NEC Overcurrent Protection & Grounding 2

Question 1

According to NEC 240.4(D), what is the maximum overcurrent protection permitted for 14 AWG copper conductors?

Accepted Answer

15 amperes

Answer

NEC 240.4(D) limits overcurrent protection for 14 AWG copper to 15 amperes regardless of the conductor's ampacity.

Question 2

What NEC article governs the use of ground-fault circuit-interrupter (GFCI) protection?

Accepted Answer

Article 210

Answer

Article 210 covers branch circuits, including the GFCI protection requirements for receptacles in wet and damp locations.

Question 3

What is the minimum size copper equipment grounding conductor (EGC) required for a circuit protected by a 60-ampere overcurrent device per NEC Table 250.122?

Accepted Answer

10 AWG

Answer

NEC Table 250.122 requires a minimum 10 AWG copper EGC for circuits protected at 60 amperes.

Question 4

Under NEC 250.24(A), a service-entrance grounded conductor (neutral) must be connected to the grounding electrode system at which location?

Accepted Answer

At the service disconnecting means enclosure

Answer

NEC 250.24(A) requires the grounded conductor to be bonded to the grounding electrode system at the service disconnecting means.

Question 5

A 20-ampere, 120-volt branch circuit breaker trips repeatedly under normal load. Per NEC principles, what is the FIRST corrective action?

Accepted Answer

Evaluate the actual load versus the circuit's rated capacity

Answer

NEC requires conductors and overcurrent devices to be properly sized for the load; the load must be evaluated before upsizing protection.

NEC Practice Test

NEC Practice Test

NEC Overcurrent Protection & Grounding 2