Earthing - Siemens 3AH3 Operating Instructions Manual

Connecting to earth
Fig. 62 Earth terminal
Connect low-voltage
Siemens Parts
9229 9860 176 0E
2013-08-22

Earthing

Connect the vacuum circuit-breaker on the earth terminal (70.) to the high-voltage
protective earth as specified (DIN EN 50341).
• Fully unscrew hexagon socket head screw M12 with washer on the earth termi-
nal (70.).
• Tighten ring terminal for the earth wire with the M12 hexagon screw and washer
on the earth terminal (70.) with 40 Nm.
Note
If the 3AH3 vacuum circuit-breaker is installed into an earthed metal frame and is
connected permanently and electrically conductive, no separate earthing is
required.
Place serrated washers under the screw heads when fastening the vacuum cir-
cuit-breaker in this case.
Connect the low-voltage connecting cables in the customer's switch cabinet in such
a way that safe operation as per supplied circuit diagram is guaranteed.
Fig. 63 Connecting earth wire
Mounting
45