Low Voltage Electrical Contractor
Examination Questions And Correct
Answers (Verified Answers) Plus
Rationales 2026 Q&A Instant Download
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Question 1
What is the minimum bending radius for a Category 6 unshielded twisted-pair
(UTP) cable during installation, expressed as a multiple of the cable’s outer
diameter?
A. 2 times
B. 4 times
C. 8 times
D. 10 times
Answer: B. 4 times
Rationale: TIA/EIA-568-B.2 specifies that the minimum bending radius for
Category 6 UTP cable is 4 times the cable diameter during installation and 2 times
for permanent installed conditions. This prevents signal degradation due to
excessive kinking or pair separation.**
Question 2
A fire alarm control panel (FACP) requires a dedicated branch circuit. What is the
maximum distance allowed between the panel and its overcurrent protection
device per NEC Article 760?
A. 3 feet
B. 5 feet
,C. 10 feet
D. 15 feet
Answer: C. 10 feet
Rationale: NEC 760.41(B) requires that the disconnecting means for a fire alarm
control panel be located within 10 feet of the panel and be readily accessible. This
ensures rapid power isolation during emergencies.**
Question 3
Which of the following is the maximum allowable resistance for a ground rod
electrode installed in a low-voltage system?
A. 5 ohms
B. 10 ohms
C. 25 ohms
D. 50 ohms
Answer: C. 25 ohms
Rationale: NEC 250.53(A)(2) requires that a single ground rod electrode have a
resistance to ground of 25 ohms or less. If resistance exceeds this, a second rod
must be installed or additional measures taken.**
Question 4
When terminating a shielded twisted-pair (STP) cable, where should the drain
wire be connected?
A. To the equipment ground at both ends
B. To the equipment ground at the patch panel only
C. To the equipment ground at the device end only
D. To a floating ground terminal
Answer: B. To the equipment ground at the patch panel only
Rationale: For STP cables, the drain wire should be grounded at the patch panel
(building ground) and left ungrounded at the device end to prevent ground loops,
which can introduce hum or noise in sensitive audio/video applications.**
,Question 5
What is the minimum insulation resistance test voltage for a 120V low-voltage
control circuit according to NETA standards?
A. 250V DC
B. 500V DC
C. 1000V DC
D. 1500V DC
Answer: B. 500V DC
Rationale: NETA ATS Table 100.1 specifies that insulation resistance testing for
circuits rated 250V or less should be performed at 500V DC. This provides a valid
indication of insulation integrity without overstressing low-voltage components.**
Question 6
In a Class 2 power-limited fire alarm system, what is the maximum output power
permitted per NEC?
A. 50 VA
B. 75 VA
C. 100 VA
D. 150 VA
Answer: C. 100 VA
Rationale: NEC 725.121(A) limits Class 2 power supplies to 100 VA maximum
output. This ensures the circuit is inherently limited and reduces fire and shock
hazards.**
Question 7
Which color pair is assigned to the first pair in a T568B wiring scheme for an 8P8C
(RJ45) connector?
A. Blue/White
B. Orange/White
, C. Green/White
D. Brown/White
Answer: B. Orange/White
Rationale: T568B uses the orange/white pair (pins 1-2) as Pair 1, green/white
(pins 3-6) as Pair 2, blue/white (pins 4-5) as Pair 3, and brown/white (pins 7-8) as
Pair 4.**
Question 8
A low-voltage technician is installing a CCTV system with 24V AC cameras. What is
the maximum recommended voltage drop for the power feeder?
A. 2%
B. 3%
C. 5%
D. 10%
Answer: C. 5%
Rationale: For low-voltage AC power distribution, a 5% voltage drop is typically
the maximum allowed to ensure proper camera operation. Many manufacturers
specify a tolerance of ±10%, but 5% is a conservative best practice.**
Question 9
What type of fire-rated cable is required for a circuit that must maintain operation
for 2 hours during a fire?
A. FPLP
B. FPLR
C. CI-Cable
D. CMP
Answer: C. CI-Cable
Rationale: Circuit Integrity (CI) cable, per NEC 760.176(F), is rated for 2-hour fire
survival. FPLP is plenum-rated but not fire-survival, FPLR is riser-rated, and CMP is
communications plenum cable.**
Examination Questions And Correct
Answers (Verified Answers) Plus
Rationales 2026 Q&A Instant Download
Question 1
What is the minimum bending radius for a Category 6 unshielded twisted-pair
(UTP) cable during installation, expressed as a multiple of the cable’s outer
diameter?
A. 2 times
B. 4 times
C. 8 times
D. 10 times
Answer: B. 4 times
Rationale: TIA/EIA-568-B.2 specifies that the minimum bending radius for
Category 6 UTP cable is 4 times the cable diameter during installation and 2 times
for permanent installed conditions. This prevents signal degradation due to
excessive kinking or pair separation.**
Question 2
A fire alarm control panel (FACP) requires a dedicated branch circuit. What is the
maximum distance allowed between the panel and its overcurrent protection
device per NEC Article 760?
A. 3 feet
B. 5 feet
,C. 10 feet
D. 15 feet
Answer: C. 10 feet
Rationale: NEC 760.41(B) requires that the disconnecting means for a fire alarm
control panel be located within 10 feet of the panel and be readily accessible. This
ensures rapid power isolation during emergencies.**
Question 3
Which of the following is the maximum allowable resistance for a ground rod
electrode installed in a low-voltage system?
A. 5 ohms
B. 10 ohms
C. 25 ohms
D. 50 ohms
Answer: C. 25 ohms
Rationale: NEC 250.53(A)(2) requires that a single ground rod electrode have a
resistance to ground of 25 ohms or less. If resistance exceeds this, a second rod
must be installed or additional measures taken.**
Question 4
When terminating a shielded twisted-pair (STP) cable, where should the drain
wire be connected?
A. To the equipment ground at both ends
B. To the equipment ground at the patch panel only
C. To the equipment ground at the device end only
D. To a floating ground terminal
Answer: B. To the equipment ground at the patch panel only
Rationale: For STP cables, the drain wire should be grounded at the patch panel
(building ground) and left ungrounded at the device end to prevent ground loops,
which can introduce hum or noise in sensitive audio/video applications.**
,Question 5
What is the minimum insulation resistance test voltage for a 120V low-voltage
control circuit according to NETA standards?
A. 250V DC
B. 500V DC
C. 1000V DC
D. 1500V DC
Answer: B. 500V DC
Rationale: NETA ATS Table 100.1 specifies that insulation resistance testing for
circuits rated 250V or less should be performed at 500V DC. This provides a valid
indication of insulation integrity without overstressing low-voltage components.**
Question 6
In a Class 2 power-limited fire alarm system, what is the maximum output power
permitted per NEC?
A. 50 VA
B. 75 VA
C. 100 VA
D. 150 VA
Answer: C. 100 VA
Rationale: NEC 725.121(A) limits Class 2 power supplies to 100 VA maximum
output. This ensures the circuit is inherently limited and reduces fire and shock
hazards.**
Question 7
Which color pair is assigned to the first pair in a T568B wiring scheme for an 8P8C
(RJ45) connector?
A. Blue/White
B. Orange/White
, C. Green/White
D. Brown/White
Answer: B. Orange/White
Rationale: T568B uses the orange/white pair (pins 1-2) as Pair 1, green/white
(pins 3-6) as Pair 2, blue/white (pins 4-5) as Pair 3, and brown/white (pins 7-8) as
Pair 4.**
Question 8
A low-voltage technician is installing a CCTV system with 24V AC cameras. What is
the maximum recommended voltage drop for the power feeder?
A. 2%
B. 3%
C. 5%
D. 10%
Answer: C. 5%
Rationale: For low-voltage AC power distribution, a 5% voltage drop is typically
the maximum allowed to ensure proper camera operation. Many manufacturers
specify a tolerance of ±10%, but 5% is a conservative best practice.**
Question 9
What type of fire-rated cable is required for a circuit that must maintain operation
for 2 hours during a fire?
A. FPLP
B. FPLR
C. CI-Cable
D. CMP
Answer: C. CI-Cable
Rationale: Circuit Integrity (CI) cable, per NEC 760.176(F), is rated for 2-hour fire
survival. FPLP is plenum-rated but not fire-survival, FPLR is riser-rated, and CMP is
communications plenum cable.**
