Services & DistributionQuestion 109 of 521
A detached garage is supplied by a feeder from the main dwelling. At the garage, the code generally requires:
a.No grounding electrode because the feeder has an equipment grounding conductor
b.The neutral must be bonded to the enclosure like at a service
c.A grounding electrode (or electrode system) to be installed and connected to the building disconnect, with the equipment grounding conductor run with the feeder
d.Only a single ground rod with the neutral used as the ground
Explanation
Per 250.32, a building or structure supplied by a feeder must have a grounding electrode connected to the equipment grounding terminal at the disconnect, and an equipment grounding conductor must be run with the feeder while the neutral remains isolated. Re-bonding the neutral downstream (the old exception) is no longer generally permitted.
Law Reference: 2023 NEC §250.32Practice all 521 questions free — no signup required.
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