Switchable Wire Break Check - Siemens 181 Workshop Manual

A.3

Switchable wire break check

Function
The "Switchable wire break check" is available for thermocouples. It switches off the wire
break check for the module.
This is required, for example, to calibrate thermocouples, since the test current necessary for
a wire break check leads to measurement errors during calibration.
The function has no effect on channels that are not assigned in the thermocouple mode.
Note
Startup and parameter reassignment
The wire break check is switched on again at each startup and during any parameter
reassignment of the module.
Switch-off via the user program
You can deactivate the wire break check using data record 237.
Table A- 12
Byte
0
1
2
3
4
5
6
7...17
Analog input module AI 4xRTD/TC 2-/3-/4-wire HF (6ES7134-6JD00-0CA1)
Manual, 02/2014, A5E03573289-AD
Structure of data record 237, switchable wire break check
Function Format
Command UBYTE
Identifier UBYTE
Channel number UBYTE
Calibration step UBYTE
Measurement type UBYTE
Measuring range UBYTE
Action UBYTE
Reserved UBYTE
A.3 Switchable wire break check
Value Description
80 Wire break check
H
00 Not relevant
H
FF All channels
H
FF First triggering
H
00 Not relevant
H
00 Not relevant
H
01 Deactivate wire break check
H
02 Activate wire break check
H
00 Not relevant
H
Parameter data record
61