Single-Phase Motors
On a capacitor-start/capacitor-run motor (that has 2 capacitors) The start capacitor will be ___________ the size of the run capacitor.
10-15 times larger
Because of the start of the start capacitor, capacitor start motors should be limited to no more than ___________ starts per hour
8
The ideal phase angle difference between the start and run windings on a capacitor start induction run motor is
90 degrees
A 2 phase power system has two voltages which are.......
90 degrees out of phase
If a split-phase motor only hums rather than turns at start-up, the likely cause is __________
A faulty centrifugal switch
Although the universal motor has a wound armature and brushes like a DC motor. it has an added component which is
Compensating winding
Which would be used to disconnect the starting circuit of a split phase motor?
Hot wire relay, centrifugal switch and current relay
Single phase synchronous motors are based on the stator of the shaded pole motor. They operate at a speed which is synchronous with the applied frequency. These motors are also called
Hysteresis
In a purely capacitive circuit, the current __________ the applied voltage by ______________
Leads, 90 degrees
If a motor has a dual voltage rating how would the two windings be connected to operate on the lower of the two supply voltages
Parallell
Coils are made of wire that has both inductive reactance and resistance. The more pure the coil, the more inductive reactance and the less resistance it will have. The ratio of inductive reactance to resistance is what determines the __________ as compared to the applied voltage.
Phase angle
Which type of single phase AC motor has each pole physically divided into 2 sections with the smaller section wrapped in a shorted coil?
Shaded pole
The conductor size for a multi-winding motor shall be based on ____________
The configuration with the highest FLA 28-804
The direction of rotation of a split-phase motor is determined by viewing
The rear or opposite drive end of the motor
The ___________ motor can operate on either AC or DC voltage
Universal
Multispeed fan motors achieve multiple speeds by inserting additional _______ in series with the run winding
Windings
Which type of split-phase motor will have a capacitor in the circuit at all times even when the motor is up to speed?
Capacitor-start capacitor-run
In single-phase motors such as the resistance-start induction-run motor, the start winding can be disconnected by what?
Centrifigal switch
Where a multi-winding motor is connected in a permanent configuration it shall be treated as a _________ winding motor
SIngle
In the shaded pole motor, the shading coil acts like a(n) __________ transformer secondary
Shorted
The capacitor-start capacitor-run motor typically _____________ as compared to a RSIR motor
has a higher starting torque and a better PF
The R-90 copper conductor used to supply a 115V / 1HP / 1ph. motor would have a minimum size of _____________ (term temps are unmarked)
#12 Table 45 - 16A x 1.25(conductor) = 20A 4-006A-Temp Limitations says 60 degrees for equipment rated not more than 100A Table 2 - #12AWG
The minimum size RW90 copper conductor (terms are marked for 75 degrees) used to feed a 5HP 1ph 208V AC cont. duty motor would be ___________
#8 Table 45 - 208V means increase the 28 by 10% so 28x1.10 = 30.8x125% (for conductors) = 38.5 Table 2 says #8
The warren motor is a variation on the shaded pole motor. It operates at _____________ RPM
3600rpm
The maximum overload setting for a 5HP 200 volt single phase motor with a S.F of 1.15 would be _________ amps
40.25 Table 45 - 28 x 1.15 = 32.2 and because the SF is 1.15 you take it at 125% so 32.2x1.25 = 40.25
A split phase motor can have its rotation reversed by switching which leads?
5 & 8
The centrifugal switch on a split-phase motor is ___________ during initial start up
Closed
The output shaft of a stepping motor
Moves through a specific angle for each input pulse
A shaded pole induction motor is considered to be a ___________
Non-reversible motor
Because one set of motor leads are more easily accessible the direction of rotation of a split phase induction motor is normally changed by
Reversing the leads to the start windings
Split phase motors are so named because they operate on a single-phase voltage, but internally they divide the voltage and current paths in such a manner as to create a _____________ magnetic field
Rotating
The ______ winding is made of many turns of small wire and is located at the top of the stator core.
Start
The centrifugal switch controls current flow to the _________ windings
Start
By comparing the vectors for the start and run windings of a split phase motor we can tell alot about the ________ of the motor
Starting torque
In the shaded pole induction motor, the direction of rotation of the magnetic field is
toward the shading coil
In a motor that has a rotating magnetic field, the speed of that magnetic field is referred to as the
Synchronous speed