1. The direction of rotation of three-phase motors can be reversed by interchanging any two-motor leads to the line.
a. True
b. False
2. Push-button interlocking is an electrical method of preventing both starter coils from being de-energized
simultaneously.
a. True
b. False
3. NEMA specifications call for a starter to be derated.
a. True
b. False
4. Electrical interlocks are usually mounted on the side of a motor starter.
a. True
b. False
5. To reverse the direction of rotation of single-phase motors, both the starting and running winding motor leads are
interchanged.
a. True
b. False
Name: Class: Date:
Unit 21 Interlocking Methods for Reversing Control
6. If magnetic control devices are to be used, then reversing ____ accomplish the reversal of the motor direction.
a. transformers b. transducers
c. rotators d. starters
7. A mechanical interlocking device is assembled at the factory ____ the forward and reverse contactors.
a. on top of b. below
c. between d. adjacent to
8. Reversing starters are available in ____ construction.
a. horizontal and vertical b. parallel and series
c. mechanical d. power-coil
9. Reversing starters consisting of mechanical and electrical interlocked devices are preferred for ____.
a. easier maintenance b. maximum safety
c. easier operation d. economic reasons
10. The term interlocking is used generally when referring to motor controllers and control stations that are ____ to
provide control of production operations.
a. fixated b. interconnected
c. connected d. programmed
Name: Class: Date:
Unit 21 Interlocking Methods for Reversing Control