Practice Test Geeks(PC) Professional Electrical Contractor Practice Test
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Motors and Motor Controls Flashcards

6 cards from real PC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 6 Motors and Motor Controls flashcards as text

  1. What is the minimum horsepower rating required for a motor disconnecting means per NEC 430.110?

    Answer: Equal to the motor's HP rating

    NEC 430.110(A) requires the motor disconnect to have an HP rating at least equal to the motor's HP rating at the applied voltage.

  2. Per NEC 430.102, where must the motor disconnecting means be located?

    Answer: Within sight of the motor and within 50 feet

    NEC 430.102(B) requires the motor disconnect to be within sight of the motor, meaning visible and not more than 50 feet away.

  3. What type of motor starting method is used to reduce inrush current during startup?

    Answer: Reduced voltage starting

    Reduced voltage starters (autotransformer, wye-delta, or electronic soft starters) limit inrush current by applying less than full voltage during starting.

  4. What is the standard secondary voltage for a motor control circuit transformer per NEC 430.72?

    Answer: 120V

    NEC 430.72 permits control circuit conductors supplied by a grounded transformer secondary at up to 120V without additional overcurrent protection in many cases.

  5. A squirrel cage induction motor is classified as what type of motor?

    Answer: AC induction motor

    A squirrel cage induction motor is the most common AC induction motor, named for its rotor conductor arrangement that resembles a squirrel cage.

  6. What does NEMA MG1 classify regarding motor construction?

    Answer: Motor enclosure types such as ODP and TEFC

    NEMA MG1 is the standard that classifies motor enclosure types including Open Drip Proof (ODP) and Totally Enclosed Fan Cooled (TEFC) among others.