Siemens SIPLUS HCS Series Operating Instructions Manual page 74

Connecting
6.2 Connecting the protective conductor
Connecting a protective conductor to the rack
Risk of electric shock
The rear panel on which the rack is mounted must be metallically conductive and grounded.
If this is not the case, you must ground the frame for a second time at a mounting hole.
If the rear panel is not metallically conductive and not grounded, the leakage current may
be too high and there is a risk of danger to life.
Connect the rack to the protective conductor (PE). You will find an M6 threaded bolt on the
right side of the rack for this purpose
lock washer) are attached to the threaded bolt in the delivery condition.
72
WARNING
①
. The retaining elements (nut, washer and spring
SIPLUS HCS4200 PROFINET/PROFIBUS DP
Operating Instructions, 07/2019, A5E35066204A/006