COMPLETE EXAM QUESTIONS AND VERIFIED ANSWERS |
2026–2027 LATEST UPDATE | GUARANTEED PASS | DETAILED
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Section One — Questions 1–100
1. A 20-ampere, 120-volt branch circuit supplies receptacles in a commercial building. What is the
minimum copper conductor size permitted?
A) 14 AWG
B) 12 AWG
C) 10 AWG
D) 8 AWG
Correct Answer: B) 12 AWG
Rationale: NEC Table 310.16 requires a minimum of 12 AWG copper conductors for a 20-ampere
branch circuit. 14 AWG is only permitted for 15-ampere circuits. This sizing ensures the conductor can
carry the circuit's rated current without overheating and complies with the general requirements for
branch circuit conductor ampacity.
2. What is the required free space volume allowance for a single 14 AWG conductor in a junction
box?
A) 1.50 cubic inches
B) 2.00 cubic inches
C) 2.25 cubic inches
D) 2.50 cubic inches
Correct Answer: B) 2.00 cubic inches
Rationale: NEC Table 314.16(B) specifies the volume allowance per conductor. A 14 AWG conductor
requires 2.00 cubic inches, while a 12 AWG conductor requires 2.25 cubic inches. This information is
critical for performing box fill calculations to ensure junction boxes are not overfilled, which is a
common code violation.
3. For a dwelling unit, the required general lighting load is based on a unit load of _____ volt-
amperes per square foot.
A) 2 VA
B) 3 VA
C) 4 VA
D) 5 VA
Correct Answer: B) 3 VA
,Rationale: NEC Table 220.12 specifies the general lighting load for dwelling units as 3 VA per square
foot. This is the baseline figure used for service and feeder load calculations. The other values apply
to different occupancy types, such as hospitals (2 VA) or banks (5 VA).
4. According to Article 100, a "continuous load" is a load where the maximum current is expected
to continue for _____ or more.
A) 1 hour
B) 2 hours
C) 3 hours
D) 4 hours
Correct Answer: C) 3 hours
Rationale: The NEC defines a continuous load as one where the maximum current is expected to
continue for 3 hours or more. This definition triggers special rules, such as sizing branch circuit
conductors at 125% of the continuous load and requiring circuit breakers to be rated for continuous
use at 80% of their rating.
5. The frame of a portable generator that is cord-and-plug connected to a transfer switch shall be
grounded by which method?
A) A driven ground rod at the generator location
B) The equipment grounding conductor in the cord
C) Bonding the frame to the transfer switch enclosure
D) Connection to the building grounding electrode system
Correct Answer: B) The equipment grounding conductor in the cord
Rationale: The generator frame is grounded through the equipment grounding conductor in the
supply cord, which connects to the grounded system at the building's service. Additional ground rods
are not required and can create a hazard. This complies with NEC 250.34, which covers the grounding
of portable and vehicle-mounted generators.
6. A service technician is determining the minimum lighting load for a 2,000 sq. ft. dwelling unit.
What is the total calculated general lighting load before any demand factors are applied?
A) 4,000 VA
B) 5,000 VA
C) 6,000 VA
D) 8,000 VA
Correct Answer: C) 6,000 VA
Rationale: The calculation uses the unit load of 3 VA per square foot from NEC Table 220.12.
Therefore, 2,000 sq. ft. multiplied by 3 VA equals 6,000 VA. This is the first step in calculating the
service size for a dwelling unit before applying demand factors from NEC Table 220.42.
7. What is the maximum distance between supports for horizontal runs of 1-inch rigid metal
conduit (RMC)?
A) 10 feet
B) 12 feet
, C) 14 feet
D) 20 feet
Correct Answer: C) 14 feet
Rationale: NEC Table 344.30(B)(2) specifies the maximum spacing for RMC supports. For a 1-inch
trade size, the maximum distance between supports is 14 feet. The spacing increases with the size of
the conduit, but for smaller conduits, it requires more frequent support to prevent sagging and
mechanical stress on the conduit and conductors.
8. Which of the following devices must be GFCI-protected in a residential kitchen?
A) Refrigerator receptacle
B) Dishwasher hard-wired connection
C) Countertop receptacles within 6 feet of a sink
D) Range receptacle
Correct Answer: C) Countertop receptacles within 6 feet of a sink
Rationale: NEC 210.8(A)(6) requires GFCI protection for all 125-volt, 15- and 20-ampere receptacles
that serve kitchen countertop surfaces. The code specifies these must be within 6 feet of the sink.
Receptacles for refrigerators and ranges are generally exempt from this requirement.
9. What is the primary purpose of a bonding jumper?
A) To provide a path for normal operating current
B) To establish a low-impedance path for fault current
C) To connect the service neutral to the grounding electrode
D) To increase the resistance of the grounding path
Correct Answer: B) To establish a low-impedance path for fault current
Rationale: A bonding jumper connects metal parts to ensure electrical continuity and provide a low-
impedance path for fault current. This allows circuit breakers or fuses to open quickly during a ground
fault. It is distinct from the grounding electrode conductor, which connects the system to the earth.
10. Which type of conduit is permitted for use in wet locations?
A) Electrical Metallic Tubing (EMT)
B) Intermediate Metal Conduit (IMC)
C) Rigid Metal Conduit (RMC)
D) All of the above
Correct Answer: D) All of the above
Rationale: All three—EMT, IMC, and RMC—are permitted in wet locations under the NEC, provided
they are listed and installed with appropriate fittings and corrosion protection. This includes materials
like galvanized steel or aluminum, which are resistant to corrosion in damp or wet environments.
11. When installing NM-B cable in a wall cavity, the cable must be protected by a metal plate if it is
within what distance of the edge of a stud?
A) 1 inch
B) 1 1/4 inches