1. Most motors are successfully started at 90 percent of line voltage.
a. True
b. False
2. The starting transformers are inductive loads.
a. True
b. False
3. In an autotransformer-type starter the timing for the time-delay relay that controls the transfer from the reduced
voltage condition to full voltage is not adjustable.
a. True
b. False
4. De-energizing the transformers while in the running position is done to conserve electrical energy.
a. True
b. False
5. Magnetic overload relays are used on large reduced voltage starters.
a. True
b. False
Name: Class: Date:
Unit 27 Autotransformer Starters
6. Starting transformers momentarily affect the ____.
a. service factor b. auxiliary equipment
c. power factor d. motor stability
7. In an autotransformer-type starter, autotransformers supply ____of the line voltage to the motor.
a. 45% b. 55%
c. 65% d. 75%
8. Starting compensators using a five-pole starting contactor are classified as ____.
a. autotransformer starters b. open transition starters
c. secondary Resistors d. semiautomatic Starters
9. Closed transition connections are usually found on standard size ____ and larger starters.
a. 5 b. 6
c. 7 d. 8
10. Current transformers are used on large motor starters to step down the current so that a conventional overload relay
and heater ____ may be used.
a. size b. design
c. arrangement d. connection
Name: Class: Date:
Unit 27 Autotransformer Starters