SkilledTradesBC Electrical Level 3 Exam
Questions with Correct Answers
(VerifiedAnswers) Plus Rationales 2026 Q&A
Instant Download PDF
Question 1
A 120 V single-phase load draws 15 A. What is the approximate
power consumed by the load?
A. 1,200 W
B. 1,500 W
C. 1,800 W
D. 2,400 W
Rationale: For a basic resistive load, power is calculated using P
= V × I. Substituting 120 V and 15 A gives 120 × 15 = 1,800 W.
This relationship is fundamental when determining circuit
loading and assessing whether conductors and overcurrent
protection are suitable for the connected load.
Question 2
,What is the primary purpose of a circuit breaker in an electrical
installation?
A. To increase circuit voltage
B. To improve power factor
C. To interrupt current when an overcurrent condition occurs
D. To provide a continuous neutral connection
Rationale: A circuit breaker is an overcurrent protective device.
Its function is to open the circuit when current exceeds the
permitted level for the circuit conditions. This helps protect
conductors and associated equipment from damage caused by
overloads or short circuits.
Question 3
In a parallel circuit, what happens to the voltage across each
properly connected branch?
A. It is divided equally between all branches
B. It becomes zero at the last branch
C. It depends only on the resistance of the first branch
D. It is approximately equal to the source voltage
Rationale: Parallel branches are connected across the same two
electrical points. Consequently, each branch experiences
essentially the same applied voltage. Current, rather than
,voltage, divides among the branches according to their
individual impedances or resistances.
Question 4
Which instrument should normally be connected in parallel
when measuring voltage?
A. Ammeter
B. Clamp meter only
C. Voltmeter
D. Watt-hour meter
Rationale: A voltmeter measures the potential difference
between two points, so it is connected across the component or
portion of the circuit being tested. A conventional ammeter, by
contrast, is connected in series because it measures current
flowing through the circuit.
Question 5
A circuit has a resistance of 24 Ω and is supplied at 120 V. What
current should be expected?
A. 2 A
B. 4 A
, C. 5 A
D. 20 A
Rationale: Ohm's law states that I = V/R. Therefore, I = 120/24 =
5 A. Correctly applying Ohm's law is essential for
troubleshooting circuits, checking expected current draw, and
identifying abnormal operating conditions.
Question 6
What is the main purpose of bonding electrically conductive
non-current-carrying metal parts?
A. To increase operating voltage
B. To reduce normal load current
C. To provide a low-impedance path for fault current
D. To eliminate the need for overcurrent protection
Rationale: Bonding connects exposed conductive parts so that,
under fault conditions, a sufficiently low-impedance path is
available for fault current. This assists protective devices in
operating promptly and reduces the likelihood that exposed
metal remains at a dangerous voltage.
Question 7
Questions with Correct Answers
(VerifiedAnswers) Plus Rationales 2026 Q&A
Instant Download PDF
Question 1
A 120 V single-phase load draws 15 A. What is the approximate
power consumed by the load?
A. 1,200 W
B. 1,500 W
C. 1,800 W
D. 2,400 W
Rationale: For a basic resistive load, power is calculated using P
= V × I. Substituting 120 V and 15 A gives 120 × 15 = 1,800 W.
This relationship is fundamental when determining circuit
loading and assessing whether conductors and overcurrent
protection are suitable for the connected load.
Question 2
,What is the primary purpose of a circuit breaker in an electrical
installation?
A. To increase circuit voltage
B. To improve power factor
C. To interrupt current when an overcurrent condition occurs
D. To provide a continuous neutral connection
Rationale: A circuit breaker is an overcurrent protective device.
Its function is to open the circuit when current exceeds the
permitted level for the circuit conditions. This helps protect
conductors and associated equipment from damage caused by
overloads or short circuits.
Question 3
In a parallel circuit, what happens to the voltage across each
properly connected branch?
A. It is divided equally between all branches
B. It becomes zero at the last branch
C. It depends only on the resistance of the first branch
D. It is approximately equal to the source voltage
Rationale: Parallel branches are connected across the same two
electrical points. Consequently, each branch experiences
essentially the same applied voltage. Current, rather than
,voltage, divides among the branches according to their
individual impedances or resistances.
Question 4
Which instrument should normally be connected in parallel
when measuring voltage?
A. Ammeter
B. Clamp meter only
C. Voltmeter
D. Watt-hour meter
Rationale: A voltmeter measures the potential difference
between two points, so it is connected across the component or
portion of the circuit being tested. A conventional ammeter, by
contrast, is connected in series because it measures current
flowing through the circuit.
Question 5
A circuit has a resistance of 24 Ω and is supplied at 120 V. What
current should be expected?
A. 2 A
B. 4 A
, C. 5 A
D. 20 A
Rationale: Ohm's law states that I = V/R. Therefore, I = 120/24 =
5 A. Correctly applying Ohm's law is essential for
troubleshooting circuits, checking expected current draw, and
identifying abnormal operating conditions.
Question 6
What is the main purpose of bonding electrically conductive
non-current-carrying metal parts?
A. To increase operating voltage
B. To reduce normal load current
C. To provide a low-impedance path for fault current
D. To eliminate the need for overcurrent protection
Rationale: Bonding connects exposed conductive parts so that,
under fault conditions, a sufficiently low-impedance path is
available for fault current. This assists protective devices in
operating promptly and reduces the likelihood that exposed
metal remains at a dangerous voltage.
Question 7
