User Manual

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Siemens TX-I/O Engineering and installation guide CM110562en_13
Building Technologies Checking activities 2019-05-15
7.4 Wiring test with unconfigured I/O modules
See also Section 9.5 (diagnostics).
The wiring test is best performed with unconfigured I/O modules (with DC 24 V supply
present and address key swiveled inward – bus master not required).
The default functions (factory-set I/O module status) have been specially designed for
optimal testing. With configured modules, each I/O point would react differently
according to the signal type.
Default functions of the modules
Module
Type
Default function
Equivalent function
Digital input module
TXM1.8D, TXM1.16D
BI Default
BI NO / D20
Universal module
TXM1.8U, TXM1.8U-ML
UIO Default
Description see next page
Super universal module
TXM1.8X, TXM1.8X-ML
UIO Default
Description see next page
Resistance measuring module
TXM1.8P
RI Default
Description see next page
Relay module
TXM1.6R(M), TXM1.6RL
BO Default
BO Relay NO 250V / Q250
Triac module
TXM1.8T
BO Default
BO Triac NO
Blinds module
RXM1.8RB
MO Default
4 x MO Steps (2-stage) / Q-M2
Testing options with default functions
Test
Action
I/O status LED
LCD display
Remark
Testing of inputs
TXM1.8D, 16D
(BI Default)
Shorting the input
ON
TXM1.8U (-ML), TXM1.8X (-ML) (UIO Default)
No voltage
(input open or shorted)
OFF
–75 ... +75 µA at input OFF
High-resistance conduc-
tivity tester
 Do not use!
>75 µA at input ON
Correct polarity of
low-resistance conduc-
tivity tester (buzzer)
< –75 µA at input Flashing 1 Hz
Incorrect polarity of
low-resistance conduc-
tivity tester (buzzer)
>11.5 V at input Flashing 1 Hz
E.g. DC24 V connected
by mistake
AC24 V at input Flashing 1 Hz
AC24 V connected by
mistake
TXM1.8P (RI Default)
< 40 Ohms on input
ON
(no LCD)
Especially short circuit
> 40 Ohms on input
OFF
(no LCD)
Testing digital
TXM1.6R (-M), TXM1.6RL, TXM1.8T (BO Default)
outputs
Local override or tool
override enabled
ON / OFF
The module executes all local overrides
(local override, tool override)directly,
without safety precautions or interlocks.
 Special care is required 
TXM1.8RB (4 x MO Steps (2-stage) / Q-M2)
Tool override enabled
OFF / Stage 1 / Stage 2
Testing analog
outputs
TXM1.8U (-ML),
TXM1.8X (-ML)
UIO Default is an input function. For safety reasons, planned
analog outputs can not be tested with unconfigured modules. As
soon as the modules are configured, you can use the functional
tests described in CM110561.