Module 2 Flashcards
a device that can store electrical charge
Capacitor
a capacitor motor having two different values of capacitance
Two-value capacitor motor
a capacitor motor having only one value of capacitance
Single-value capacitor motor
A(n) _____ is a device that can store electrical charge.
Capacitor
What kind of capacitor has polarity markings, and must not be used in ac circuits?
Electrolytic
A split-phase motor can be made to run as a capacitor-start motor by connecting a capacitor in _____ with the _____ winding.
Series; Start
A(n) _____ must be established in a capacitor-start motor to produce the starting torque.
Rotating magnetic field
In a split-phase motor, the start-winding current ____ the run-winding current, but it _____ the applied potential difference.
Leads: Lags
What device in a power line is the short-circuit protective device for a motor?
Fuse or Circuit Breaker
A dual-voltage motor can operate on either _____ V or _____ V.
120; 240
A capacitor-start capacitor-run motor having two different values of capacitance is called a(n) _____ motor.
Tow-value capacitor
A permanent-split capacitor motor has a(n) _____ instead of a centrifugal switch.
Low-value capacitor
A reversible capacitor-run motor will not start without a capacitor in the circuit, because the windings are _____.
Identical
Decreasing the rotor speed in a two-speed capacitor-run motor is accomplished by adding a(n) _____.
Auxiliary winding
A short circuit occurs in a capacitor when the _____ material breaks down.
Dielectric
Before disconnecting a capacitor from a motor, you must disconnect the _____.
Power supply
Smoke from a motor may be caused by _____, _____, or ______.
Overload
Shorted windings
Faulty centrifugal switch
If necessary, you can substitute by using a capacitor with a _____ voltage rating than the original
Higher
If one capacitor in a two-capacitor motor is defective, should you replace both capacitor or only the bad one?
Both
A capacitor is made to _____ an electric charge.
Store
If you suspect a capacitor is defective, what should you do before you test it?
a. discharge the capacitor through a resistor
b. disconnect the capacitor leads
c. disconnect the power supply
d. all of the above
d. all of the above
A capacitor for use in a 120V motor must be rated for _____ V.
a. 75 to 130
b. 130 to 150
c. 175 to 225
d. 250 to 300
b. 130 to 150
If a capacitor motor has difficulty starting or has poor starting torque, the trouble may be
loose rotor bars
A split-phase motor can be made to run as a capacitor-start motor by connecting a capacitor in _____ with the _____ winding.
series; start
If you must substitute one capacitor for another, the best choice is one with a
higher voltage rating.
Which of the following provide(s) thermal overload protection in some capacitor-start motors?
Bimetallic strip
Two 100 uF capacitors connected in series have a combined capacitance of _____ uF.
50
What is the purpose of the capacitor in a reversible capacitor-run motor?
a. to change the phase angle.
Two 120 V capacitors connected in series have a combined voltage rating of _____ V.
240
