Connecting Cm To Functional Ground; Mounting The Cm On A Conductive Base - Siemens SIMATIC RF185C Operating Instructions Manual

5.4

Connecting CM to functional ground

You need to connect the RF18xC/RF18xCI communication module to functional ground. For
this purpose, a grounding screw for one ground conductor is provided on the communication
module.
If a grounded metal mounting surface is used, the bottom mounting screw of the
RF18xC/RF18xCI module already establishes a reliable ground connection. This eliminates the
need for a separate ground conductor.
This connection to functional ground is also required to discharge any interference currents
to ground and for EMI resistance.
Protection against external electrical influences
Below is a description of what you must pay attention to in terms of protection against
electrical impacts and/or faults:
• In all plants or systems in which the communication module is installed, you must ensure
that the plant or the system for dissipating electromagnetic interference is connected to
functional ground.
• For supply, signal and bus lines, you must ensure that the laying of the lines and the
installation is correct.
• For signal and bus lines, you must ensure that a wire/cable breakage or a cross-circuit does
not lead to undefined states of the plant or system.
5.4.1

Mounting the CM on a conductive base

Requirement
Conductive base for mounting the module.
Required tools
You need the following tool to connect to the functional ground:
• Screwdriver
Accessories required
You need the following accessories to connect to the functional ground:
• Fastening screw (M4) and washer
SIMATIC RF185C, RF186C, RF188C, RF186CI, RF188CI
Operating Instructions, 03/2022, C79000-G8976-C512-04
5.4 Connecting CM to functional ground
Connection
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