Connection According To The System-Side Grounding Concept; Connecting External Cables To The Pe Busbar - Siemens SINAMICS S120 Manual

4.6.3.3

Connection according to the system-side grounding concept

Danger to life when live parts are touched
If there is no connection to the central grounding of the complete plant, the cabinet unit may
be subjected to dangerous voltage in a fault situation.
Once you have established the connections to the PE busbar in the cabinet and/or
established the connections to the PE busbar across more than one cabinet unit, you must
establish a connection to the central ground of the entire system.
4.6.3.4

Connecting external cables to the PE busbar

NOTICE
It must be ensured that the cabinet doors are closed
When external cables that are to be connected to the PE busbar have been laid, make sure
that the cabinet doors close properly!
Preparatory steps
● Install and secure the cabinet units properly.
● Make sure that all the necessary safety measures have been taken at the installation
● Observe the "five safety rules".
● Allow unimpeded access to the PE busbar of the cabinet units (if necessary, remove the
Establishing the connection
1. Insert the screw from the front.
2. Attach the cable lug from behind.
3. Attach the nuts and, if necessary, the washers and tighten
Cabinet Modules
Manual, 03/2013, A5E03263538A
WARNING
location.
protective covers during installation work).
(torque: 50 Nm).
Electrical installation
4.6 Connections
77