CO Electrical Contractor Exam
Questions And Correct Answers
(Verified Answers) Plus Rationale2026
Q&A| Instant Download Pdf
conductors under a residential driveway?
A. 6 inches
B. 12 inches
C. 18 inches
D. 24 inches
Rationale: NEC Table 300.5 requires 18 inches for residential driveways.
2. What is the maximum allowable voltage drop for branch circuits to
ensure proper equipment performance?
A. 1%
B. 3%
C. 5%
D. 10%
Rationale: Total voltage drop for feeder + branch circuits should not
exceed 5%.
3. Which conductor color is permitted for an equipment grounding
conductor?
,A. Blue
B. Green
C. White
D. Red
Rationale: NEC requires equipment grounding conductors to be green,
green/yellow, or bare.
4. Which of the following locations requires GFCI protection?
A. Bedroom
B. Living room
C. Bathroom receptacle
D. Kitchen lighting
Rationale: Bathrooms require GFCI protection per NEC 210.8.
5. What is the minimum working clearance in front of a 480-V electrical
panel?
A. 12 inches
B. 24 inches
C. 36 inches
D. 48 inches
Rationale: NEC 110.26 requires 3 ft (36 in) clearance for 480-V systems.
6. What material is required for a grounding electrode conductor
exposed to potential physical damage?
A. Aluminum
B. Copper
C. Steel
D. Plastic
Rationale: Aluminum grounding conductors cannot be used where subject
to physical damage.
, 7. What is the maximum number of 90° bends allowed in a conduit run
between pull points?
A. 2
B. 3
C. 4
D. 5
Rationale: NEC permits up to four 90° bends per conduit run.
8. Which wire size is typically used for a 20-amp, 120-V branch circuit?
A. 16 AWG
B. 14 AWG
C. 12 AWG
D. 10 AWG
Rationale: 12 AWG copper is required for 20-amp circuits.
9. Which type of fire extinguisher is approved for electrical fires?
A. Class A
B. Class B
C. Class C
D. Class K
Rationale: Class C extinguishers are designed for energized electrical
equipment.
10. What is the required rating for receptacles in a commercial kitchen?
A. 10 A
B. 15 A
C. 20 A
Questions And Correct Answers
(Verified Answers) Plus Rationale2026
Q&A| Instant Download Pdf
conductors under a residential driveway?
A. 6 inches
B. 12 inches
C. 18 inches
D. 24 inches
Rationale: NEC Table 300.5 requires 18 inches for residential driveways.
2. What is the maximum allowable voltage drop for branch circuits to
ensure proper equipment performance?
A. 1%
B. 3%
C. 5%
D. 10%
Rationale: Total voltage drop for feeder + branch circuits should not
exceed 5%.
3. Which conductor color is permitted for an equipment grounding
conductor?
,A. Blue
B. Green
C. White
D. Red
Rationale: NEC requires equipment grounding conductors to be green,
green/yellow, or bare.
4. Which of the following locations requires GFCI protection?
A. Bedroom
B. Living room
C. Bathroom receptacle
D. Kitchen lighting
Rationale: Bathrooms require GFCI protection per NEC 210.8.
5. What is the minimum working clearance in front of a 480-V electrical
panel?
A. 12 inches
B. 24 inches
C. 36 inches
D. 48 inches
Rationale: NEC 110.26 requires 3 ft (36 in) clearance for 480-V systems.
6. What material is required for a grounding electrode conductor
exposed to potential physical damage?
A. Aluminum
B. Copper
C. Steel
D. Plastic
Rationale: Aluminum grounding conductors cannot be used where subject
to physical damage.
, 7. What is the maximum number of 90° bends allowed in a conduit run
between pull points?
A. 2
B. 3
C. 4
D. 5
Rationale: NEC permits up to four 90° bends per conduit run.
8. Which wire size is typically used for a 20-amp, 120-V branch circuit?
A. 16 AWG
B. 14 AWG
C. 12 AWG
D. 10 AWG
Rationale: 12 AWG copper is required for 20-amp circuits.
9. Which type of fire extinguisher is approved for electrical fires?
A. Class A
B. Class B
C. Class C
D. Class K
Rationale: Class C extinguishers are designed for energized electrical
equipment.
10. What is the required rating for receptacles in a commercial kitchen?
A. 10 A
B. 15 A
C. 20 A
