Siemens NXPLUS C Installation And Operating Instructions Manual page 161

Installation
➭ Connect the cable shield and the earthing of the plug housing to the cable bracket.
➭ Option: Mount the insulated earthing bar ① onto the cable bracket.
The use of an insulated earthing bar ① makes the connection of the cable shields to the zero-
sequence current transformer easier. All cable shields are connected to the insulated earthing
bar. An earthing cable ② leads from the earthing bar into the cable basement to the zero-
sequence current transformer. The zero-sequence current transformer earths all cable shields
through its own electric cable and leads them back. Without the use of the insulated busbar,
each individual cable shield must be led to the zero-sequence current transformer and
earthed.
Fig. 120: Basic scheme
802-9081.9 • INSTALLATION AND OPERATING INSTRUCTIONS • NXPLUS C • Revision 11 161/293