Siemens SIMATIC S7-1500 Manual page 21

Connection: Thermocouples for external/internal compensation
The figure below shows an example of the pin assignment for thermocouples for external or
internal compensation.
①
Wiring of a thermocouple for internal compensation
②
Wiring of a thermocouple for external compensation
③
Analog digital converter
④
Backplane bus interface
⑤
Supply voltage via power supply element
⑥
Equipotential bonding cable (optional)
Figure 3-7 Block diagram and pin assignment for the thermocouple
Analog Input Module AI 4xU/I/RTD/TC ST (6ES7531-7QD00-0AB0)
Manual, 09/2016, A5E32366209-AC
3.1 Wiring and block diagrams
CHx Channel or 4 x channel status (green/red)
RUN Status display LED (green)
ERROR Error display LED (red)
PWR LED for power supply (green)
Wiring
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