module labeling

The plug-in I/O module has a removable transparent cover (the label holder) for
insertion of a label.

1
8172z11

Disposal

The devices are considered electronics devices for disposal in terms of European
Directive and may not be disposed of as domestic garbage.
• Dispose of the devices through channels provided for this purpose.
• Comply with all local and currently applicable laws and regulations.

4/10

Siemens TXM1.8U, TXM1.8U-ML – Universal modules CM2N8173en_11

Building Technologies 2019-09-01
Engineering, mounting, installation

Please refer to the following documents

Document Number
TX-I/O™ functions and operation CM110561
TX-I/O™ Engineering and installation manual CM110562
Replacement of legacy modules CM110563

Mounting

Permitted orientation The TX-I/O™ devices can be installed in any orientation:

It is important to provide adequate ventilation so that the admissible ambient

temperature (max. 50°C) is not exceeded.

Technical data

Supply Operating voltage range DC 21.5 ... 26 V (SELV / PELV) or

(bus connector on side) DC 24 V class 2 (US)
Max. power consumption TXM1.8U 1.5 W
TXM1.8U-ML 1.8 W
(for the sizing of power supplies, see CM110562)

Protection All terminals of the modules Against shortcut and incorrect

wiring with AC / DC 24 V
Bus connector on side No protection!
Field devices
Insulation resistance The of the connected field devices against mains voltage must comply with the
requirements for safety extra-low voltage (SELV) or protection by extra-low voltage
(PELV) as per HD 384.
Measuring cables Cable material Solid or stranded copper wire
Cable cross section See manual CM110562
Permitted cable length max. 300 m

AC/DC output Voltage AC / DC 12 ... 24 V

(field supply) Admissible current per module Max. 4 A
(total for all 4 terminals)
( , Terminals 7, 15, 24, 32) Fuse T 10A, in power supply
module/bus connection module
Caution! Wiring of the AC/DC 24 V supply:
Use cable cross section suited for 10 A according to local regulations.

5/10

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Building Technologies 2019-09-01
Digital inputs / Digital inputs are not electrically separated from the system electronics.
counter inputs Mechanical contacts must be volt-free.
Electronic switches must comply with SELV / PELV standards.
Counter inputs faster than 1 Hz that are routed for more than 10 m in the same
trunking as analog inputs must be shielded.

Contact sensing voltage DC 21.5 ...25 V

Contact sensing current 1.0 mA (initial current 6 mA)
Contact resistance with contacts closed Max. 200Ω
Contact resistance with contacts open Min. 50kΩ

Min. closing / Max. Max. Counting

opening time [ms] bounce time frequency
including bouncing [ms] (symmetric)
Maintained contact 60 20
Pulse contact 30 10
Mechanical counter 20 10 25 Hz
electronic counter ..5 ..0 100 Hz

counter memory 0 ... 4.3 x 109 (32 bit counter)

Analog inputs
Correction of line resistance 1 Ω (calibrated In module)

Signal type (see page 2) Range Under / over range Resolution

Resistance Pt 1000 and P1K 0...2500 Ohm 0...2650 Ohm 100 mOhm
resistance transmitter AI Pt1000 0...2500 Ohm 0...2650 Ohm 100 mOhm

Temp. measurement AI PT1K 375 -50…180 -52.5...185.0 °C 10 mK

AI PT1K 385 1) -50...400 (600) °C 1) -52.5...610°C 20 mK
AI NI1000 extended 1) -50…150 (180) °C 1) -52.5...185.0 °C 10 mK
AI Ni1000 -50...150°C -52.5...155.0 °C 10 mK
AI T1 (PTC) 1)
-50...130 (150) °C 1) -52.5...155.0 °C 10 mK
AI NTC10K 1)
(-40...115 °C) 1) -52.5...155°C 10 mK (25°C)
AI NTC100K 1)
(-40 ...125 °C) 1) -52.5...155°C 10 mK (25°C)
1) 180 °C, 600°C, NTC: only with reduced hum injection

Voltage measurement AI 0-10V 2) 0 ... 10 V 2) -1.5...11.5 V 1 mV

2) In case of open connection: negative voltage –3.1 V, 0.05 mA (open circuit detection)

Analog outputs Signal type Range Under / over range Resolution

Output voltage AO 0-10V 0 … 10 V -0.05...10.6 V 1 mV
Output current max. 1 mA

Connection terminals Mechanical design Rising cage terminals

Solid conductors 1 x 0.5 mm2 to 4mm2
or 2 x 0,6 mm∅ to 1.5 mm2
Stranded conductors without connector sleeves 1 x 0.5 mm2 to 2.5 mm2
Stranded conductors with connector sleeves or 2 x 0,6 mm∅ to 1.5 mm2
(DIN 46228/1) 1 x 0.25 mm2 to 2.5 mm2
or 2 x 0,6 mm∅ to 1.5 mm2
Screwdriver No. 1 Screwdriver for slotted or
recessed-head * screws
with shaft diameter ≤ 4.5 mm
* Combined slotted / recessed-
head screws from mid-2012
Max. tightening torque 0.6 Nm
Test pickups (test terminals) For pin diameter 1.8 … 2.0 mm
Local override Local override / indication device ISO 16 484-2, Section 3.11
(TXM1.8U-ML only)

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Classification to EN 60730 Mode of operation of automatic electrical controls Type 1
Contamination level
Mechanical design 2
Protection class III
Housing Protection standard to EN 65029
protection standard Front-plate components in DIN cut-out IP30
Terminal base IP20
Ambient conditions Operation To IEC 60721-3-3
Climatic conditions Class 3K5
Temperature –5 ... 50 °C
Humidity 5 … 95 % rh
Mechanical conditions Class 3M2
Transport / storage To IEC 60721-3-2
Climatic conditions Class 2K3
Temperature –25…70 °C
Humidity 5 … 95 % rh
Mechanical conditions
Class 2M2

Standards, directives and Product standard EN 60730-1 Automatic electrical controls for
approvals household and similar use
Electromagnetic compatibility (Applications) For use in residential,
commercial, light-industrial and
industrial environments
EU conformity (CE) CM1T10870xx *)
UL certification (US) UL 916, UL 864,
http://ul.com/database
CSA certification Class 4812
https://www.csagroup.org/serv
ices-industries/product-listing/
RCM-conformity (EMC) CM1T10870en_C1 *)
EAC conformity Eurasia conformity
Environmental compatibility Product environmental declaration (contains data CM2E8173 *)
on RoHS compliance, materials composition,
packaging, environmental benefit, disposal)

Color Terminal base and plug-in I/O module RAL 7035 (light gray)
Dimensions Housing to DIN 43 880, see "Dimensions"
Weight Without / with packaging TXM1.8U 179 / 200 g
TXM1.8U-ML 202 / 223 g

*) The documents can be downloaded from http://siemens.com/bt/download.

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Connection diagrams (examples)

Digital inputs U
(1) (2) (3) (4) (5)
U Universal module
K1 Status contact (N/O)
2 4 6 8 10 12 14 16 19 21 K2 Status contact (N/C)
K3 Pulse contact (N/O)
K4 Pulse contact (N/C)
S5 Electronic switch

8174z13
K1 K2 K3 K4 S5

Terminal layout TXM1.8U, TXM1.8U-ML

I/O point (1) (2) (3) (4) (5) (6) (7) (8)
System neutral ⊥ (–) 1) 2 6 10 14 19 23 27 31
Input (+) 4 8 12 16 21 25 29 33

STOP Counter inputs Counter inputs faster than 1 Hz that are routed for more than 10 m in the same trunking
as analog inputs must be shielded.

Analog inputs U
U Universal module
(1) (2) (3)
B1 LG-Ni 1000 temperature sensor
2 4 6 8 10 12 B2 Pt 1000 temperature sensor
R3 Resistance-type sensor
B4 Active sensor with external supply
M B External supply must NOT be earthed
(earth loop)
B5 Active sensor with AC / DC supply
B1 B2 R3

U
(1) (2)

2 4 6 8
V
7
V
V

8173z14

B4 B5

Terminal layout TXM1.8U, TXM1.8U-ML

I/O point (1) (2) (3) (4) (5) (6) (7) (8)
Measuring neutral ⊥ (–) 1) 2 6 10 14 19 23 27 31
Input (+) 4 8 12 16 21 25 29 33
2
AC / DC sensor supply voltage Selected from: 7, 15, 24, 32 2)

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Analog outputs U
U Universal module
(1) (2) (3)
Y1 Actuator with input DC 0 ..10 V
2 4 6 8 10 12 Y2 General device with input
V DC 0 ..10 V, supplied by module
7
Y3 General device with input
DC 0 ..10 V, supplied externally
External supply must NOT be

V
earthed (earth loop)

8173z15
V
Y1 Y2 Y3

Terminal layout TXM1.8U, TXM1.8U-ML

I/O point (1) (2) (3) (4) (5) (6) (7) (8)
System neutral ⊥ (–) 1) 2 6 10 14 19 23 27 31
Output (+) 4 8 12 16 21 25 29 33
2)
AC / DC operating voltage Selected from: 7, 15, 24, 32 2)

1)
All measuring / system neutral terminals are interconnected, not in the terminal base
but in the plug-in I/O module. When this unit is pulled outward (into the "parking"
position) there is no connection.
– The system neutral of a digital input can be connected to any system neutral
terminal
– With analog inputs and outputs, the measuring / system neutral must always be
connected to the terminal associated with that I/O point.

2)
All AC/DC 24V supply terminals are interconnected
(in the I/O module, not in the terminal base).
They are protected in the power supply module / bus connection module (T10A).
Caution! Wiring of the AC/DC 24 V supply (terminals 7, 15, 24, 32):
Use cable cross section suited for 10 A according to local regulations.

For wiring details refer to the TX-I/O™ Engineering and installation manual, CM110562.

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Dimensions

Dimensions in mm
90
67
45

77.5
70
44
22
98
108
7.1

8172M01

64 3

Published by:
Siemens Switzerland Ltd.
Building Technologies Division
International Headquarters
Gubelstrasse 22
6301 Zug
Switzerland
Tel. +41 41-724 24 24 © Siemens Switzerland Ltd 2007
www.siemens.com/buildingtechnologies Delivery and technical specifications subject to change

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