electrical final year 4a|140 questions
with correct answers latest 2025/26.
What is the feeder ampacity for a three-phase, 120/208V subpanel with a connected
load of 84,563VA? - Answer235A
The demand lighting load for a 20,000 ft2 motel with no dining room or ballroom is
_____. - Answer19,000VA
When making service calculations for multi-family dwellings, additional demand factors
may be applied to the portion of the neutral load greater than _____. - Answer200A
What is the demand factor allowed by the NEC® for calculating the neutral conductor
size for an electric range load? - Answer70%
Refer to the figure provided. What is the total load a feeder serving four 2hp motors,
three 5hp motors, one 15hp motor, and one 25hp motor? (All motors are 208V.) -
Answer219.8A
What is another name given to solid-state, reduced-voltage starters because of their
ability to provide a smoother, stepless start and acceleration? - AnswerSoft-start
controllers
Which of the following protect the motor against overheating? - AnswerSolid-state
overload relays
Most NEMA-rated general purpose motors have an overcurrent trip class rating of
_____. - AnswerClass 20
A small imbalance in phase-to-phase voltage can result in _____. -
Answerincreased heat generated in motor windings
Which type of braking system relies on brake shoes and pads? - AnswerFriction
braking
For the AFD operating frequency range shown in the figure provided, the range of
output frequencies over which the AFD output voltage remains constant while the
frequency varies is _____. - AnswerB to C
, When troubleshooting a motor, one possible cause of constant chatter is _____. -
Answera broken pole shader
In a constant-horsepower load, the torque _____. - Answerdecreases as the speed
increases
One advantage of DC injection braking is that _____. - Answerthe motor can be
stopped without having wear on brake linings or drums
Over time, the formation of normal oxides may turn the color of contacts _____. -
Answerblack
When contacts are new, they have a uniform _____. - Answersilver
In a typical DC injection braking circuit, power is supplied to the braking relay by _____.
- AnswerNOTO contacts
Which symbol in the figure provided represents a normally open, timed-open (NOTO)
contact of a timing relay? - AnswerFigure C
The amount of braking torque when using DC braking of an AC motor can be controlled
by using a tapped transformer or by _____. - Answeradding a current-limiting
resistor
Grounding wrist straps are used to _____. - Answerprevent static discharge from
damaging solid-state circuits
When measuring the resistance of a contactor coil, a reading of zero indicates _____. -
Answera shorted coil
The contactor sequence for the circuit shown in the figure provided is such that during
the transition from reduced-voltage operation to full-voltage operation, the energized
contactors are 2S and _____. - AnswerR
The purpose of contactor 2M shown in the figure provided is to _____. -
Answerenergize motor leads T4, T5, and T6 during running to connect the motor
windings in a delta configuration
One of the advantages of an SSR over an EMR is its _____. - Answerresponse time
with correct answers latest 2025/26.
What is the feeder ampacity for a three-phase, 120/208V subpanel with a connected
load of 84,563VA? - Answer235A
The demand lighting load for a 20,000 ft2 motel with no dining room or ballroom is
_____. - Answer19,000VA
When making service calculations for multi-family dwellings, additional demand factors
may be applied to the portion of the neutral load greater than _____. - Answer200A
What is the demand factor allowed by the NEC® for calculating the neutral conductor
size for an electric range load? - Answer70%
Refer to the figure provided. What is the total load a feeder serving four 2hp motors,
three 5hp motors, one 15hp motor, and one 25hp motor? (All motors are 208V.) -
Answer219.8A
What is another name given to solid-state, reduced-voltage starters because of their
ability to provide a smoother, stepless start and acceleration? - AnswerSoft-start
controllers
Which of the following protect the motor against overheating? - AnswerSolid-state
overload relays
Most NEMA-rated general purpose motors have an overcurrent trip class rating of
_____. - AnswerClass 20
A small imbalance in phase-to-phase voltage can result in _____. -
Answerincreased heat generated in motor windings
Which type of braking system relies on brake shoes and pads? - AnswerFriction
braking
For the AFD operating frequency range shown in the figure provided, the range of
output frequencies over which the AFD output voltage remains constant while the
frequency varies is _____. - AnswerB to C
, When troubleshooting a motor, one possible cause of constant chatter is _____. -
Answera broken pole shader
In a constant-horsepower load, the torque _____. - Answerdecreases as the speed
increases
One advantage of DC injection braking is that _____. - Answerthe motor can be
stopped without having wear on brake linings or drums
Over time, the formation of normal oxides may turn the color of contacts _____. -
Answerblack
When contacts are new, they have a uniform _____. - Answersilver
In a typical DC injection braking circuit, power is supplied to the braking relay by _____.
- AnswerNOTO contacts
Which symbol in the figure provided represents a normally open, timed-open (NOTO)
contact of a timing relay? - AnswerFigure C
The amount of braking torque when using DC braking of an AC motor can be controlled
by using a tapped transformer or by _____. - Answeradding a current-limiting
resistor
Grounding wrist straps are used to _____. - Answerprevent static discharge from
damaging solid-state circuits
When measuring the resistance of a contactor coil, a reading of zero indicates _____. -
Answera shorted coil
The contactor sequence for the circuit shown in the figure provided is such that during
the transition from reduced-voltage operation to full-voltage operation, the energized
contactors are 2S and _____. - AnswerR
The purpose of contactor 2M shown in the figure provided is to _____. -
Answerenergize motor leads T4, T5, and T6 during running to connect the motor
windings in a delta configuration
One of the advantages of an SSR over an EMR is its _____. - Answerresponse time
