Unit 18. Single Phase Motors

A. synchronous speed

In a motor that has a rotating magnetic field, the speed of that magnetic field is referred to as the _____. A. synchronous speed B. rotor speed C. slip speed D. stator speed

A. AC only

In a universal motor, inductive compensation can be used when the motor is connected to _____. A. AC only B. either AC or DC C. DC only

B. centrifugal switch

In single-phase motors such as the resistance start induction-run motor, the start winding is disconnected by the _____. A. overload switch B. centrifugal switch C. disconnect switch D. operator

C. rotating

Split-phase motors operate on the principle of a _____ magnetic field. A. vibrating B. pulsating C. rotating D. fixed

D. 1200

The Holtz motor operates at _____ RPM. A. 1800 B. 1725 C. 3600 D. 1200

B. 3600

The Warren motor operates at _____ RPM. A. 1800 B. 3600 C. 1725 D. 1200

D. universal

The _____ motor can operate on either AC or DC voltage. A. split-phase B. consequent pole C. shaded pole D. universal

A. compensating winding

The universal motor has a wound armature and brushes like an AC motor, as well as an added component, the _____. A. compensating winding B. inductive winding C. neutral plane D. synchronous winding

A. hysteresis

A single-phase synchronous motor is sometimes referred to as a(n) _____ motor. A. hysteresis B. impedance C. inductive D. repulsion

C. 90°

A two-phase power system has two voltages that are _____ out of phase. A. 60° B. 180° C. 90° D. 360°

D. repulsion

A(n) _____ motor operates on the principle that like magnetic poles repel. A. impedance B. hysteresis C. inductive D. repulsion

B. series

Conductive compensation is accomplished by connecting the compensating winding in _____ with the armature. A. parallel B. series

B. minimum

In a universal motor, setting the brushes to the neutral plane can be done by connecting voltage to the armature, a voltmeter to the series field, and adjusting the brush position for a _____ reading on the voltmeter. A. maximum B. minimum

D. run

The _____ winding is made of a few turns of large wire and is located at the bottom of the stator core of a split-phase motor. A. synchronous B. start C. disconnect D. run

A. start

The _____ winding is made of many turns of small wire and is located at the top of the stator core of a split-phase motor. A. start B. run C. synchronous D. disconnect

A. high

The consequent-pole motor is used where _____ running torque must be maintained at different speeds. A. high B. low

C. moves through a specific angle for each input pulse

The output shaft of a stepping motor _____. A. rotates at a constant speed during each input pulse B. steps continuously when power is applied C. moves through a specific angle for each input pulse D. rotates continuously when power is applied

C. torque motor

What is a special type of motor designed to operate with the rotor stalled without damage to the motor? A. servo motor ​B. repulsion motor C. torque motor ​D. capacitor-start capacitor-run motor

B. magnetic field strength

In the shaded-pole induction motor, the direction of rotation of the magnetic field is determined by the _____. A. You Answered shading coil diameter B. magnetic field strength C. generator power D. rotor construction

A. shorted

In the shaded-pole induction motor, the shading coil acts like a transformer with a(n) _____ secondary winding. A. shorted B. open

A. inductance

Multispeed fan motors achieve multiple speeds by inserting additional _____ in series with the run winding. A. inductance B. poles C. capacitors D. resistors