Siemens SIMATIC S7-1500 Manual page 20

Wiring
Connection: Non-grounded thermocouples for external/internal compensation and connection of a
resistance thermometer (RTD) at the reference channel
The following figure shows an example of the pin assignment of non-grounded
thermocouples for external/internal compensation and the connection of a resistance
thermometer (RTD) at the reference channel.
①
Wiring of a thermocouple (non-grounded) for internal
compensation
②
Wiring of a thermocouple (non-grounded) for external
compensation
③
Wiring of a resistance thermometer (RTD) at the
reference channel
④
Analog-to-digital converter (ADC)
⑤
Backplane bus interface
⑥
Supply voltage via power supply element
⑦
Equipotential bonding cable (optional)
Figure 3-6 Block diagram and pin assignment for non-grounded thermocouples and resistance thermometers
20
CHx Channel or 9 x channel status (green/red)
RUN Status display LED (green)
ERROR Error display LED (red)
PWR LED for power supply (green)
Analog input module AI 8xU/I/RTD/TC ST (6ES7531-7KF00-0AB0)
Manual, 09/2016, A5E03484864-AD