VOICE DATA VIDEO VDV EVALUATION EXAM 2025
QUESTIONS WITH SOLUTIONS RATED A+
✔✔An electrical power system is a system that ____ and delivers electrical power to
satisfactorily operate electrical loads designed for connection to a system.
a. distributes
b. produces
c. transmits
d. all of the above - ✔✔d. all of the above
✔✔T/F
A preventative maintenance program is a combination of unscheduled and scheduled
maintenance work required to maintain equipment in peak operating condition. -
✔✔True
✔✔Why is it preferable to acquire power quality measurements over time?
a. Power quality problems are only detectable at certain times of the day.
b. Power quality problems occur during a certain sequence of production operations.
c. Power quality problems vary over time.
d. All of the above - ✔✔d. All of the above
✔✔___ is a logical, step-by-step process used to find a problem in an electrical power
system or process as quickly and easily as possible.
a. Preventive maintenance
b. Relay Logic
c. Shotgun approach
d. Troubleshooting - ✔✔d. Troubleshooting
✔✔Which of the following is a linear load?
a. Computer
b. Copy machine
c. Electric motor drive
d. Incandescent lamp - ✔✔d. Incandescent lamp
✔✔Nonlinear loads are a common source of ___ problems.
a. harmonic
b. noise
c. sags
d. transients - ✔✔a. harmonic
✔✔T/F
Starting large three-phase motors or equipment causes voltage swells. - ✔✔False
✔✔T/F
, Improper phase sequence (phase reversal) is the changing of the sequence of any two
phases in a three-phase system or circuit. Improper phase sequence reverses motor
rotation. - ✔✔True
✔✔T/F
A neutral conductor is a current-carrying conductor that is connected to loads through
fuses, circuit breakers, and switches - ✔✔False
✔✔Phase unbalance causes three-phase motors to operate at temperatures ___and,
therefore, the motor cannot deliver its rated horsepower.
a. below ambient
b. higher than nameplate ratings
c. lower than nameplate ratings
d. similar to full load current ratings - ✔✔b. higher than nameplate ratings
✔✔How are power lines balanced when they are more than 3% out of phase?
a. After balancing the loads, re-test the phases for proper phase balance with a power
analyzer meter.
b. Take current measurements on all the single-phase power lines (use a clamp-on
ammeter).
c. When one or two power lines are overloaded, remove the load from the overloaded
line and placethe load on a line that is not overloaded.
d. All of the above - ✔✔d. All of the above
✔✔T/F
When voltage unbalance improves as loads are removed, the problem is inside the
facility. - ✔✔True
✔✔The primary source of voltage unbalance that is less than 2% is ? load(s) on a three-
phase circuit
a. capacitive
b. more than one three-phase
c. resistive three-phase
d. single-phase - ✔✔d. single-phase
✔✔Which of the following is not a common cause of single-phasing?
a. Blown fuses
b. Harmonic distortion
c. Lightning strike on one of the power lines [Use as written]
d. Mechanical failure within switching equipment - ✔✔b. Harmonic distortion
✔✔To test for a motor that is single-phasing, both ___and___measurements must be
taken, which are best performed while the motor is running.
a. resistance / current
QUESTIONS WITH SOLUTIONS RATED A+
✔✔An electrical power system is a system that ____ and delivers electrical power to
satisfactorily operate electrical loads designed for connection to a system.
a. distributes
b. produces
c. transmits
d. all of the above - ✔✔d. all of the above
✔✔T/F
A preventative maintenance program is a combination of unscheduled and scheduled
maintenance work required to maintain equipment in peak operating condition. -
✔✔True
✔✔Why is it preferable to acquire power quality measurements over time?
a. Power quality problems are only detectable at certain times of the day.
b. Power quality problems occur during a certain sequence of production operations.
c. Power quality problems vary over time.
d. All of the above - ✔✔d. All of the above
✔✔___ is a logical, step-by-step process used to find a problem in an electrical power
system or process as quickly and easily as possible.
a. Preventive maintenance
b. Relay Logic
c. Shotgun approach
d. Troubleshooting - ✔✔d. Troubleshooting
✔✔Which of the following is a linear load?
a. Computer
b. Copy machine
c. Electric motor drive
d. Incandescent lamp - ✔✔d. Incandescent lamp
✔✔Nonlinear loads are a common source of ___ problems.
a. harmonic
b. noise
c. sags
d. transients - ✔✔a. harmonic
✔✔T/F
Starting large three-phase motors or equipment causes voltage swells. - ✔✔False
✔✔T/F
, Improper phase sequence (phase reversal) is the changing of the sequence of any two
phases in a three-phase system or circuit. Improper phase sequence reverses motor
rotation. - ✔✔True
✔✔T/F
A neutral conductor is a current-carrying conductor that is connected to loads through
fuses, circuit breakers, and switches - ✔✔False
✔✔Phase unbalance causes three-phase motors to operate at temperatures ___and,
therefore, the motor cannot deliver its rated horsepower.
a. below ambient
b. higher than nameplate ratings
c. lower than nameplate ratings
d. similar to full load current ratings - ✔✔b. higher than nameplate ratings
✔✔How are power lines balanced when they are more than 3% out of phase?
a. After balancing the loads, re-test the phases for proper phase balance with a power
analyzer meter.
b. Take current measurements on all the single-phase power lines (use a clamp-on
ammeter).
c. When one or two power lines are overloaded, remove the load from the overloaded
line and placethe load on a line that is not overloaded.
d. All of the above - ✔✔d. All of the above
✔✔T/F
When voltage unbalance improves as loads are removed, the problem is inside the
facility. - ✔✔True
✔✔The primary source of voltage unbalance that is less than 2% is ? load(s) on a three-
phase circuit
a. capacitive
b. more than one three-phase
c. resistive three-phase
d. single-phase - ✔✔d. single-phase
✔✔Which of the following is not a common cause of single-phasing?
a. Blown fuses
b. Harmonic distortion
c. Lightning strike on one of the power lines [Use as written]
d. Mechanical failure within switching equipment - ✔✔b. Harmonic distortion
✔✔To test for a motor that is single-phasing, both ___and___measurements must be
taken, which are best performed while the motor is running.
a. resistance / current
