Electrical Control Circuit Quiz

In a motor control circuit with multiple start/start pushbutton stations, the stop buttons would be connected in ______ and the start buttons would be connected in _______.

• Series, parallel

• Parallel, Series

• Series, Series

• Parallel, Parallel

If the circuit in the drawing was operating normally and an overload occurred, then

• Both lights would come on

• The green light would come on, and the red light would go out.

• Both lights would go out

• The red light would come on, and the green light would go out.

The essential difference between a magnetic motor starter and a magnetic contactor is that the contactor does not contain:

• Shading coils

• Holding contacts

• Overload relay protection

• Horsepower-rated contacts

The rotation of an AC three-phase induction motor may be reversed by interchanging:

• The control circuit.

• The forward/reverse interlocks

• The forward reverse coils.

• Any two power lines

Overcurrent protection can be achieved by:

• A

• B

• C

• D

Overload protection can be achieved by:

• A

• B

• C

• D

If an AC magnetic contactor with a 480V coil was energized with 120V, then most likely the:

• Overload relay would trip.

• Contactor would not pick up.

• Control circuit fuses would blow.

• Coil would overheat during normal operation.

When energized by the control circuit, start or stop a control action

• A

• B

• C

• D

In a ladder diagram, a dotted line between two coils generally means that the two coils:

• Are operated together.

• Are mechanically interlocked.

• Are electrically interlocked.

• Have a common set of contacts.

The _________ PB switch must be connected in parallel with a set of _________ auxiliary contacts on the motor starter to hold the state.

• NO Start, NC

• NO Start, NO

• NC Start, NO

• NC Start, NC