Siemens SIMATIC S7-1500/ET 200MP Manual page 12

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
Analog input module AI 16xU BA (6ES7531-7LH00-0AB0)
Equipment Manual, 09/2020, A5E47052556-AA
CHx Channel or 16 x channel status (green/red)
RUN Status display LED (green)
ERROR Error display LED (red)
Wiring
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