Texas Master Electrician License Exam Prep 2026
– Practice Questions, Answers & Detailed
Rationales
1. What is the minimum grounding electrode conductor size for a
200A service using copper?
A. 6 AWG
B. 4 AWG
C. 8 AWG
D. 2 AWG
The NEC requires a minimum 4 AWG copper grounding electrode
conductor for most 200A residential services when sized per Table
250.66 based on service conductor size.
2. What is the maximum number of disconnects allowed for a
service?
A. 2
B. 4
C. 6
D. 8
NEC allows up to six disconnects grouped as the service disconnecting
means.
3. Which conductor type is most suitable for wet locations?
A. THHN
B. THWN-2
,C. TFFN
D. TW
THWN-2 is rated for wet and dry locations and higher temperature
applications.
4. What is the voltage drop recommendation for branch circuits?
A. 1%
B. 3%
C. 3% maximum recommended
D. 10% allowed
NEC recommends no more than 3% voltage drop on branch circuits
for efficiency.
5. Which device protects against arc-faults?
A. GFCI
B. AFCI
C. Fuse
D. Relay
AFCI devices detect arc faults and reduce fire hazards.
6. What is the purpose of a GFCI?
A. Overload protection
B. Surge protection
C. Shock protection from ground faults
D. Lightning protection
GFCIs detect leakage current and protect against electric shock.
, 7. Minimum burial depth for residential branch circuits in PVC
conduit?
A. 6 inches
B. 12 inches
C. 18 inches
D. 24 inches
NEC Table 300.5 requires 18 inches for PVC residential branch circuits.
8. What does NEC Article 210 cover?
A. Motors
B. Grounding
C. Branch circuits
D. Transformers
Article 210 governs branch circuit requirements.
9. What is the standard frequency of U.S. power systems?
A. 50 Hz
B. 60 Hz
C. 100 Hz
D. 120 Hz
The United States standard frequency is 60 Hz.
10. What is the primary function of a transformer?
A. Store energy
B. Change voltage levels
C. Convert AC to DC
D. Limit current only
– Practice Questions, Answers & Detailed
Rationales
1. What is the minimum grounding electrode conductor size for a
200A service using copper?
A. 6 AWG
B. 4 AWG
C. 8 AWG
D. 2 AWG
The NEC requires a minimum 4 AWG copper grounding electrode
conductor for most 200A residential services when sized per Table
250.66 based on service conductor size.
2. What is the maximum number of disconnects allowed for a
service?
A. 2
B. 4
C. 6
D. 8
NEC allows up to six disconnects grouped as the service disconnecting
means.
3. Which conductor type is most suitable for wet locations?
A. THHN
B. THWN-2
,C. TFFN
D. TW
THWN-2 is rated for wet and dry locations and higher temperature
applications.
4. What is the voltage drop recommendation for branch circuits?
A. 1%
B. 3%
C. 3% maximum recommended
D. 10% allowed
NEC recommends no more than 3% voltage drop on branch circuits
for efficiency.
5. Which device protects against arc-faults?
A. GFCI
B. AFCI
C. Fuse
D. Relay
AFCI devices detect arc faults and reduce fire hazards.
6. What is the purpose of a GFCI?
A. Overload protection
B. Surge protection
C. Shock protection from ground faults
D. Lightning protection
GFCIs detect leakage current and protect against electric shock.
, 7. Minimum burial depth for residential branch circuits in PVC
conduit?
A. 6 inches
B. 12 inches
C. 18 inches
D. 24 inches
NEC Table 300.5 requires 18 inches for PVC residential branch circuits.
8. What does NEC Article 210 cover?
A. Motors
B. Grounding
C. Branch circuits
D. Transformers
Article 210 governs branch circuit requirements.
9. What is the standard frequency of U.S. power systems?
A. 50 Hz
B. 60 Hz
C. 100 Hz
D. 120 Hz
The United States standard frequency is 60 Hz.
10. What is the primary function of a transformer?
A. Store energy
B. Change voltage levels
C. Convert AC to DC
D. Limit current only
