Alabama Electrical Contractor Licensing
Exam Verified Questions, Correct Answers,
and Detailed Explanations for
Students||Already Graded A+
1. Which of the following is the primary purpose of the National Electrical
Code (NEC)?
A) To regulate energy pricing
B) To ensure electrical safety and prevent hazards
C) To standardize electrical equipment branding
D) To set building aesthetics
The NEC sets safety standards to prevent electrical fires, shocks, and other
hazards in installations.
2. The minimum wire size for a 20-amp residential circuit is:
A) 10 AWG
B) 12 AWG
C) 14 AWG
D) 16 AWG
According to the NEC, a 20-amp circuit typically requires 12 AWG copper, but
14 AWG is standard for 15-amp circuits. Careful reading of code requirements
is critical.
3. What is the standard residential service voltage in the United States?
A) 120/208 V
B) 208 V
C) 240 V
D) 120/240 V
Most U.S. homes use a split-phase 120/240 V system to power standard and
high-demand appliances.
,4. What type of conduit is typically used outdoors for electrical wiring?
A) FMC
B) RMC
C) NM-B
D) ENT
Rigid Metal Conduit (RMC) is used outdoors for protection against weather and
physical damage.
5. Which device protects a circuit from overcurrent?
A) GFCI
B) Circuit breaker
C) Switch
D) Contactor
Circuit breakers interrupt current flow when it exceeds safe limits, protecting
wiring and devices.
6. Ground-fault circuit interrupters (GFCIs) are required in which locations?
A) Bedrooms
B) Bathrooms, kitchens, and outdoors
C) Living rooms
D) Basements only
GFCIs protect people from electrical shock in areas with high moisture.
7. A 240-volt appliance requires a breaker rated at:
A) 15 A
B) 20 A
C) 30 A
D) Depends on appliance amperage
Breaker size must match the appliance's current rating to prevent overloading
and ensure safety.
, 8. The NEC requires that service panels be installed at a minimum height of:
A) 4 feet
B) 6 feet 7 inches maximum to handle
C) 7 feet 6 inches
D) 3 feet
NEC 240.24 and related codes regulate panel accessibility and height for safety
and convenience.
9. Which color of wire is typically used for grounding?
A) Red
B) Black
C) White
D) Green or bare copper
Green or bare copper wires are universally recognized for grounding to prevent
electrical shock.
10. Aluminum conductors must be:
A) Properly rated and connectors approved for aluminum
B) Connected with standard copper wire nuts
C) Coated with oil
D) None of the above
Aluminum has higher resistance and expansion properties, so connectors and
terminals must be rated for it.
11. What is the maximum distance a 15-amp circuit can run with 14 AWG
wire before voltage drop becomes a concern?
A) 50 feet
B) 100 feet
C) 150 feet
D) Approx. 100 feet for standard voltage drop considerations
Exam Verified Questions, Correct Answers,
and Detailed Explanations for
Students||Already Graded A+
1. Which of the following is the primary purpose of the National Electrical
Code (NEC)?
A) To regulate energy pricing
B) To ensure electrical safety and prevent hazards
C) To standardize electrical equipment branding
D) To set building aesthetics
The NEC sets safety standards to prevent electrical fires, shocks, and other
hazards in installations.
2. The minimum wire size for a 20-amp residential circuit is:
A) 10 AWG
B) 12 AWG
C) 14 AWG
D) 16 AWG
According to the NEC, a 20-amp circuit typically requires 12 AWG copper, but
14 AWG is standard for 15-amp circuits. Careful reading of code requirements
is critical.
3. What is the standard residential service voltage in the United States?
A) 120/208 V
B) 208 V
C) 240 V
D) 120/240 V
Most U.S. homes use a split-phase 120/240 V system to power standard and
high-demand appliances.
,4. What type of conduit is typically used outdoors for electrical wiring?
A) FMC
B) RMC
C) NM-B
D) ENT
Rigid Metal Conduit (RMC) is used outdoors for protection against weather and
physical damage.
5. Which device protects a circuit from overcurrent?
A) GFCI
B) Circuit breaker
C) Switch
D) Contactor
Circuit breakers interrupt current flow when it exceeds safe limits, protecting
wiring and devices.
6. Ground-fault circuit interrupters (GFCIs) are required in which locations?
A) Bedrooms
B) Bathrooms, kitchens, and outdoors
C) Living rooms
D) Basements only
GFCIs protect people from electrical shock in areas with high moisture.
7. A 240-volt appliance requires a breaker rated at:
A) 15 A
B) 20 A
C) 30 A
D) Depends on appliance amperage
Breaker size must match the appliance's current rating to prevent overloading
and ensure safety.
, 8. The NEC requires that service panels be installed at a minimum height of:
A) 4 feet
B) 6 feet 7 inches maximum to handle
C) 7 feet 6 inches
D) 3 feet
NEC 240.24 and related codes regulate panel accessibility and height for safety
and convenience.
9. Which color of wire is typically used for grounding?
A) Red
B) Black
C) White
D) Green or bare copper
Green or bare copper wires are universally recognized for grounding to prevent
electrical shock.
10. Aluminum conductors must be:
A) Properly rated and connectors approved for aluminum
B) Connected with standard copper wire nuts
C) Coated with oil
D) None of the above
Aluminum has higher resistance and expansion properties, so connectors and
terminals must be rated for it.
11. What is the maximum distance a 15-amp circuit can run with 14 AWG
wire before voltage drop becomes a concern?
A) 50 feet
B) 100 feet
C) 150 feet
D) Approx. 100 feet for standard voltage drop considerations
