Grounding Concept - Siemens SINUMERIK 840D sl Manual

Application Planning
3.1 Secondary electrical conditions
3.1.2

Grounding concept

Components
The SINUMERIK 840D sl system consists of a number of individual components which have
been designed so that the system complies with the appropriate EMC and safety standards.
The individual system components are:
● Numerical Control Unit (NCU)
● Machine Control Panel MCP, Machine Push Button Panel MPP
● Keyboard
● Operator panels (operator panel front + TCU/PCU)
● Distributor box and handheld unit
● S7-300 I/O with IM 153 interface module
Grounding measures
The individual modules are attached to a metal cabinet panel by means of screws. Make
sure that near the screws a low-impedance contact of the Control Unit with the cabinet panel
can be made. Insulating paints at the contact point must be removed. The electronics unit
grounds of the modules are connected to each other via DRIVE-CLiQ.
It is permissible to have a cluster of operator components for ground connection/PA.
Example: The control panel on the swivel arm.
It is sufficient in this instance to connect the ground connections of, for example, the PCU,
TCU, and operator panel front using a cable and to route a shared grounding conductor to
the central ground connection in the control cabinet.
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Manual, 03/2010, 6FC5397-0AP10-3BA0
NCU