Overcurrent Protection & Grounding Flashcards

Under NEC 250.32(B), a separate structure served by a feeder or branch circuit must have which of the following at the disconnecting means?

Answer: An equipment grounding conductor run with the circuit conductors

NEC 250.32(B) requires an EGC run with the feeder to a separate structure rather than a neutral-to-ground bond at the remote panel (with limited exceptions).

What is the standard ampere rating immediately above 35 amperes per NEC 240.6(A)?

Answer: 40 amperes

NEC 240.6(A) lists standard ampere ratings; the next standard size above 35A is 40A.

Per NEC 250.118, which wiring method is NOT recognized as an equipment grounding conductor?

Answer: Flexible metal conduit (FMC) over 6 feet in length

NEC 250.118(5) permits FMC as an EGC only in lengths not exceeding 6 feet; longer runs require a separate EGC wire.

When a circuit breaker is used as a switch for 120V fluorescent lighting, NEC 240.83(D) requires the breaker to be:

Answer: Marked 'SWD' or 'HID'

NEC 240.83(D) requires breakers used as switches for fluorescent lighting to be listed and marked 'SWD' (switching duty).

What minimum burial depth is required for a ground rod electrode under NEC 250.53(G)?

Answer: 8 feet

NEC 250.53(G) requires ground rods to be driven to a depth of at least 8 feet into the earth.

According to NEC 230.95, ground-fault protection of equipment (GFPE) is required for solidly grounded wye services of more than 150 volts to ground but not exceeding 600 volts phase-to-phase, and rated:

Answer: 1000 amperes or more

NEC 230.95 mandates GFPE for services rated 1000 amperes or more on the specified system voltage range.

Under NEC 250.130(C), when replacing a non-grounding type receptacle, which is a permitted method to provide grounding?

Answer: Both B and C are permitted

NEC 250.130(C) allows grounding via a new EGC to the panel, to any accessible grounded point, or by using a GFCI device labeled 'No Equipment Ground.'