Journeyman Lineman Examination Questions
With Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download Pdf
1. What is the primary purpose of a step-down transformer in a
distribution system?
A. Increase voltage for transmission
B. Reduce current for efficiency
C. Reduce voltage for end-use distribution
D. Store electrical energy
Answer: C
Rationale: A step-down transformer decreases high transmission
voltages to safer, usable levels for residential and commercial
distribution, making it suitable for consumer equipment and reducing
insulation requirements.
2. Which material is most commonly used for overhead transmission
conductors?
A. Copper
, B. Aluminum
C. Steel
D. Silver
Answer: B
Rationale: Aluminum is widely used because it offers a good balance
of conductivity, weight, cost, and mechanical strength, especially
when reinforced with steel (ACSR).
3. What is the function of a circuit breaker?
A. Increase voltage
B. Automatically interrupt fault current
C. Store electrical energy
D. Convert AC to DC
Answer: B
Rationale: Circuit breakers protect systems by automatically opening
the circuit when overcurrent or faults occur, preventing equipment
damage and fire hazards.
4. What type of current is typically used in transmission systems?
A. Direct current
, B. Alternating current
C. Pulsating DC
D. Static current
Answer: B
Rationale: Alternating current (AC) is used because it is easier to
transform to different voltage levels, improving efficiency over long
distances.
5. What tool is used to measure electrical current in a live conductor
without disconnecting it?
A. Ohmmeter
B. Voltmeter
C. Clamp meter
D. Megohmmeter
Answer: C
Rationale: A clamp meter measures current by detecting the magnetic
field around a conductor, allowing safe, non-intrusive measurement.
6. What is the purpose of grounding in electrical systems?
A. Increase voltage stability
, B. Provide a path for fault current to earth
C. Store excess electricity
D. Reduce conductor resistance
Answer: B
Rationale: Grounding ensures fault currents are safely directed into
the earth, protecting equipment and reducing shock hazards.
7. Which device protects against lightning surges in power lines?
A. Fuse
B. Surge arrester
C. Transformer
D. Capacitor
Answer: B
Rationale: Surge arresters divert high-voltage lightning surges safely
to ground, protecting equipment from insulation failure.
8. What is the standard frequency of electrical power in most
regions?
A. 25 Hz
B. 50–60 Hz
With Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download Pdf
1. What is the primary purpose of a step-down transformer in a
distribution system?
A. Increase voltage for transmission
B. Reduce current for efficiency
C. Reduce voltage for end-use distribution
D. Store electrical energy
Answer: C
Rationale: A step-down transformer decreases high transmission
voltages to safer, usable levels for residential and commercial
distribution, making it suitable for consumer equipment and reducing
insulation requirements.
2. Which material is most commonly used for overhead transmission
conductors?
A. Copper
, B. Aluminum
C. Steel
D. Silver
Answer: B
Rationale: Aluminum is widely used because it offers a good balance
of conductivity, weight, cost, and mechanical strength, especially
when reinforced with steel (ACSR).
3. What is the function of a circuit breaker?
A. Increase voltage
B. Automatically interrupt fault current
C. Store electrical energy
D. Convert AC to DC
Answer: B
Rationale: Circuit breakers protect systems by automatically opening
the circuit when overcurrent or faults occur, preventing equipment
damage and fire hazards.
4. What type of current is typically used in transmission systems?
A. Direct current
, B. Alternating current
C. Pulsating DC
D. Static current
Answer: B
Rationale: Alternating current (AC) is used because it is easier to
transform to different voltage levels, improving efficiency over long
distances.
5. What tool is used to measure electrical current in a live conductor
without disconnecting it?
A. Ohmmeter
B. Voltmeter
C. Clamp meter
D. Megohmmeter
Answer: C
Rationale: A clamp meter measures current by detecting the magnetic
field around a conductor, allowing safe, non-intrusive measurement.
6. What is the purpose of grounding in electrical systems?
A. Increase voltage stability
, B. Provide a path for fault current to earth
C. Store excess electricity
D. Reduce conductor resistance
Answer: B
Rationale: Grounding ensures fault currents are safely directed into
the earth, protecting equipment and reducing shock hazards.
7. Which device protects against lightning surges in power lines?
A. Fuse
B. Surge arrester
C. Transformer
D. Capacitor
Answer: B
Rationale: Surge arresters divert high-voltage lightning surges safely
to ground, protecting equipment from insulation failure.
8. What is the standard frequency of electrical power in most
regions?
A. 25 Hz
B. 50–60 Hz
