IEC FINAL EXAM 2026/2027 | COMPLETE QUESTIONS AND
ANSWERS (VERIFIED ANSWERS) | EXAM PREP | LATEST EXAM
GUIDE 2026&2027
1. A residential lighting circuit is being wired so that the switch interrupts the energized
conductor supplying the luminaire. Which conductor should be connected to the switch
first?
A. Grounding conductor
B. Ungrounded conductor
C. Grounded conductor
D. Bonding jumper
Answer: B
The switch should interrupt the ungrounded conductor so that the controlled equipment is de-
energized when the switch is open.
2. An electrician needs to control one lighting load from a single location. Which switch is
normally appropriate?
A. Four-way switch
B. Three-way switch
C. Single-pole switch
D. Double-pole three-way switch
Answer: C
A single-pole switch is designed to control a load from one location.
3. A technician is converting a standard duplex receptacle into a split-wired receptacle.
What must normally be removed on the brass-side terminal connection?
A. Grounding screw
B. Neutral terminal
C. Mounting screw
D. Break-off tab
Answer: D
Removing the appropriate break-off tab separates the two receptacle sections so they can be
supplied independently.
,4. A 120-volt branch circuit has a white insulated conductor serving as the grounded
conductor. Which term correctly describes this conductor?
A. Neutral or grounded conductor
B. Ungrounded conductor
C. Equipment grounding conductor
D. Bonding conductor
Answer: A
The grounded conductor of a typical 120-volt circuit is commonly referred to as the neutral
conductor.
5. An electrician measures 2,400 watts on a 240-volt single-phase load. Approximately how
much current does the load draw?
A. 5 A
B. 8 A
C. 10 A
D. 20 A
Answer: C
Using I = P/E, the current is 2,400 ÷ 240 = 10 amperes.
6. During troubleshooting, an electrician discovers that a circuit breaker trips immediately
when a load is connected. What should be investigated first?
A. Paint color of the enclosure
B. Possible short circuit or ground fault
C. Conduit support spacing only
D. Labeling of unrelated circuits
Answer: B
An immediate trip commonly indicates a fault condition such as a short circuit or ground fault
that should be safely identified before re-energizing the circuit.
7. Which device is specifically designed to provide protection against ground-fault shock
hazards in applicable locations?
A. Standard toggle switch
B. Isolating transformer
C. Surge protector
D. GFCI
,Answer: D
A ground-fault circuit-interrupter detects an imbalance in current and rapidly interrupts the
circuit when its trip conditions are met.
8. An electrician is selecting a circuit breaker for equipment with a calculated maximum
continuous load. Which principle is most important?
A. The overcurrent device must be selected according to the applicable load and code
requirements
B. The breaker should always be exactly equal to the conductor's physical diameter
C. The breaker rating should always be twice the calculated load
D. The breaker should be selected only by the equipment color
Answer: A
Overcurrent protection must be coordinated with the calculated load, conductor ampacity,
equipment requirements, and applicable code provisions.
9. What is the primary purpose of an equipment grounding conductor?
A. Carry normal neutral current
B. Increase operating voltage
C. Provide a low-impedance fault-current path
D. Replace the circuit overcurrent device
Answer: C
The equipment grounding conductor provides a conductive path intended to facilitate
operation of the protective device during a fault.
10. A receptacle is installed outdoors where it may be exposed to rain. Which consideration
is most important?
A. Use only an indoor-rated cover
B. Provide equipment suitable for the environmental conditions
C. Remove the grounding connection
D. Install the receptacle without a box
Answer: B
Outdoor installations require equipment and protection suitable for exposure to moisture and
the specific environmental conditions.
11. Which abbreviation represents single-pole, single-throw?
, A. SPST
B. DPST
C. SPDT
D. DPDT
Answer: A
SPST stands for single-pole, single-throw and is commonly used for simple on/off switching
from one location.
12. An electrician must control one light from two different locations, such as the two ends
of a hallway. Which switching arrangement is appropriate?
A. Two single-pole switches
B. One four-way switch only
C. Two three-way switches
D. One double-pole switch
Answer: C
Two three-way switches are used to control a lighting load from two locations.
13. A long hallway requires control of one light from three locations. What arrangement is
normally used?
A. Three single-pole switches
B. Two three-way switches with one four-way switch
C. One three-way switch only
D. Two four-way switches without three-way switches
Answer: B
A four-way switch is installed between two three-way switches to provide control from three
locations.
14. A conductor's insulation has been damaged and bare copper is exposed inside a metal
box. What is the safest action?
A. Cover it with paint
B. Ignore it if the circuit works
C. Replace or properly repair the damaged conductor
D. Increase the breaker size
Answer: C
ANSWERS (VERIFIED ANSWERS) | EXAM PREP | LATEST EXAM
GUIDE 2026&2027
1. A residential lighting circuit is being wired so that the switch interrupts the energized
conductor supplying the luminaire. Which conductor should be connected to the switch
first?
A. Grounding conductor
B. Ungrounded conductor
C. Grounded conductor
D. Bonding jumper
Answer: B
The switch should interrupt the ungrounded conductor so that the controlled equipment is de-
energized when the switch is open.
2. An electrician needs to control one lighting load from a single location. Which switch is
normally appropriate?
A. Four-way switch
B. Three-way switch
C. Single-pole switch
D. Double-pole three-way switch
Answer: C
A single-pole switch is designed to control a load from one location.
3. A technician is converting a standard duplex receptacle into a split-wired receptacle.
What must normally be removed on the brass-side terminal connection?
A. Grounding screw
B. Neutral terminal
C. Mounting screw
D. Break-off tab
Answer: D
Removing the appropriate break-off tab separates the two receptacle sections so they can be
supplied independently.
,4. A 120-volt branch circuit has a white insulated conductor serving as the grounded
conductor. Which term correctly describes this conductor?
A. Neutral or grounded conductor
B. Ungrounded conductor
C. Equipment grounding conductor
D. Bonding conductor
Answer: A
The grounded conductor of a typical 120-volt circuit is commonly referred to as the neutral
conductor.
5. An electrician measures 2,400 watts on a 240-volt single-phase load. Approximately how
much current does the load draw?
A. 5 A
B. 8 A
C. 10 A
D. 20 A
Answer: C
Using I = P/E, the current is 2,400 ÷ 240 = 10 amperes.
6. During troubleshooting, an electrician discovers that a circuit breaker trips immediately
when a load is connected. What should be investigated first?
A. Paint color of the enclosure
B. Possible short circuit or ground fault
C. Conduit support spacing only
D. Labeling of unrelated circuits
Answer: B
An immediate trip commonly indicates a fault condition such as a short circuit or ground fault
that should be safely identified before re-energizing the circuit.
7. Which device is specifically designed to provide protection against ground-fault shock
hazards in applicable locations?
A. Standard toggle switch
B. Isolating transformer
C. Surge protector
D. GFCI
,Answer: D
A ground-fault circuit-interrupter detects an imbalance in current and rapidly interrupts the
circuit when its trip conditions are met.
8. An electrician is selecting a circuit breaker for equipment with a calculated maximum
continuous load. Which principle is most important?
A. The overcurrent device must be selected according to the applicable load and code
requirements
B. The breaker should always be exactly equal to the conductor's physical diameter
C. The breaker rating should always be twice the calculated load
D. The breaker should be selected only by the equipment color
Answer: A
Overcurrent protection must be coordinated with the calculated load, conductor ampacity,
equipment requirements, and applicable code provisions.
9. What is the primary purpose of an equipment grounding conductor?
A. Carry normal neutral current
B. Increase operating voltage
C. Provide a low-impedance fault-current path
D. Replace the circuit overcurrent device
Answer: C
The equipment grounding conductor provides a conductive path intended to facilitate
operation of the protective device during a fault.
10. A receptacle is installed outdoors where it may be exposed to rain. Which consideration
is most important?
A. Use only an indoor-rated cover
B. Provide equipment suitable for the environmental conditions
C. Remove the grounding connection
D. Install the receptacle without a box
Answer: B
Outdoor installations require equipment and protection suitable for exposure to moisture and
the specific environmental conditions.
11. Which abbreviation represents single-pole, single-throw?
, A. SPST
B. DPST
C. SPDT
D. DPDT
Answer: A
SPST stands for single-pole, single-throw and is commonly used for simple on/off switching
from one location.
12. An electrician must control one light from two different locations, such as the two ends
of a hallway. Which switching arrangement is appropriate?
A. Two single-pole switches
B. One four-way switch only
C. Two three-way switches
D. One double-pole switch
Answer: C
Two three-way switches are used to control a lighting load from two locations.
13. A long hallway requires control of one light from three locations. What arrangement is
normally used?
A. Three single-pole switches
B. Two three-way switches with one four-way switch
C. One three-way switch only
D. Two four-way switches without three-way switches
Answer: B
A four-way switch is installed between two three-way switches to provide control from three
locations.
14. A conductor's insulation has been damaged and bare copper is exposed inside a metal
box. What is the safest action?
A. Cover it with paint
B. Ignore it if the circuit works
C. Replace or properly repair the damaged conductor
D. Increase the breaker size
Answer: C
