Siemens SCALANCE MUM853-1 Operating Instructions Manual page 46

Connection
6.1 Safety when connecting up
Note
Protective ground
A PELV circuit contains a connection to protective ground. Without a connection to protective
ground, or in case there is a fault in the connection to the protective ground, the voltage for the
circuit is not stabilized.
Note
Minimum temperature rating of the cable to be connected to the field wiring terminals, 90 °C.
Safety notices for operation with a power supply not complying with NEC Class 2
If you operate the device in a control cabinet, you can use a power supply that does not comply
with NEC Class 2. When connecting up the device, keep to the safety notices listed below.
Safety extra low voltage
The device is designed for operation with a directly connectable safety extra-low voltage (SELV)
according to UL/IEC 61010-1 and UL/IEC 61010-2-201 whose output power corresponds to
"Limited Energy" according to UL/IEC 61010-1.
46
WARNING
Operating Instructions, 03/2023, C79000-G8976-C650-05
SCALANCE MUM853-1