Tennessee Electrical Contractor Exam –
Street Lighting Systems Exam Practice
Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. In a typical street lighting system, which component is primarily
responsible for stepping down distribution voltage to a usable level for
luminaires?
A. Photocell controller
B. Ballast
C. Transformer
D. Fuse
C. Transformer
The transformer reduces high distribution voltage (e.g., 13.2 kV) to
lower utilization voltages suitable for street lighting systems,
ensuring safe and efficient operation.
2. Which type of lamp is most commonly used in modern energy-
efficient street lighting systems?
A. Incandescent lamp
B. High-pressure sodium lamp
C. LED lamp
D. Mercury vapor lamp
C. LED lamp
, LED lamps are widely used due to their high efficiency, long lifespan,
low maintenance requirements, and superior light quality compared
to older technologies.
3. What is the primary function of a photocell in street lighting?
A. Increase voltage
B. Detect ambient light levels
C. Regulate current flow
D. Store electrical energy
B. Detect ambient light levels
A photocell automatically turns street lights on at dusk and off at
dawn by sensing ambient light levels, improving efficiency and
automation.
4. Which wiring configuration is commonly used in street lighting
circuits?
A. Series circuit
B. Parallel circuit
C. Star-delta circuit
D. Bridge circuit
B. Parallel circuit
Parallel circuits allow each luminaire to operate independently so
that failure of one light does not affect others.
5. What is the primary purpose of a ballast in HID street lighting?
A. Reduce voltage spikes
B. Limit current to the lamp
C. Convert AC to DC
D. Store energy
B. Limit current to the lamp
Ballasts regulate current flow to high-intensity discharge lamps,
preventing excessive current that could damage the lamp.
6. Which factor most significantly affects the spacing of street lighting
poles?
A. Wire gauge
B. Pole color
, C. Lamp wattage and illumination requirements
D. Transformer size
C. Lamp wattage and illumination requirements
Pole spacing is determined by required illumination levels, lamp
output, mounting height, and roadway classification.
7. What is the typical mounting height for street lighting poles on major
roadways?
A. 5–10 feet
B. 10–15 feet
C. 20–40 feet
D. 50–70 feet
C. 20–40 feet
Major roadways require higher mounting heights to achieve broader
light distribution and reduce glare.
8. Which type of conductor insulation is commonly used for underground
street lighting circuits?
A. THHN
B. XHHW
C. UF
D. NM
B. XHHW
XHHW insulation is suitable for underground applications due to its
moisture resistance and durability.
9. What is the purpose of a handhole in a street lighting pole?
A. Increase airflow
B. Provide access for wiring connections
C. Support structural integrity
D. Reduce weight
B. Provide access for wiring connections
Handholes allow electricians to access internal wiring for
maintenance and connections.
10. Which protective device is typically used to protect street
lighting circuits from overcurrent?
Street Lighting Systems Exam Practice
Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. In a typical street lighting system, which component is primarily
responsible for stepping down distribution voltage to a usable level for
luminaires?
A. Photocell controller
B. Ballast
C. Transformer
D. Fuse
C. Transformer
The transformer reduces high distribution voltage (e.g., 13.2 kV) to
lower utilization voltages suitable for street lighting systems,
ensuring safe and efficient operation.
2. Which type of lamp is most commonly used in modern energy-
efficient street lighting systems?
A. Incandescent lamp
B. High-pressure sodium lamp
C. LED lamp
D. Mercury vapor lamp
C. LED lamp
, LED lamps are widely used due to their high efficiency, long lifespan,
low maintenance requirements, and superior light quality compared
to older technologies.
3. What is the primary function of a photocell in street lighting?
A. Increase voltage
B. Detect ambient light levels
C. Regulate current flow
D. Store electrical energy
B. Detect ambient light levels
A photocell automatically turns street lights on at dusk and off at
dawn by sensing ambient light levels, improving efficiency and
automation.
4. Which wiring configuration is commonly used in street lighting
circuits?
A. Series circuit
B. Parallel circuit
C. Star-delta circuit
D. Bridge circuit
B. Parallel circuit
Parallel circuits allow each luminaire to operate independently so
that failure of one light does not affect others.
5. What is the primary purpose of a ballast in HID street lighting?
A. Reduce voltage spikes
B. Limit current to the lamp
C. Convert AC to DC
D. Store energy
B. Limit current to the lamp
Ballasts regulate current flow to high-intensity discharge lamps,
preventing excessive current that could damage the lamp.
6. Which factor most significantly affects the spacing of street lighting
poles?
A. Wire gauge
B. Pole color
, C. Lamp wattage and illumination requirements
D. Transformer size
C. Lamp wattage and illumination requirements
Pole spacing is determined by required illumination levels, lamp
output, mounting height, and roadway classification.
7. What is the typical mounting height for street lighting poles on major
roadways?
A. 5–10 feet
B. 10–15 feet
C. 20–40 feet
D. 50–70 feet
C. 20–40 feet
Major roadways require higher mounting heights to achieve broader
light distribution and reduce glare.
8. Which type of conductor insulation is commonly used for underground
street lighting circuits?
A. THHN
B. XHHW
C. UF
D. NM
B. XHHW
XHHW insulation is suitable for underground applications due to its
moisture resistance and durability.
9. What is the purpose of a handhole in a street lighting pole?
A. Increase airflow
B. Provide access for wiring connections
C. Support structural integrity
D. Reduce weight
B. Provide access for wiring connections
Handholes allow electricians to access internal wiring for
maintenance and connections.
10. Which protective device is typically used to protect street
lighting circuits from overcurrent?
