F80 Code Requirements 5 — Questions and Answers
Question 1: According to the NEC, what is the maximum voltage permitted between conductors for receptacles installed in dwelling unit bedrooms?
- 120 volts
- 150 volts
- 250 volts (Correct answer)
- No voltage limit applies to bedrooms
Correct answer: 250 volts
The NEC does not restrict receptacle voltage in bedrooms to 120 volts; standard 250-volt receptacles are permitted for appliances such as window air conditioners.
Question 2: Under NEC 300.14, at least how much free conductor length must be left at each outlet, junction, or switch point for splices or connections?
- 4 inches
- 6 inches (Correct answer)
- 8 inches
- 12 inches
Correct answer: 6 inches
NEC 300.14 requires a minimum of 6 inches of free conductor length, measured from the point it emerges from the raceway or cable sheath.
Question 3: Per NEC 250.119, which color is reserved exclusively for equipment grounding conductors when conductors are 6 AWG or smaller?
- White
- Gray
- Green (Correct answer)
- Bare copper only
Correct answer: Green
NEC 250.119 designates green or green with yellow stripes as the identification for equipment grounding conductors 6 AWG and smaller.
Question 4: What does the NEC require regarding arc-fault circuit interrupter (AFCI) protection in a newly constructed single-family dwelling?
- AFCI protection is required for kitchen circuits only
- AFCI protection is required for all 120-volt, 15- and 20-ampere branch circuits in all rooms (Correct answer)
- AFCI protection is required only for bedroom circuits
- AFCI protection is optional in single-family dwellings
Correct answer: AFCI protection is required for all 120-volt, 15- and 20-ampere branch circuits in all rooms
NEC 210.12(A) now requires combination-type AFCI protection for all 120-volt, 15- and 20-ampere branch circuits throughout dwelling units.
Question 5: Under NEC 230.70, where must the service disconnecting means be installed?
- At the meter base
- Inside the building at the point of entry
- At a readily accessible location either outside or inside nearest the point of entrance (Correct answer)
- In the main electrical room only
Correct answer: At a readily accessible location either outside or inside nearest the point of entrance
NEC 230.70(A)(1) requires the service disconnecting means to be installed at a readily accessible location either outside or inside the building, nearest the point of service entrance.
Question 6: According to NEC 410.10(D), luminaires installed in or over a bathtub or shower zone must be listed for what environment?
- Damp locations
- Wet locations (Correct answer)
- Intrinsically safe locations
- Explosion-proof locations
Correct answer: Wet locations
NEC 410.10(D) requires luminaires installed within the bathtub or shower zone to be listed for wet locations.
Question 7: Per NEC 210.52(C), how many small-appliance branch circuits must be provided for the kitchen receptacles in a dwelling unit?
- At least one 20-ampere circuit
- At least two 20-ampere circuits (Correct answer)
- At least one 15-ampere and one 20-ampere circuit
- At least three 20-ampere circuits
Correct answer: At least two 20-ampere circuits
NEC 210.52(C)(1) requires a minimum of two 20-ampere small-appliance branch circuits to serve kitchen countertop receptacles.
According to the NEC, what is the maximum voltage permitted between conductors for receptacles installed in dwelling unit bedrooms?