What are the protections used in a HT breaker to protect
the HT motors.

Answer Posted / sivaraman

We have to use for Motor Protection Relay (SPAM 150C)

1.Short Circuit
2.Excessive Start time
3.Thermal Overload
4.Locked Rotor during running/start up
5.Unbalance/loss of Phase/single phasing
6.Earth fault
7.Loss of Load
8.Temperature supervision of motor
9.Limitation of No. of Starts/Time between starts

All above facilities are available in this relay.

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