motor ? - Correct Answer weather-protected
A three phase induction motor may have - Correct Answer 2 poles
a three phase synchronous motor has three stator windings that are - Correct Answer 120 degrees apart
A wound rotor motor has been recently put back into service but is now rota...
A motor enclosure that minimizes the entrance of a rain and airborne particles to the electrical parts is consider a ___
motor ? - Correct Answer weather-protected
A three phase induction motor may have - Correct Answer 2 poles
a three phase synchronous motor has three stator windings that are - Correct Answer 120 degrees apart
A wound rotor motor has been recently put back into service but is now rotating in the wrong direction. after
examining the motor, you find that lead L1 is connected to T2, L2, T3 to T1. to correct the rotating, you should: -
Correct Answer connect L2 to T1, L2 to T3, and L3 to T2
According to NEMA definition, which of the following is a type of open motor - Correct Answer eather-protected
According to NEMA definitions, which of the following is a type of totally enclosed motor? - Correct Answer water-
cooled
Any exposed live parts must be guarded if they are operating at - Correct Answer 50V or more between terminals
DC injection braking is used on - Correct Answer the stationary windings of AC motors
due to the absence of any moving electrical contacts, which type of motor should be used where the motor is
exposed - Correct Answer squirrel cage induction motor
For a constant-torque load, the horsepower increases and decreases - Correct Answer in direct proportion to the
speed
For a given number of poles, which of the following determines the speed of an AC motor? - Correct Answer
Frequency
horsepower is used to rate the - Correct Answer output capacity of a motor
How many motor designs does NEMA designate - Correct Answer 5
In a DC series motor, how much of its full-load torque is developed at starting? - Correct Answer 500%
In a split-phase motor, how much greater is the starting current when compared to the full-load current? - Correct
Answer 6 to 8 times
NEC article 430 covers - Correct Answer the application and installation of motors
slip is best described as . . . - Correct Answer The difference between the synchronous speed and the speed of the
rotor in an induction motor
The capacitor-start motor is the single-phase motor type that has the - Correct Answer highest starting torque
The most common service factor appearing on a motor's nameplate is - Correct Answer 1.15
The NEC requires motor disconnecting means be - Correct Answer within sight of the controller location
the primary method of varying the speed on a dc shunt motor is to adjust the voltage and current on the field winding
or the - Correct Answer armature
The Speed of a three-phase squirrel cage induction motor is controlled by the frequency of the applied voltage and -
Correct Answer the number of poles
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