11/05/2025
Grounding of Services by Mike Holt, NEC Consultant
Correct grounding of services depends upon understanding the definition and role of the grounded conductor. The grounded conductor is typically the neutral, so going forward we will refer to the grounded conductor as the neutral.
Grounding electrode connection
A premises wiring system supplied by a grounded service must have a grounding electrode conductor connected to the service neutral conductor as follows:
(1) General. The grounding electrode conductor connection to the neutral conductor at the service must be made at any accessible point from the load end of the overhead service conductors, service drop, underground service conductors, or service lateral to the terminal or bus to which the service neutral conductor is connected at the service disconnect.
Some inspectors require the grounding electrode conductor connection to the service neutral conductor to be made at the meter socket enclosure, while others insist the connection be made only within the service disconnect. Grounding at either location complies with this rule, but be sure you know the local utility company’s policy on connections inside the meter socket.
(4) Service Equipment, Main Bonding Jumper. If the main bonding jumper specified in 250.28 is a wire or busbar, you can terminate the grounding electrode conductor to the equipment grounding terminal, bar, or bus to which the main bonding jumper is connected, instead of to the neutral terminal.
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