Siemens SIMATIC RF185C Operating Instructions Manual page 32

Connection
5.3 Connect CM to functional ground (PE)
Mounting
Proceed as follows to connect the communications module to functional ground via a
conductive mounting base:
1. Drill 2 mounting holes with a distance of 155.6 mm.
2. Screw the module together with the M4 fastening screws with a torque of 1.2 Nm.
NOTICE
Grounding with a conductive mounting base
If you fasten the communications module to a conductive, grounded base, the lower
fastening screw provides a conductive connection to the ground potential.
Ensure there is a low-impedance connection between the communications module and the
conductive base and between the conductive base and functional ground.
①
②
Figure 5-7
32
Grounded, metallic base
Unpainted thread or nut support
Mounting the CM on a conductive base
SIMATIC RF185C, RF186C, RF188C
Operating Instructions, 10/2018, C79000-G8976-C512-01