Licensed Electrical Contractor FREE Licensed Electrical Contractor Special Occupancies and Equipment Questions and Answers 3

Question 1

Per NEC Article 680, what is the minimum burial depth for a direct-buried cable supplying a pool pump motor when not under a building or concrete?

Accepted Answer

18 inches

Answer

6 inches

Answer

12 inches

Answer

24 inches

Question 2

In a Class II, Division 1 hazardous location containing combustible dust, which of the following enclosure types is required for electrical equipment?

Accepted Answer

Dust-ignitionproof enclosure

Answer

Weatherproof enclosure

Answer

Raintight enclosure

Answer

General-purpose enclosure

Question 3

What is the required working space depth in front of electrical equipment rated 277 volts to ground with exposed live parts on one side and grounded parts on the other per NEC Table 110.26(A)(1)?

Accepted Answer

3.5 feet

Answer

3 feet

Answer

4 feet

Answer

4.5 feet

Question 4

Per NEC Article 511, above what height in a commercial repair garage are Class I, Division 2 requirements no longer applicable?

Accepted Answer

18 inches above floor

Answer

12 inches above floor

Answer

48 inches above floor

Answer

The entire area up to the ceiling is classified

Question 5

What bonding requirement does NEC Article 680 impose on metal parts of a pool structure, including reinforcing steel?

Accepted Answer

All metal parts must be bonded together with a minimum 8 AWG copper conductor

Answer

Bonding is optional if equipment is GFCI protected

Answer

Only underwater metal parts require bonding

Answer

Bonding is only required for saltwater pools

Question 6

In an assembly occupancy with more than 100 persons, what does NEC Article 518 require regarding the wiring methods used?

Accepted Answer

Wiring must be installed in metal raceways, nonmetallic raceways in concrete, Type MC or AC cable

Answer

Only Type NM cable is permitted

Answer

Any wiring method approved for general use is permitted

Answer

Only rigid metal conduit is allowed