Services & DistributionQuestion 64 of 521
Overload protection for service-entrance conductors must be provided by an overcurrent device in series with:
a.The grounded conductor only
b.Each ungrounded service conductor
c.The grounding electrode conductor
d.The equipment grounding conductor
Explanation
Per 230.90(A), each ungrounded service-entrance conductor must have overload protection, generally an overcurrent device rated not more than the conductor ampacity. The grounded (neutral) conductor is not fused this way, and grounding/grounding-electrode conductors never carry service overcurrent devices.
Law Reference: 2023 NEC §230.90Practice all 521 questions free — no signup required.
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- A service supplies a continuous load of 80 A and a noncontinuous load of 100 A. What is the minimum required ampacity of the service-entrance conductors?
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