CALIFORNIA JOURNEYMAN ELECTRICIAN EXAM | ALL
QUESTIONS AND ANSWERS | A+ GRADED |
COMPREHENSIVE EXAM GUIDE 2026/2027
1. A general electrician is installing a branch circuit in a dwelling. Which conductor is
normally identified as the grounded (neutral) conductor?
A. Equipment grounding conductor
B. Ungrounded conductor
C. Grounded conductor
D. Bonding jumper
Answer: C
EXPLANATION: The grounded conductor is commonly called the neutral conductor and is
intentionally connected to the grounded system point. It normally carries return current from
line-to-neutral loads.
2. A 120-volt branch circuit supplies a 1,800-watt resistive heater. Approximately how
much current does the heater draw?
A. 7.5 A
B. 10 A
C. 12 A
D. 15 A
Answer: D
EXPLANATION: Using I = P ÷ E, the current is 1,800 ÷ 120 = 15 amperes.
3. During an installation, an electrician finds that the equipment grounding conductor is
undersized for the circuit and fault-current requirements. What is the best action?
A. Replace or correct the conductor before energizing the circuit
B. Increase the circuit voltage
C. Install a larger neutral conductor instead
D. Leave the installation unchanged if the circuit operates normally
Answer: A
EXPLANATION: The equipment grounding conductor must provide an effective fault-current
path. A circuit that operates normally can still be unsafe during a fault.
4. What is the primary purpose of an overcurrent protective device?
A. Increase available fault current
B. Protect conductors and equipment from excessive current
,C. Maintain constant voltage
D. Reduce normal operating resistance
Answer: B
EXPLANATION: Circuit breakers and fuses limit excessive current to help prevent conductor
overheating, equipment damage, and fire hazards.
5. An electrician is preparing to work inside a panelboard. What should be done before
beginning work?
A. Remove the panel cover immediately
B. Verify only the circuit voltage
C. De-energize the equipment and verify absence of voltage using appropriate procedures
D. Turn off the building's lighting only
Answer: C
EXPLANATION: Safe electrical work requires appropriate de-energization, lockout/tagout when
applicable, and verification that the conductors are actually de-energized.
6. A 20-ampere branch circuit is being installed to supply general-purpose receptacles.
Which conductor ampacity is generally required to be adequate for the circuit?
A. 14 amperes
B. 16 amperes
C. 18 amperes
D. 20 amperes
Answer: D
EXPLANATION: The branch-circuit conductors must have sufficient ampacity for the circuit
overcurrent protection and applicable code requirements.
7. What is the principal function of a bonding jumper?
A. Establish electrical continuity between metallic parts that must remain at substantially the
same potential
B. Increase the resistance of a circuit
C. Replace an overcurrent device
D. Provide additional operating voltage
Answer: A
EXPLANATION: Bonding provides a low-impedance path for fault current and helps ensure
exposed conductive parts remain at substantially the same electrical potential.
8. A receptacle is installed in a location where ground-fault protection is required. Which
device is specifically designed to provide this type of protection?
,A. AFCI
B. GFCI
C. Transformer
D. Disconnect switch
Answer: B
EXPLANATION: A ground-fault circuit interrupter detects an imbalance between current leaving
and returning through the circuit and can interrupt power rapidly.
9. An electrician measures 240 volts across two ungrounded conductors of a typical
residential multiwire system. What voltage would normally be measured from either
ungrounded conductor to the grounded conductor in a 120/240-volt system?
A. 24 V
B. 60 V
C. 120 V
D. 240 V
Answer: C
EXPLANATION: In a standard 120/240-volt single-phase system, each ungrounded conductor is
approximately 120 volts to the neutral, while the two ungrounded conductors are
approximately 240 volts apart.
10. Which instrument is most appropriate for measuring voltage between two points in an
energized circuit?
A. Voltmeter
B. Ammeter connected directly across the source
C. Megohmmeter only
D. Continuity tester only
Answer: A
EXPLANATION: A voltmeter is connected across the points whose potential difference is being
measured. An ammeter must not be connected directly across a voltage source.
11. A motor has a full-load current of 18 amperes. Before selecting conductors and
overcurrent protection, what information is most important to verify?
A. Paint color of the motor housing
B. Nameplate data and applicable code requirements
C. Length of the extension cord in the office
D. Number of light switches nearby
Answer: B
, EXPLANATION: Motor installations require evaluation of nameplate information, motor
characteristics, conductor ampacity, overcurrent protection, disconnecting means, and
applicable requirements.
12. What is the main purpose of a service disconnecting means?
A. Increase service voltage
B. Provide a means to disconnect the premises from the supply
C. Replace all branch-circuit breakers
D. Reduce conductor resistance
Answer: B
EXPLANATION: The service disconnect provides a means of disconnecting the premises wiring
from the supply under applicable requirements.
13. An electrician discovers a damaged conductor insulation inside a junction box. What is
the most appropriate response?
A. Cover the damage with ordinary tape regardless of severity
B. Leave it in place if no fault is currently present
C. Correct the damaged insulation using an approved repair or replace the conductor
D. Increase the breaker rating
Answer: C
EXPLANATION: Damaged insulation can compromise conductor safety. The appropriate repair
must restore the required insulation and integrity of the wiring method.
14. Which electrical quantity is measured in ohms?
A. Current
B. Resistance
C. Power
D. Frequency
Answer: B
EXPLANATION: Resistance is measured in ohms. Current is measured in amperes, power in
watts, and frequency in hertz.
15. A 120-volt load draws 8 amperes. Approximately how much power does it consume?
A. 960 W
B. 120 W
C. 15 W
D. 1,440 W
Answer: A
QUESTIONS AND ANSWERS | A+ GRADED |
COMPREHENSIVE EXAM GUIDE 2026/2027
1. A general electrician is installing a branch circuit in a dwelling. Which conductor is
normally identified as the grounded (neutral) conductor?
A. Equipment grounding conductor
B. Ungrounded conductor
C. Grounded conductor
D. Bonding jumper
Answer: C
EXPLANATION: The grounded conductor is commonly called the neutral conductor and is
intentionally connected to the grounded system point. It normally carries return current from
line-to-neutral loads.
2. A 120-volt branch circuit supplies a 1,800-watt resistive heater. Approximately how
much current does the heater draw?
A. 7.5 A
B. 10 A
C. 12 A
D. 15 A
Answer: D
EXPLANATION: Using I = P ÷ E, the current is 1,800 ÷ 120 = 15 amperes.
3. During an installation, an electrician finds that the equipment grounding conductor is
undersized for the circuit and fault-current requirements. What is the best action?
A. Replace or correct the conductor before energizing the circuit
B. Increase the circuit voltage
C. Install a larger neutral conductor instead
D. Leave the installation unchanged if the circuit operates normally
Answer: A
EXPLANATION: The equipment grounding conductor must provide an effective fault-current
path. A circuit that operates normally can still be unsafe during a fault.
4. What is the primary purpose of an overcurrent protective device?
A. Increase available fault current
B. Protect conductors and equipment from excessive current
,C. Maintain constant voltage
D. Reduce normal operating resistance
Answer: B
EXPLANATION: Circuit breakers and fuses limit excessive current to help prevent conductor
overheating, equipment damage, and fire hazards.
5. An electrician is preparing to work inside a panelboard. What should be done before
beginning work?
A. Remove the panel cover immediately
B. Verify only the circuit voltage
C. De-energize the equipment and verify absence of voltage using appropriate procedures
D. Turn off the building's lighting only
Answer: C
EXPLANATION: Safe electrical work requires appropriate de-energization, lockout/tagout when
applicable, and verification that the conductors are actually de-energized.
6. A 20-ampere branch circuit is being installed to supply general-purpose receptacles.
Which conductor ampacity is generally required to be adequate for the circuit?
A. 14 amperes
B. 16 amperes
C. 18 amperes
D. 20 amperes
Answer: D
EXPLANATION: The branch-circuit conductors must have sufficient ampacity for the circuit
overcurrent protection and applicable code requirements.
7. What is the principal function of a bonding jumper?
A. Establish electrical continuity between metallic parts that must remain at substantially the
same potential
B. Increase the resistance of a circuit
C. Replace an overcurrent device
D. Provide additional operating voltage
Answer: A
EXPLANATION: Bonding provides a low-impedance path for fault current and helps ensure
exposed conductive parts remain at substantially the same electrical potential.
8. A receptacle is installed in a location where ground-fault protection is required. Which
device is specifically designed to provide this type of protection?
,A. AFCI
B. GFCI
C. Transformer
D. Disconnect switch
Answer: B
EXPLANATION: A ground-fault circuit interrupter detects an imbalance between current leaving
and returning through the circuit and can interrupt power rapidly.
9. An electrician measures 240 volts across two ungrounded conductors of a typical
residential multiwire system. What voltage would normally be measured from either
ungrounded conductor to the grounded conductor in a 120/240-volt system?
A. 24 V
B. 60 V
C. 120 V
D. 240 V
Answer: C
EXPLANATION: In a standard 120/240-volt single-phase system, each ungrounded conductor is
approximately 120 volts to the neutral, while the two ungrounded conductors are
approximately 240 volts apart.
10. Which instrument is most appropriate for measuring voltage between two points in an
energized circuit?
A. Voltmeter
B. Ammeter connected directly across the source
C. Megohmmeter only
D. Continuity tester only
Answer: A
EXPLANATION: A voltmeter is connected across the points whose potential difference is being
measured. An ammeter must not be connected directly across a voltage source.
11. A motor has a full-load current of 18 amperes. Before selecting conductors and
overcurrent protection, what information is most important to verify?
A. Paint color of the motor housing
B. Nameplate data and applicable code requirements
C. Length of the extension cord in the office
D. Number of light switches nearby
Answer: B
, EXPLANATION: Motor installations require evaluation of nameplate information, motor
characteristics, conductor ampacity, overcurrent protection, disconnecting means, and
applicable requirements.
12. What is the main purpose of a service disconnecting means?
A. Increase service voltage
B. Provide a means to disconnect the premises from the supply
C. Replace all branch-circuit breakers
D. Reduce conductor resistance
Answer: B
EXPLANATION: The service disconnect provides a means of disconnecting the premises wiring
from the supply under applicable requirements.
13. An electrician discovers a damaged conductor insulation inside a junction box. What is
the most appropriate response?
A. Cover the damage with ordinary tape regardless of severity
B. Leave it in place if no fault is currently present
C. Correct the damaged insulation using an approved repair or replace the conductor
D. Increase the breaker rating
Answer: C
EXPLANATION: Damaged insulation can compromise conductor safety. The appropriate repair
must restore the required insulation and integrity of the wiring method.
14. Which electrical quantity is measured in ohms?
A. Current
B. Resistance
C. Power
D. Frequency
Answer: B
EXPLANATION: Resistance is measured in ohms. Current is measured in amperes, power in
watts, and frequency in hertz.
15. A 120-volt load draws 8 amperes. Approximately how much power does it consume?
A. 960 W
B. 120 W
C. 15 W
D. 1,440 W
Answer: A
