Branch circuits and feeders in a separately derived 60-volts to ground system shall be provided with a means to ____.
A) prevent current surges
B) simultaneously disconnect all ungrounded conductors
C) protect from lightning discharges
D) permit service access

Question

Quizplus · Accepted Answer

According to NEC 250.30(A)(3), "a means shall be provided to simultaneously disconnect all ungrounded conductors in the event that the grounded conductor is opened or becomes disconnected from the equipment grounding conductor or from the grounding electrode conductor." This is necessary in a separately derived system to prevent the possibility of electrical shock or equipment damage. Options A, C, and D do not directly relate to the requirement stated in the question.

Branch Circuits and Feeders in a Separately Derived 60-Volts to Ground