Licensed Electrical Contractor Services, Feeders, and Branch Circuits 3

Question 1

What is the minimum burial depth for a service lateral installed in rigid metal conduit (RMC) under a residential driveway?

Accepted Answer

12 inches

Answer

NEC Table 300.5 requires RMC installed under a residential driveway to be buried a minimum of 12 inches.

Question 2

When calculating feeder loads for a commercial occupancy with 30 or more receptacles, NEC 220.44 allows a demand factor for receptacles above 10 kVA of:

Accepted Answer

50%

Answer

NEC 220.44 allows a 50% demand factor on receptacle loads exceeding 10 kVA in non-dwelling occupancies.

Question 3

Service-entrance cable (Type SE) used as interior wiring must comply with the requirements of:

Accepted Answer

Article 338 and applicable wiring method articles

Answer

NEC 338.10(B) states that SE cable used as interior wiring must comply with Article 338 and the applicable portions of Article 334.

Question 4

Per NEC 230.54, service-entrance conductors in a raceway must be protected from water entering the raceway at the service head by:

Accepted Answer

Conductors formed in a drip loop

Answer

NEC 230.54(F) requires conductors to be arranged in a drip loop to prevent water from entering the raceway.

Question 5

The minimum size copper grounded conductor for a 400-ampere service with 500 kcmil copper ungrounded conductors is:

Accepted Answer

1/0 AWG

Answer

Per NEC Table 250.102(C)(1), 500 kcmil ungrounded conductors require a minimum 1/0 AWG copper grounded (neutral) conductor.

Licensed Electrical Contractor Practice Test

Licensed Electrical Contractor Practice Test

Licensed Electrical Contractor Services, Feeders, and Branch Circuits 3