NYC Electrician Exam Practice Test
Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. What is the primary purpose of a grounding conductor in an electrical
system?
A) To carry the normal load current
B) To prevent overloading of the system
C) To provide a path for fault current to the earth
D) To step down voltage levels
Rationale: The grounding conductor provides a safe path for electricity in
case of a fault, preventing electric shock and equipment damage.
2. According to the National Electrical Code (NEC), what is the maximum
allowable voltage drop for branch circuits to maintain efficiency?
, A) 2%
B) 3%
C) 5%
D) 10%
Rationale: NEC recommends a maximum voltage drop of 3% for branch
circuits to ensure efficient operation of electrical devices.
3. Which type of conduit is typically used for underground installations?
A) EMT (Electrical Metallic Tubing)
B) PVC (Polyvinyl Chloride) Conduit
C) FMC (Flexible Metal Conduit)
D) ENT (Electrical Nonmetallic Tubing)
Rationale: PVC conduit is durable, corrosion-resistant, and suitable for
direct burial underground.
4. What is the primary function of a circuit breaker?
A) To step down voltage
B) To interrupt current flow during an overload or short circuit
C) To convert AC to DC
D) To measure current flow
Rationale: Circuit breakers automatically stop electrical flow when unsafe
conditions occur, protecting wiring and devices.
, 5. In a three-phase system, what is the phase-to-phase voltage if the
phase-to-neutral voltage is 120 V?
A) 120 V
B) 208 V
C) 240 V
D) 208 V
Rationale: In a three-phase, 120 V phase-to-neutral system, the phase-to-
phase voltage is 120 × √3 ≈ 208 V.
6. Which wire color is commonly used for a neutral conductor in
residential wiring?
A) Red
B) Black
C) White
D) Green
Rationale: NEC requires white or gray insulation for neutral conductors to
clearly distinguish them from hot wires.
7. What is the main hazard associated with aluminum wiring?
A) High resistance
B) Low voltage drop
, C) Connection overheating due to oxidation
D) Excessive flexibility
Rationale: Aluminum wiring can oxidize at connections, causing
overheating and potential fire hazards.
8. Which tool is used to measure the current flowing through a
conductor without disconnecting it?
A) Multimeter
B) Voltage tester
C) Clamp meter
D) Ohmmeter
Rationale: Clamp meters measure current by detecting the magnetic field
around a conductor, without needing to break the circuit.
9. Which type of overcurrent protection device is designed to protect
against short circuits and overloads?
A) Fuse only
B) Circuit breaker only
C) Both fuse and circuit breaker
D) Transformer
Rationale: Both fuses and circuit breakers protect circuits by interrupting
excessive current flow from short circuits or overloads.
Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. What is the primary purpose of a grounding conductor in an electrical
system?
A) To carry the normal load current
B) To prevent overloading of the system
C) To provide a path for fault current to the earth
D) To step down voltage levels
Rationale: The grounding conductor provides a safe path for electricity in
case of a fault, preventing electric shock and equipment damage.
2. According to the National Electrical Code (NEC), what is the maximum
allowable voltage drop for branch circuits to maintain efficiency?
, A) 2%
B) 3%
C) 5%
D) 10%
Rationale: NEC recommends a maximum voltage drop of 3% for branch
circuits to ensure efficient operation of electrical devices.
3. Which type of conduit is typically used for underground installations?
A) EMT (Electrical Metallic Tubing)
B) PVC (Polyvinyl Chloride) Conduit
C) FMC (Flexible Metal Conduit)
D) ENT (Electrical Nonmetallic Tubing)
Rationale: PVC conduit is durable, corrosion-resistant, and suitable for
direct burial underground.
4. What is the primary function of a circuit breaker?
A) To step down voltage
B) To interrupt current flow during an overload or short circuit
C) To convert AC to DC
D) To measure current flow
Rationale: Circuit breakers automatically stop electrical flow when unsafe
conditions occur, protecting wiring and devices.
, 5. In a three-phase system, what is the phase-to-phase voltage if the
phase-to-neutral voltage is 120 V?
A) 120 V
B) 208 V
C) 240 V
D) 208 V
Rationale: In a three-phase, 120 V phase-to-neutral system, the phase-to-
phase voltage is 120 × √3 ≈ 208 V.
6. Which wire color is commonly used for a neutral conductor in
residential wiring?
A) Red
B) Black
C) White
D) Green
Rationale: NEC requires white or gray insulation for neutral conductors to
clearly distinguish them from hot wires.
7. What is the main hazard associated with aluminum wiring?
A) High resistance
B) Low voltage drop
, C) Connection overheating due to oxidation
D) Excessive flexibility
Rationale: Aluminum wiring can oxidize at connections, causing
overheating and potential fire hazards.
8. Which tool is used to measure the current flowing through a
conductor without disconnecting it?
A) Multimeter
B) Voltage tester
C) Clamp meter
D) Ohmmeter
Rationale: Clamp meters measure current by detecting the magnetic field
around a conductor, without needing to break the circuit.
9. Which type of overcurrent protection device is designed to protect
against short circuits and overloads?
A) Fuse only
B) Circuit breaker only
C) Both fuse and circuit breaker
D) Transformer
Rationale: Both fuses and circuit breakers protect circuits by interrupting
excessive current flow from short circuits or overloads.
