Electrical Interview Question : Different type of Motor protection


Explain Different type of Motor protection

1.Over Current protection
2.Over Load protection
3.Other type protection

Over current protection interrupts the electrical circuit to the motor upon excessive current demand on the supply system from either short circuits or ground faults.

Overload protection is installed in the motor circuit and/or motor to protect the motor from damage from mechanical overload conditions when it is operating/running.

Other type of protections are
Low voltage protection When supply voltage goes below a preset value it isolate the motor
Phase Failure protection Interrupts the power in all phases of a three-phase circuit upon failure of any one phase.
Phase reversal protection Used where running a motor backwards (opposite direction from normal) would cause operational or safety problems.
Ground Fault ProtectionOperates when one phase of a motor shorts to ground preventing high currents from damaging the stator winding and the iron core.

Bearing Temperature Monitors & Protection
Winding Temperature Monitors & Protection Devices
Current Differential Relays (Phase Unbalance)
Vibration Monitors & Protection