Grounding the switch with a grounding conductor buried in the
earth
If the installation site has no grounding strips but earth ground is available, hammer a 0.5 m (1.64 ft) or
longer angle iron or steel tube into the earth to serve as a grounding conductor.
Weld the yellow-green grounding cable to the angel iron or steel tube, and treat the joint for corrosion
protection.
Figure 20 Grounding the switch by burying the grounding conductor into the earth
(1) AC power receptacle
(5) Angle iron
Grounding the switch through the PE wire of an AC power cord
If the installation site has no grounding strips or earth ground, you must ground an AC-powered switch
through the protective earth (PE) wire of the power cord. Verify that the ground contact in the power outlet
is well connected to the ground in the power distribution room or on the AC transformer side.
1
(2) Grounding screw
(4) Earth
18
2
3
4
5
(3) Grounding cable