Protection Engineering Basics and Schemes Protection Engineering | Página 269

9.3.1 Low Voltage rating motors up to 100KW
The controller of this type of motor shall have below
mention protection
 Overload
 Short circuit
We prefer Miniature circuit breaker for this rating of
motor
9.3.2 Low Voltage rating motors beyond 100KW
The controller of this type of motor shall have below
mention protection
 Overload
 Short Circuit
 Locked Rotor
We prefer Air circuit breaker for this rating of motor
9.3.3 High Voltage rating motors
The controller of this type of motor shall have below
mention protection function in relays
 Thermal Overload with trip and alarm provision
 Short circuit
 Unbalanced
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