Siemens SIMATIC ET 200MP Manual page 15

Wiring
Block diagram and pin assignment for voltage measurement
The example in the following figure shows the pin assignment for voltage measurement.
①
Analog-to-digital converter (ADC)
②
Backplane bus interface
③
Infeed element (for shielding only)
④
Equipotential bonding cable (optional)
Figure 3-2 Block diagram and pin assignment for voltage measurement
14
CHx Channel or 8 x channel status (green/red)
RUN Status display LED (green)
ERROR Error display LED (red)
Analog Input Module AI 8xU/I/R/RTD BA (6ES7531-7QF00-0AB0)
Manual, 03/2019, A5E44792324-AA