Which of the following installations does not require ground fault protection of equipment?
A. Branch circuit disconnect rated 1,200A, 480V/277V, 3-phase, 4-wire, in an industrial building where this branch circuit is supplying equipment that is not part of a continuous industrial process where a non-orderly shutdown will introduce additional hazards.
B. Branch circuit disconnect rated 1,200A, 480V/277V, 3-phase, 4-wire, for equipment that is part of a continuous industrial process where a non-orderly shutdown will introduce additional or increased hazards.
C. A service disconnect rated 4,000A, 480V/277V, 3-phase, 4-wire, in a commercial building where a non-orderly shutdown will not introduce additional or increased hazards.
D. A feeder disconnect rated 2,000A, 480V/277V, 3-phase, 4-wire, in an industrial building where this feeder circuit is supplying equipment that is not part of a continuous industrial process where a non-orderly shutdown will introduce additional or increased hazards.
Find the Answer
Answer: B
A change in the 2014 edition of the NEC now requires ground fault protection of equipment for branch circuit disconnects rated 1,000A or more, at greater than 150V to ground, and not exceeding 600V phase-to-phase on solidly grounded systems. This new section of the NEC also has two exceptions, as does Sec. 215.10—and the same exception as included in Sec. 230.95.
Owen is the owner and president of National Code Seminars and the holder of master electrician certifications in 46 states. He can be reached at [email protected].