Segment 4 Quiz 2

thyristors

SCRs and GTOs are ___ and have the ability to handle more current

synchronous

___ motors are often made to have a leading power factor by over excitation of the rotor current

12.2

a one horsepower motor will have a full load current of ___ amperes when connected to DC

1200

a three phase motor contains six poles per phase. the synchronous speed of this motor is ___ RPM when connected to 60 Hz

brush

direct current compound motors contain a rotating armature and a ___ field

increased by 10%

if a synchronous type motor is operated at 90 percent power factor, the rated full load current in the table is to be ___

horsepower rating

in a machine that has a 3 phase motor rated at 460 volts, the current required on that machine is based on the motor ___

nine

most deal voltage motors bring out ___ "f" leads at the terminal box

split phase

most dual voltage single phase motors will be of the ___ type, which contains both run and starting windings

degrees

state the unit to measure coil span?

diode

the ___ operates like an electric check valve, it permits the current to flow through it in one direction

on the nameplate

the motor overload size is to be determined by using the current listed ___

synchronous

the speed of the rotating magnetic field of a polyphase oc motor is called ___ speed

resistance

the speed of the wound rotor induction motor can be controlled by the amount of ___ connected in the rotor circuit

in UL product directories

the temperature ratings of devices such as circuit breakers, fuses and terminals are found ___

in phase

the torque reaches maximum when the rotor and stator currents are ___ with each other

90

the voltages of the two phase system are ___ degrees out of phase of each other

delta

three phase motors can be constructed to operate in either way or ___

low speed high torque

two phase motors that are especially designed for ___ applications use the same rules for determining full load currents as single phase motors

high speed low torque

what is the general application for most motors?

156

what percentage of the full load current of a thermally protected continuous duty motor of more than one Hp can the trip current be, if the full load ampere is 15?

the square root of two

when a two phase, three wire system is used, the size of the neutral conductor must be increased by

430.248

which NEC table lists the running currents for single phase AC motors