FREE NEC Code Questions and Answers

Question 1

A set of 450 kcmil feeder conductors is protected by a 400 breaker. 
With a 25 A over current device, a feeder fed from a 450 kcmil feeder
 disconnects. What is the smallest conductor size for these taps?

Accepted Answer

8 AWG

Answer

4 AWG

Answer

16 AWG

Answer

6 AWG

Question 2

For a 4in * 4 in wireway, what is the maximum permitted conductor fill?

Accepted Answer

3.2 sq in

Answer

4.8 sq in

Answer

16 sq in

Answer

8 sq in

Question 3

For a 4000 W, 240 electric water heater, what size branch circuit conductor is required?

Accepted Answer

10 AWG

Answer

14 AWG

Answer

12 AWG

Answer

8 AWG

Question 4

What is the general lighting load of a hospital with an area of 80,000 sq ft after the demand factor is applied?

Accepted Answer

42,000 VA

Answer

1,60,000 VA

Answer

82, 000 VA

Answer

58,000 VA

Question 5

For a dwelling unit with a calculated load of 240 A, what size feeder conductors 
are required? The feeder conductors carry the whole load of the dwelling unit, 
and the service disconnect is rated for 250 A?

Accepted Answer

4/0 AWG

Answer

2/0 AWG

Answer

1/0 AWG

Answer

3/0 AWG

Question 6

For a constant load of 22 amperes at 750C, what size conductor should be used to protect against overcurrent?

Accepted Answer

10 THWN

Answer

12 THWN

Answer

8 THWN

Answer

16 THWN

Question 7

What is the needed conductor size for GEC if a service is fed by three parallel sets of 400 kcmil conductors?

Accepted Answer

3/0 AWG

Answer

2 AWG

Answer

2/0 AWG

Answer

4 AWG

Question 8

In a 4 in. * 4 in. wireway, how many 500 kcmil THWN conductors can be installed?

Accepted Answer

4 conductors

Answer

5 conductors

Answer

6 conductors

Answer

7 conductors

Question 9

A 45 KVA three phase transformer with a 115/230 delta configuration. 
What is the transformer secondary's high-leg voltage?

Accepted Answer

199 volts

Answer

230 volts

Answer

208 volts

Answer

399 volts

Question 10

Under a pool or within _____ horizontally of the inside wall of a pool, underground wiring is not allowed:

Accepted Answer

5 ft

Answer

3 ft

Answer

4 ft

Answer

6 ft