Licensed Electrical Contractor NEC Code Requirements 2 — Questions and Answers
Question 1: According to the NEC, the maximum number of conductors allowed in a junction box is determined by:
- The electrician's preference
- Box fill calculations based on box volume and conductor sizes (Correct answer)
- Always a maximum of 6 conductors
- The color of the wires
Correct answer: Box fill calculations based on box volume and conductor sizes
NEC Article 314.16 requires box fill calculations to determine maximum conductors.
NEC 314.16 specifies that each conductor, clamp, device, and equipment grounding conductor takes up a specific volume in cubic inches. The total cannot exceed the box volume. For example, a #14 AWG wire counts as 2 cubic inches.
Question 2: The NEC requires GFCI protection for 125V, 15- and 20-amp receptacles in:
- Bedrooms only
- Bathrooms, kitchens within 6 feet of sink, and outdoors (Correct answer)
- Only commercial buildings
- All rooms in a house
Correct answer: Bathrooms, kitchens within 6 feet of sink, and outdoors
NEC 210.8 requires GFCI protection in wet/damp locations including bathrooms, kitchens near sinks, and outdoors.
NEC 210.8 mandates GFCI protection in bathrooms, kitchens (within 6 ft of sink edge), outdoors, garages, crawl spaces, unfinished basements, laundry areas, and other locations where water contact is likely.
Question 3: The NEC defines a 'qualified person' as someone who:
- Has a driver's license
- Has skills and knowledge related to electrical equipment and has received safety training (Correct answer)
- Has been an electrician for 1 year
- Owns their own tools
Correct answer: Has skills and knowledge related to electrical equipment and has received safety training
NEC Article 100 defines qualified person based on skills, knowledge, and safety training.
Per NEC Article 100, a 'qualified person' has demonstrated skills and knowledge related to the construction and operation of electrical equipment and installations, and has received safety training to recognize and avoid associated hazards.
Question 4: The minimum height for a residential electrical panel is:
- 3 feet from floor
- No minimum, can be at floor level
- The working space must allow access to all breakers up to 6'7" maximum (Correct answer)
- 10 feet from floor
Correct answer: The working space must allow access to all breakers up to 6'7" maximum
NEC 240.24(A) requires panels be readily accessible, with no breaker handle above 6'7".
NEC 240.24(A) states overcurrent devices must be readily accessible. NEC 404.8(A) requires the center of the grip of the operating handle in its highest position to be no more than 6 feet 7 inches above the floor or working platform.
Question 5: Per the NEC, the minimum burial depth for direct-buried UF cable in a residential yard is:
- 6 inches
- 12 inches
- 24 inches (Correct answer)
- 36 inches
Correct answer: 24 inches
NEC Table 300.5 requires 24 inches minimum burial depth for direct-buried cables (non-GFCI).
NEC Table 300.5 specifies minimum cover requirements. Direct-buried UF cable requires 24 inches of cover for 120V circuits. This can be reduced to 12 inches if GFCI-protected and marked, or if installed under concrete.
Question 6: The NEC requires a minimum of how many 20-amp small appliance circuits in a 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 in kitchens.
NEC 210.11(C)(1) requires a minimum of two 20-amp small appliance branch circuits to serve kitchen, pantry, breakfast room, dining room, and similar areas. These circuits cannot supply lighting or other outlets outside these areas.
Licensed Electrical Contractor NEC Code Requirements 2
According to the NEC, the maximum number of conductors allowed in a junction box is determined by: