Questions and Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A | Instant
Download Pdf
1. Which NEC article covers the general requirements for grounding
and bonding?
A. Article 110
B. Article 250
C. Article 300
D. Article 430
Rationale: NEC Article 250 establishes the requirements for grounding
and bonding of electrical systems, equipment, and installations.
Proper grounding and bonding help stabilize system voltage, facilitate
operation of overcurrent devices during faults, and reduce shock
hazards.
2. What is the primary purpose of bonding electrical equipment?
,A. Increase voltage
B. Reduce conductor size
C. Provide an effective fault-current path
D. Prevent power outages
Rationale: Bonding electrically connects conductive parts together to
create a low-impedance path for fault current. This allows overcurrent
protective devices to operate quickly, minimizing the risk of electric
shock and fire.
3. According to the NEC, continuous loads must be calculated at
what percentage of their actual load?
A. 100%
B. 110%
C. 120%
D. 125%
Rationale: Continuous loads are those expected to operate for three
hours or more. NEC requires branch-circuit and feeder conductors, as
well as overcurrent protection, to be sized at not less than 125% of the
continuous load.
, 4. Which conductor is intentionally grounded in a typical single-
phase electrical system?
A. Equipment grounding conductor
B. Grounding electrode conductor
C. Grounded (neutral) conductor
D. Bonding jumper
Rationale: The grounded conductor, commonly called the neutral, is
intentionally connected to earth at the service equipment to establish
a reference to ground and facilitate system stability.
5. What is the minimum working space depth required for
equipment operating at 120/240 volts where conditions require
NEC Condition 2?
A. 2 feet
B. 3 feet 6 inches
C. 4 feet
D. 5 feet
Rationale: NEC Table 110.26(A)(1) specifies working space based on
voltage and conditions. Under Condition 2 for systems up to 150 volts
to ground, a minimum depth of 3 feet 6 inches is required.
, 6. EMT is commonly supported within what maximum distance of
each outlet box?
A. 10 feet
B. 3 feet
C. 5 feet
D. 6 feet
Rationale: NEC 358.30 requires EMT to be securely fastened within 3
feet of each outlet, junction, device, cabinet, conduit body, or
termination unless otherwise permitted.
7. What color insulation is typically used for equipment grounding
conductors?
A. Black
B. Red
C. White
D. Green
Rationale: Green or bare conductors are designated for equipment
grounding conductors. White or gray conductors are reserved for
grounded (neutral) conductors.