3 Phase Motors And Starters

Front 1

An autotransformer is a component of a static phase converter that enables adjustment of the voltages on the generated line?

Back 1

True

Front 2

What is an advantage of three phase motors compared to single phase

Back 2

They are more efficient for the same horsepower rating

Front 3

How many leads are generally found in the termination box of a 3 phase 208V motor that is only started with a full voltage across the line starter

Back 3

3 leads

Front 4

In an electronic soft starter, current limit mode

Back 4

Limits the starting current to a maximum value

Front 5

The autotransformer starter reduces the starting current twice, once because of reduced voltage and again because of transformer action?

Back 5

True

Front 6

When using an autotransformer reduced voltage starter, the starting torque of the motor decreases in direct proportion to the reduction in starting voltage?

Back 6

False

Front 7

Which 3 leads of a 12 lead motor are not present in the termination box on a nine lead motor

Back 7

T10,T11,T12

Front 8

A nine lead wye connected SCIM can be used with wye/delta starter

Back 8

False

Front 9

The wye/delta starter reduces starting voltage to 57.7% of its full voltage value, the starting torque to 33%, and the starting current to 33%?

Back 9

True

Front 10

If the load exceeds the rated output of a rotary phase converter, the “manufactured” voltages will

Back 10

Decrease

Front 11

What is the maximum angle that a static phase converter can shift the generated phase from incoming single phase power supply

Back 11

90 degrees

Front 12

Phase converters are used to supply single phase motors?

Back 12

False