Where to Ground the Service
The incoming neutral conductor of a utility company’s service entrance is grounded at the pole or pad-mount transformer. Once at the residence, this neutral is once again bonded to ground at the first means of over-current protection in the main disconnect.
The neutral (white) should not touch the ground (bare or green) anywhere in the house except here at the main disconnect. This is a safety feature that provides a separate path to ground from the neutral conductor. The ground wires of the individual branch circuits are all connected into the same grounding bar in the main panel. The ground wires carry the ground to each and every device, fixture, and appliance in the house.
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