Siemens SIMATIC Distributed I/O ET 200eco PN Operating Instructions Manual page 30

Configuring ET 200eco PN with grounded reference potential
In the configuration of the ET 200eco PN with grounded reference potential, any interference
currents that occur are discharged to functional ground. The terminals must be connected
externally (see the figure "Grounding concept for ET 200eco PN": Connection between 1M
and FE).
Configuring ET 200eco PN with ungrounded reference potential
In the configuration of the ET 200eco PN with ungrounded reference potential, any
interference currents that occur are discharged to functional ground via an internal RC
network (see in the figure "Grounding concept for ET 200eco PN": No connection between
1M and FE).
Insulation monitoring
Insulation monitoring must be provided in the following cases:
• When setting up the ET 200eco PN distributed I/O devices with non-grounded reference
potential
• If dangerous system states occur due to error
ET 200eco PN
Operating Instructions, 06/2022, A5E01250250-AN
3.2 Operating ET 200eco PN on grounded mains
Wiring
31