New York City Master Electrician Exam
Practice Questions and Correct Answers
(Verified Answers) Plus Rationales 2027
Q&A | Instant Download Pdf
1. What is the primary purpose of an overcurrent protective device?
A. Increase circuit voltage
B. Improve power factor
C. Protect conductors and equipment from excessive current
D. Provide normal operating current to the grounding system
Answer: C. Protect conductors and equipment from excessive current
Rationale: Overcurrent protective devices limit excessive current to help prevent
conductor overheating, equipment damage, and fire hazards. They do not increase
voltage or serve as the normal current path for grounding conductors.
2. Which NEC article primarily addresses branch circuits?
A. Article 210
B. Article 215
C. Article 230
D. Article 250
Answer: A. Article 210
Rationale: Article 210 establishes requirements for branch circuits, including their
ratings, conductors, overcurrent protection, and certain receptacle and outlet
provisions.
3. A 120-volt load draws 10 amperes. What is its approximate power
consumption?
,A. 12 watts
B. 120 watts
C. 1,000 watts
D. 1,200 watts
Answer: B. 120 watts
Rationale: Using the basic power relationship P = E × I, the load consumes 120 V ×
10 A = 1,200 watts. Therefore, the correct answer is D.
4. Which conductor normally carries the return current in a typical 120-volt
single-phase circuit?
A. Equipment grounding conductor
B. Grounding electrode conductor
C. Bonding jumper
D. Grounded conductor
Answer: D. Grounded conductor
Rationale: In a typical grounded single-phase circuit, the grounded conductor,
commonly called the neutral, carries the return current from the load toward the
source. Equipment grounding and bonding conductors are not intended to carry
normal load current.
5. What is the principal purpose of bonding?
A. Increase conductor ampacity
B. Establish electrical continuity between conductive parts
C. Reduce normal load current
D. Increase system frequency
Answer: B. Establish electrical continuity between conductive parts
Rationale: Bonding connects conductive parts together to establish an effective
fault-current path and help keep exposed conductive surfaces at substantially the
same electrical potential during a fault.
,6. Which condition is most important when determining conductor ampacity?
A. The color of the conductor insulation
B. The manufacturer's logo
C. The conductor's size, insulation rating, and applicable installation conditions
D. The length of the circuit only
Answer: C. The conductor's size, insulation rating, and applicable installation
conditions
Rationale: Allowable ampacity depends on conductor characteristics and
installation conditions, including factors such as conductor size, insulation
temperature rating, ambient temperature, and the number of current-carrying
conductors.
7. What is the primary function of a feeder?
A. Supply branch-circuit overcurrent devices or distribution equipment
B. Connect a lighting fixture to a switch only
C. Provide only a grounding connection
D. Replace service equipment
Answer: A. Supply branch-circuit overcurrent devices or distribution equipment
Rationale: A feeder carries power from service equipment or another power
source to branch-circuit overcurrent devices or distribution equipment.
8. Which calculation determines the total connected load of multiple electrical
loads?
A. Conductor resistance calculation
B. Voltage-drop calculation only
C. Short-circuit impedance calculation
D. Load calculation
Answer: D. Load calculation
, Rationale: A load calculation determines the electrical demand associated with
connected loads and is used when sizing services, feeders, and other portions of an
electrical distribution system.
9. What is the primary purpose of a grounding electrode system?
A. Carry normal branch-circuit current
B. Connect the electrical system to the grounding electrode system as required
C. Increase circuit voltage
D. Replace branch-circuit overcurrent protection
Answer: B. Connect the electrical system to the grounding electrode system as
required
Rationale: Grounding electrode conductors connect the grounded electrical system
or equipment, as applicable, to the grounding electrode system. The grounding
electrode system serves the grounding functions required by the electrical code.
10. What is the primary purpose of a service disconnecting means?
A. Increase the available fault current
B. Provide a path for normal neutral current
C. Disconnect the premises wiring system from the service supply
D. Replace branch-circuit breakers
Answer: C. Disconnect the premises wiring system from the service supply
Rationale: The service disconnect provides a means of disconnecting the premises
wiring system from the service supply for safety, maintenance, and emergency
purposes.
11. Which condition generally requires correction during an electrical
inspection?
A. A properly identified circuit directory
B. A listed enclosure installed according to its instructions
Practice Questions and Correct Answers
(Verified Answers) Plus Rationales 2027
Q&A | Instant Download Pdf
1. What is the primary purpose of an overcurrent protective device?
A. Increase circuit voltage
B. Improve power factor
C. Protect conductors and equipment from excessive current
D. Provide normal operating current to the grounding system
Answer: C. Protect conductors and equipment from excessive current
Rationale: Overcurrent protective devices limit excessive current to help prevent
conductor overheating, equipment damage, and fire hazards. They do not increase
voltage or serve as the normal current path for grounding conductors.
2. Which NEC article primarily addresses branch circuits?
A. Article 210
B. Article 215
C. Article 230
D. Article 250
Answer: A. Article 210
Rationale: Article 210 establishes requirements for branch circuits, including their
ratings, conductors, overcurrent protection, and certain receptacle and outlet
provisions.
3. A 120-volt load draws 10 amperes. What is its approximate power
consumption?
,A. 12 watts
B. 120 watts
C. 1,000 watts
D. 1,200 watts
Answer: B. 120 watts
Rationale: Using the basic power relationship P = E × I, the load consumes 120 V ×
10 A = 1,200 watts. Therefore, the correct answer is D.
4. Which conductor normally carries the return current in a typical 120-volt
single-phase circuit?
A. Equipment grounding conductor
B. Grounding electrode conductor
C. Bonding jumper
D. Grounded conductor
Answer: D. Grounded conductor
Rationale: In a typical grounded single-phase circuit, the grounded conductor,
commonly called the neutral, carries the return current from the load toward the
source. Equipment grounding and bonding conductors are not intended to carry
normal load current.
5. What is the principal purpose of bonding?
A. Increase conductor ampacity
B. Establish electrical continuity between conductive parts
C. Reduce normal load current
D. Increase system frequency
Answer: B. Establish electrical continuity between conductive parts
Rationale: Bonding connects conductive parts together to establish an effective
fault-current path and help keep exposed conductive surfaces at substantially the
same electrical potential during a fault.
,6. Which condition is most important when determining conductor ampacity?
A. The color of the conductor insulation
B. The manufacturer's logo
C. The conductor's size, insulation rating, and applicable installation conditions
D. The length of the circuit only
Answer: C. The conductor's size, insulation rating, and applicable installation
conditions
Rationale: Allowable ampacity depends on conductor characteristics and
installation conditions, including factors such as conductor size, insulation
temperature rating, ambient temperature, and the number of current-carrying
conductors.
7. What is the primary function of a feeder?
A. Supply branch-circuit overcurrent devices or distribution equipment
B. Connect a lighting fixture to a switch only
C. Provide only a grounding connection
D. Replace service equipment
Answer: A. Supply branch-circuit overcurrent devices or distribution equipment
Rationale: A feeder carries power from service equipment or another power
source to branch-circuit overcurrent devices or distribution equipment.
8. Which calculation determines the total connected load of multiple electrical
loads?
A. Conductor resistance calculation
B. Voltage-drop calculation only
C. Short-circuit impedance calculation
D. Load calculation
Answer: D. Load calculation
, Rationale: A load calculation determines the electrical demand associated with
connected loads and is used when sizing services, feeders, and other portions of an
electrical distribution system.
9. What is the primary purpose of a grounding electrode system?
A. Carry normal branch-circuit current
B. Connect the electrical system to the grounding electrode system as required
C. Increase circuit voltage
D. Replace branch-circuit overcurrent protection
Answer: B. Connect the electrical system to the grounding electrode system as
required
Rationale: Grounding electrode conductors connect the grounded electrical system
or equipment, as applicable, to the grounding electrode system. The grounding
electrode system serves the grounding functions required by the electrical code.
10. What is the primary purpose of a service disconnecting means?
A. Increase the available fault current
B. Provide a path for normal neutral current
C. Disconnect the premises wiring system from the service supply
D. Replace branch-circuit breakers
Answer: C. Disconnect the premises wiring system from the service supply
Rationale: The service disconnect provides a means of disconnecting the premises
wiring system from the service supply for safety, maintenance, and emergency
purposes.
11. Which condition generally requires correction during an electrical
inspection?
A. A properly identified circuit directory
B. A listed enclosure installed according to its instructions
