NYC ELECTRICIAN EXAM (CIVIL
SERVICE) PRACTICE QUESTIIONS
AND CORRECT ANSWERS WITH
VERIFIED SOLUTIONS 2026.
1. According to the National Electrical Code (NEC), what is the primary purpose of
bonding metal raceways and enclosures?
A. To increase voltage stability
B. To provide a low-impedance fault current path
C. To reduce conductor resistance
D. To improve load balancing
Correct Answer: B
Explanation: Bonding ensures that metal parts remain at the same electrical potential and
provides a low-impedance path for fault current, allowing overcurrent devices to operate
quickly. The other options are not the primary purpose of bonding.
2. What is the minimum cover requirement for rigid metal conduit (RMC) installed
under a residential driveway according to the NEC?
A. 6 inches
B. 12 inches
C. 18 inches
D. 24 inches
Correct Answer: C
Explanation: NEC Table 300.5 generally requires 18 inches of cover for rigid metal conduit
under residential driveways. Shallower depths may apply only under specific conditions.
3. A 20-amp branch circuit supplying continuous loads must have a maximum
continuous load of:
A. 16 amps
B. 18 amps
C. 20 amps
D. 25 amps
Correct Answer: A
Explanation: Continuous loads may not exceed 80% of the branch circuit rating. 80% of 20
amps equals 16 amps.
, 4. Which type of motor controller provides the highest starting torque?
A. Autotransformer starter
B. Wye-delta starter
C. Full-voltage starter
D. Soft starter
Correct Answer: C
Explanation: Full-voltage starters apply full line voltage directly to the motor, producing
maximum starting torque. Other methods reduce voltage and torque during startup.
5. What is the primary danger of an open neutral in a multiwire branch circuit?
A. Reduced conductor ampacity
B. Excessive voltage imbalance
C. Increased grounding resistance
D. Tripping of all breakers instantly
Correct Answer: B
Explanation: An open neutral can cause uneven voltage distribution across loads, potentially
damaging equipment due to overvoltage or undervoltage conditions.
6. In a delta-connected three-phase system, what is the relationship between line voltage
and phase voltage?
A. Line voltage equals phase voltage
B. Line voltage is twice phase voltage
C. Phase voltage is √3 times line voltage
D. Line voltage is √3 times phase voltage
Correct Answer: A
Explanation: In a delta system, line voltage equals phase voltage. The √3 relationship applies
to current in delta systems and voltage in wye systems.
7. What NEC article primarily covers grounding and bonding requirements?
A. Article 110
B. Article 250
C. Article 300
D. Article 430
Correct Answer: B
Explanation: NEC Article 250 contains the rules for grounding and bonding of electrical
systems and equipment.
, 8. A transformer has a primary voltage of 480V and a secondary voltage of 120V. What
is the turns ratio?
A. 1:2
B. 2:1
C. 4:1
D. 1:4
Correct Answer: C
Explanation: Transformer turns ratio equals primary voltage divided by secondary voltage.
480 ÷ 120 = 4, so the ratio is 4:1.
9. Which testing instrument is best suited for measuring insulation resistance?
A. Ammeter
B. Wattmeter
C. Megohmmeter
D. Oscilloscope
Correct Answer: C
Explanation: A megohmmeter, or “megger,” measures high resistance values in insulation
systems to detect deterioration or leakage.
10. What is the purpose of a ground-fault circuit interrupter (GFCI)?
A. To protect equipment from overload
B. To detect arcing conditions
C. To protect persons from electric shock
D. To stabilize voltage fluctuations
Correct Answer: C
Explanation: GFCIs detect small current imbalances between conductors and disconnect
power quickly to reduce shock hazards.
11. Which conductor type is most commonly used for branch circuit wiring in
commercial buildings?
A. THHN
B. UF
C. SE
D. USE
Correct Answer: A
Explanation: THHN conductors are commonly used in commercial branch circuits because
of their heat resistance and versatility in conduit systems.
SERVICE) PRACTICE QUESTIIONS
AND CORRECT ANSWERS WITH
VERIFIED SOLUTIONS 2026.
1. According to the National Electrical Code (NEC), what is the primary purpose of
bonding metal raceways and enclosures?
A. To increase voltage stability
B. To provide a low-impedance fault current path
C. To reduce conductor resistance
D. To improve load balancing
Correct Answer: B
Explanation: Bonding ensures that metal parts remain at the same electrical potential and
provides a low-impedance path for fault current, allowing overcurrent devices to operate
quickly. The other options are not the primary purpose of bonding.
2. What is the minimum cover requirement for rigid metal conduit (RMC) installed
under a residential driveway according to the NEC?
A. 6 inches
B. 12 inches
C. 18 inches
D. 24 inches
Correct Answer: C
Explanation: NEC Table 300.5 generally requires 18 inches of cover for rigid metal conduit
under residential driveways. Shallower depths may apply only under specific conditions.
3. A 20-amp branch circuit supplying continuous loads must have a maximum
continuous load of:
A. 16 amps
B. 18 amps
C. 20 amps
D. 25 amps
Correct Answer: A
Explanation: Continuous loads may not exceed 80% of the branch circuit rating. 80% of 20
amps equals 16 amps.
, 4. Which type of motor controller provides the highest starting torque?
A. Autotransformer starter
B. Wye-delta starter
C. Full-voltage starter
D. Soft starter
Correct Answer: C
Explanation: Full-voltage starters apply full line voltage directly to the motor, producing
maximum starting torque. Other methods reduce voltage and torque during startup.
5. What is the primary danger of an open neutral in a multiwire branch circuit?
A. Reduced conductor ampacity
B. Excessive voltage imbalance
C. Increased grounding resistance
D. Tripping of all breakers instantly
Correct Answer: B
Explanation: An open neutral can cause uneven voltage distribution across loads, potentially
damaging equipment due to overvoltage or undervoltage conditions.
6. In a delta-connected three-phase system, what is the relationship between line voltage
and phase voltage?
A. Line voltage equals phase voltage
B. Line voltage is twice phase voltage
C. Phase voltage is √3 times line voltage
D. Line voltage is √3 times phase voltage
Correct Answer: A
Explanation: In a delta system, line voltage equals phase voltage. The √3 relationship applies
to current in delta systems and voltage in wye systems.
7. What NEC article primarily covers grounding and bonding requirements?
A. Article 110
B. Article 250
C. Article 300
D. Article 430
Correct Answer: B
Explanation: NEC Article 250 contains the rules for grounding and bonding of electrical
systems and equipment.
, 8. A transformer has a primary voltage of 480V and a secondary voltage of 120V. What
is the turns ratio?
A. 1:2
B. 2:1
C. 4:1
D. 1:4
Correct Answer: C
Explanation: Transformer turns ratio equals primary voltage divided by secondary voltage.
480 ÷ 120 = 4, so the ratio is 4:1.
9. Which testing instrument is best suited for measuring insulation resistance?
A. Ammeter
B. Wattmeter
C. Megohmmeter
D. Oscilloscope
Correct Answer: C
Explanation: A megohmmeter, or “megger,” measures high resistance values in insulation
systems to detect deterioration or leakage.
10. What is the purpose of a ground-fault circuit interrupter (GFCI)?
A. To protect equipment from overload
B. To detect arcing conditions
C. To protect persons from electric shock
D. To stabilize voltage fluctuations
Correct Answer: C
Explanation: GFCIs detect small current imbalances between conductors and disconnect
power quickly to reduce shock hazards.
11. Which conductor type is most commonly used for branch circuit wiring in
commercial buildings?
A. THHN
B. UF
C. SE
D. USE
Correct Answer: A
Explanation: THHN conductors are commonly used in commercial branch circuits because
of their heat resistance and versatility in conduit systems.
