NCCER ELECTRICAL MODULE 2 LEVEL 2
MOTORS THEORY AND APPLICATION EXAM |
FREQUENTLY TESTED QUESTIONS WITH
CORRECT ANSWERS | BRAND NEW!
The rpm of a 60Hz motor with two poles is ___. - ✔✔✔ Correct Answer
> 3,600rpm
A(n) ______ is used to provide the switching action required for
continuous DC motor rotation. - ✔✔✔ Correct Answer > commutator
In three-phase motors, the rotor most commonly used is the
_____. - ✔✔✔ Correct Answer > squirrel cage rotor
The starting torque characteristics of a wound-rotor motor are
defined by _____. - ✔✔✔ Correct Answer > rotor resistance
A three-phase synchronous motor is started with a(n) _____. -
✔✔✔ Correct Answer > amortisseur winding
, Page 2 of 11
The speed of an induction motor depends on the power supply
frequency and the ___. - ✔✔✔ Correct Answer > numbers of poles
The speed on a multiple-winding motor is normally changed by
____. - ✔✔✔ Correct Answer > switching contacts in the motor
controller
A consequent-pole motor has _____. - ✔✔✔ Correct Answer > two
speeds
The method of braking in which DC is applied to the motor
windings after AC is removed is known as ____. - ✔✔✔ Correct Answer
> injection braking
Reconnecting a running motor to act as a generator is known as
____. - ✔✔✔ Correct Answer > dynamic braking
The two primary types of motor enclosures classified by NEMA
are ____. - ✔✔✔ Correct Answer > open and totally enclosed
An open AC squirrel cage motor that makes use of form-wound
coils and an insulation system is known as a(n) _____. - ✔✔✔ Correct
Answer > sealed windings(type)