CALIFORNIA GENERAL ELECTRICIAN
CERTIFICATION EXAM ACTUAL 2026
VERIFIED QUESTIONS WITH ANSWERS
COMPREHENSIVE & RATIONALE
1. A 120/240-volt single-phase feeder supplies a dwelling subpanel.
The ungrounded conductors are protected at 100 amperes. What is
the minimum copper equipment grounding conductor size required
by NEC Table 250.122?
A. 14 AWG
B. 12 AWG
C. 10 AWG
D. 8 AWG
Answer: C. 10 AWG
Rationale: NEC Table 250.122 requires equipment grounding
conductor sizing based on the rating of the overcurrent protective
device. A 100-ampere circuit requires a minimum 8 AWG copper EGC
if using the table values. However, if the conductors are adjusted for
voltage drop or increased in size, proportional adjustment may apply.
For a standard 100-ampere feeder, the required copper EGC is 8
AWG. Therefore, the correct answer should be D. 8 AWG.
2. What is the primary purpose of bonding metal water piping to the
electrical grounding system?
A. To increase circuit voltage
B. To eliminate all corrosion
C. To provide an effective fault current path
D. To reduce conductor resistance
1
,Answer: C. To provide an effective fault current path
Rationale: Bonding creates a low-impedance path that allows fault
current to return to the source, causing protective devices to open the
circuit quickly during a ground fault.
3. A conductor carries continuous loads only. According to NEC
requirements, the conductor ampacity must be sized at what
percentage of the continuous load?
A. 80%
B. 100%
C. 125%
D. 150%
Answer: C. 125%
Rationale: Continuous loads are defined as loads operating for three
hours or more. NEC requires branch-circuit and feeder conductors to
have an ampacity not less than 125% of the continuous load.
4. A 20-ampere, 120-volt branch circuit supplies receptacles in a
commercial building. What is the minimum copper conductor size
permitted?
A. 14 AWG
B. 12 AWG
C. 10 AWG
D. 8 AWG
Answer: B. 12 AWG
Rationale: A 20-ampere branch circuit requires a minimum of 12
AWG copper conductors unless special conditions apply.
2
,5. What instrument is used to measure insulation resistance of
electrical conductors?
A. Clamp meter
B. Megohmmeter
C. Wattmeter
D. Frequency meter
Answer: B. Megohmmeter
Rationale: A megohmmeter applies a high DC voltage to test
insulation integrity and measures resistance in megohms.
6. What is the maximum number of current-carrying conductors
allowed before adjustment factors must be applied?
A. 3
B. 6
C. 9
D. 12
Answer: C. 9
Rationale: NEC ampacity adjustment requirements apply when more
than three current-carrying conductors are installed in the same
raceway, cable, or enclosure.
7. A motor has a nameplate full-load current of 40 amperes. What
minimum conductor ampacity is required?
A. 40 amperes
B. 45 amperes
3
, C. 50 amperes
D. 60 amperes
Answer: C. 50 amperes
Rationale: Motor branch-circuit conductors must generally be sized at
125% of motor full-load current. 40 × 1.25 = 50 amperes.
8. What device protects personnel from electric shock by detecting
small leakage currents?
A. Circuit breaker
B. AFCI
C. GFCI
D. Disconnect switch
Answer: C. GFCI
Rationale: A ground-fault circuit interrupter trips when it detects an
imbalance between outgoing and returning current, typically around
4–6 milliamperes.
9. What is the purpose of a transformer?
A. Increase resistance
B. Change AC voltage levels
C. Convert AC to DC
D. Reduce conductor size requirements
Answer: B. Change AC voltage levels
Rationale: Transformers use electromagnetic induction to increase or
decrease alternating current voltage while maintaining frequency.
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CERTIFICATION EXAM ACTUAL 2026
VERIFIED QUESTIONS WITH ANSWERS
COMPREHENSIVE & RATIONALE
1. A 120/240-volt single-phase feeder supplies a dwelling subpanel.
The ungrounded conductors are protected at 100 amperes. What is
the minimum copper equipment grounding conductor size required
by NEC Table 250.122?
A. 14 AWG
B. 12 AWG
C. 10 AWG
D. 8 AWG
Answer: C. 10 AWG
Rationale: NEC Table 250.122 requires equipment grounding
conductor sizing based on the rating of the overcurrent protective
device. A 100-ampere circuit requires a minimum 8 AWG copper EGC
if using the table values. However, if the conductors are adjusted for
voltage drop or increased in size, proportional adjustment may apply.
For a standard 100-ampere feeder, the required copper EGC is 8
AWG. Therefore, the correct answer should be D. 8 AWG.
2. What is the primary purpose of bonding metal water piping to the
electrical grounding system?
A. To increase circuit voltage
B. To eliminate all corrosion
C. To provide an effective fault current path
D. To reduce conductor resistance
1
,Answer: C. To provide an effective fault current path
Rationale: Bonding creates a low-impedance path that allows fault
current to return to the source, causing protective devices to open the
circuit quickly during a ground fault.
3. A conductor carries continuous loads only. According to NEC
requirements, the conductor ampacity must be sized at what
percentage of the continuous load?
A. 80%
B. 100%
C. 125%
D. 150%
Answer: C. 125%
Rationale: Continuous loads are defined as loads operating for three
hours or more. NEC requires branch-circuit and feeder conductors to
have an ampacity not less than 125% of the continuous load.
4. A 20-ampere, 120-volt branch circuit supplies receptacles in a
commercial building. What is the minimum copper conductor size
permitted?
A. 14 AWG
B. 12 AWG
C. 10 AWG
D. 8 AWG
Answer: B. 12 AWG
Rationale: A 20-ampere branch circuit requires a minimum of 12
AWG copper conductors unless special conditions apply.
2
,5. What instrument is used to measure insulation resistance of
electrical conductors?
A. Clamp meter
B. Megohmmeter
C. Wattmeter
D. Frequency meter
Answer: B. Megohmmeter
Rationale: A megohmmeter applies a high DC voltage to test
insulation integrity and measures resistance in megohms.
6. What is the maximum number of current-carrying conductors
allowed before adjustment factors must be applied?
A. 3
B. 6
C. 9
D. 12
Answer: C. 9
Rationale: NEC ampacity adjustment requirements apply when more
than three current-carrying conductors are installed in the same
raceway, cable, or enclosure.
7. A motor has a nameplate full-load current of 40 amperes. What
minimum conductor ampacity is required?
A. 40 amperes
B. 45 amperes
3
, C. 50 amperes
D. 60 amperes
Answer: C. 50 amperes
Rationale: Motor branch-circuit conductors must generally be sized at
125% of motor full-load current. 40 × 1.25 = 50 amperes.
8. What device protects personnel from electric shock by detecting
small leakage currents?
A. Circuit breaker
B. AFCI
C. GFCI
D. Disconnect switch
Answer: C. GFCI
Rationale: A ground-fault circuit interrupter trips when it detects an
imbalance between outgoing and returning current, typically around
4–6 milliamperes.
9. What is the purpose of a transformer?
A. Increase resistance
B. Change AC voltage levels
C. Convert AC to DC
D. Reduce conductor size requirements
Answer: B. Change AC voltage levels
Rationale: Transformers use electromagnetic induction to increase or
decrease alternating current voltage while maintaining frequency.
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