Siemens SIMATIC S7-1500 Manual page 55

Structure of data record 8, reference channel (COMP) of the module
The reference channel compensates the measured value for channels 0 to 7. The figure
below shows the structure of data record 8. Enable a parameter by setting the corresponding
bit to "1".
Figure B-3
Analog input module AI 8xU/I/RTD/TC ST (6ES7531-7KF00-0AB0)
Manual, 09/2016, A5E03484864-AD
B.1 Parameter assignment and structure of the parameter data records
Structure of data record 8, reference channel of the module: Bytes 0 to 27
Parameter data records
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