CFESA ELECTRICAL PRACTICE TEST
ACTUAL EXAM QUESTIONS AND
CORRECT DETAILED ANSWERS
How does a GFCI operate? - ✔✔✔ Correct Answer > It compares amperage out
of the breaker on the hotline and compares it to the return current on the neutral
if the difference exceeds 5 mA it tripped the breaker off
Advantage of a breaker over a fuse - ✔✔✔ Correct Answer > Can reset
Weak circuit breakers are a result of - ✔✔✔ Correct Answer > Overheating bad
wire connections on the breaker using the breaker for a switch
7 why is it not advisable just to replace a coil in the contactor when the coil fails
even if it is available as a separate replacement part - ✔✔✔ Correct Answer >
Will fail again soon
11 do contractor contacts that look dark in color necessarily mean the contactor
needs to be replaced - ✔✔✔ Correct Answer > No
12. Do contacts that look like they have rough surfaces indicate that the
contact should be replaced. - ✔✔✔ Correct Answer > No
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,13. What will contact look like in a contactor when the contactor should be
replaced? - ✔✔✔ Correct Answer > Worn thin or cratered out
16. How do you check a contactor coil to ensure that it's all right -
✔✔✔ Correct Answer > Om it with a meter and compare it to a chart or to an
exact duplicate contactor
17. When they contacter buzzes when it is energized, what is the problem? -
✔✔✔ Correct Answer > Worn, the armature is not pulling down tightly
18. When they contact the chatters one energize, what is the problem? -
✔✔✔ Correct Answer > the controls
19 will replacing a chattering contact or solved the problem - ✔✔✔ Correct
Answer > No
20. What can be used to eliminate chattering problem in a contactor? - ✔✔✔
Correct Answer > A capacitor across the contractor coil
What is the switch arrangement on a Robertshaw EA thermostat? - ✔✔✔
Correct Answer > SPST
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, What is a PSC motor? - ✔✔✔ Correct Answer > Permanent Split
Capacitor
What are the 3 different kinds of temperature sensors that can be used with a
solid state control? - ✔✔✔ Correct Answer > Thermocouple, thermistor, and
RTD.
Why are thermistors the most popular of all the temperature sensors? - ✔✔✔
Correct Answer > less expensive
What is the major downfall of a single probe electro mechanical liquid level
control? - ✔✔✔ Correct Answer > Fast cycling as soon as the water uncovers
the probe.
Contacts that are melted or welded together indicate what? - ✔✔✔ Correct
Answer > short circuit
6 What is the usual cause for a burned out contactor coil? - ✔✔✔
Correct Answer > Warped movable contact carried
What causes carbon build up around the body of a contactor? - ✔✔✔ Correct
Answer > Arcing
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ACTUAL EXAM QUESTIONS AND
CORRECT DETAILED ANSWERS
How does a GFCI operate? - ✔✔✔ Correct Answer > It compares amperage out
of the breaker on the hotline and compares it to the return current on the neutral
if the difference exceeds 5 mA it tripped the breaker off
Advantage of a breaker over a fuse - ✔✔✔ Correct Answer > Can reset
Weak circuit breakers are a result of - ✔✔✔ Correct Answer > Overheating bad
wire connections on the breaker using the breaker for a switch
7 why is it not advisable just to replace a coil in the contactor when the coil fails
even if it is available as a separate replacement part - ✔✔✔ Correct Answer >
Will fail again soon
11 do contractor contacts that look dark in color necessarily mean the contactor
needs to be replaced - ✔✔✔ Correct Answer > No
12. Do contacts that look like they have rough surfaces indicate that the
contact should be replaced. - ✔✔✔ Correct Answer > No
Page 1 of 29
,13. What will contact look like in a contactor when the contactor should be
replaced? - ✔✔✔ Correct Answer > Worn thin or cratered out
16. How do you check a contactor coil to ensure that it's all right -
✔✔✔ Correct Answer > Om it with a meter and compare it to a chart or to an
exact duplicate contactor
17. When they contacter buzzes when it is energized, what is the problem? -
✔✔✔ Correct Answer > Worn, the armature is not pulling down tightly
18. When they contact the chatters one energize, what is the problem? -
✔✔✔ Correct Answer > the controls
19 will replacing a chattering contact or solved the problem - ✔✔✔ Correct
Answer > No
20. What can be used to eliminate chattering problem in a contactor? - ✔✔✔
Correct Answer > A capacitor across the contractor coil
What is the switch arrangement on a Robertshaw EA thermostat? - ✔✔✔
Correct Answer > SPST
Page 2 of 29
, What is a PSC motor? - ✔✔✔ Correct Answer > Permanent Split
Capacitor
What are the 3 different kinds of temperature sensors that can be used with a
solid state control? - ✔✔✔ Correct Answer > Thermocouple, thermistor, and
RTD.
Why are thermistors the most popular of all the temperature sensors? - ✔✔✔
Correct Answer > less expensive
What is the major downfall of a single probe electro mechanical liquid level
control? - ✔✔✔ Correct Answer > Fast cycling as soon as the water uncovers
the probe.
Contacts that are melted or welded together indicate what? - ✔✔✔ Correct
Answer > short circuit
6 What is the usual cause for a burned out contactor coil? - ✔✔✔
Correct Answer > Warped movable contact carried
What causes carbon build up around the body of a contactor? - ✔✔✔ Correct
Answer > Arcing
Page 3 of 29
