NEC Electrical 2 — Questions and Answers
Question 1: What is the minimum size copper grounding electrode conductor required for a service with 200-amp THHN copper conductors?
- #8 AWG
- #6 AWG
- #4 AWG (Correct answer)
- #2 AWG
Correct answer: #4 AWG
Per NEC Table 250.66, a 200-amp service requires a minimum #4 AWG copper grounding electrode conductor.
Question 2: What is the maximum number of 12 AWG THHN conductors permitted in a 1/2-inch EMT conduit?
- 6
- 8
- 9 (Correct answer)
- 12
Correct answer: 9
NEC Chapter 9 fill tables allow 9 of the 12 AWG THHN conductors in 1/2-inch EMT at 40% fill.
Question 3: In a dwelling, receptacles installed within 6 feet of a wet bar sink must be protected by what device?
- AFCI
- GFCI (Correct answer)
- Surge protector
- TVSS
Correct answer: GFCI
NEC 210.8 requires GFCI protection for receptacles near sinks to protect against ground faults.
Question 4: What is the standard mounting height (to center) for a wall switch in a typical dwelling?
- 36 inches
- 44 inches
- 48 inches (Correct answer)
- 54 inches
Correct answer: 48 inches
Switches are commonly mounted at 48 inches to center, though the NEC does not mandate a fixed height.
Question 5: Which color is required for the grounded (neutral) conductor in systems of 120/240 volts?
- Green
- White or gray (Correct answer)
- Red
- Black
Correct answer: White or gray
NEC 200.6 requires the grounded conductor to be white or gray for sizes 6 AWG and smaller.
Question 6: What is the maximum overcurrent protection allowed for a 14 AWG copper conductor?
- 10 amps
- 15 amps (Correct answer)
- 20 amps
- 30 amps
Correct answer: 15 amps
NEC 240.4(D) limits 14 AWG copper to a 15-amp overcurrent device.
Question 7: How many small-appliance branch circuits are required minimum in a dwelling kitchen?
- 1
- 2 (Correct answer)
- 3
- 4
Correct answer: 2
NEC 210.11(C)(1) requires at least two 20-amp small-appliance branch circuits for kitchen countertop receptacles.
NEC Electrical 2
What is the minimum size copper grounding electrode conductor required for a service with 200-amp THHN copper conductors?