Protection Engineering Basics and Schemes Protection Engineering | Seite 268

loss of voltage protection. Loss of voltage protection
breaks the circuit when power supply to motor lost. The
overcurrent protection in this interrupter is provided by
magnetic contactor of circuit breaker or fuses.
9.2.2 E1 Medium Voltage Motor Controller
In this controller we have magnetic contactor to start
and stop the motor, this contactor have thermal over
load protection and loss of voltage protection. For
overcurrent fault protection Instantaneous Relays (50)
are provided in this interrupter.
9.2.3 E2 Medium Voltage Motor Controller
it is similar to E1 Medium Voltage Motor Controller ,
except in place of instantaneous relays we used fuses in
this interrupter for overcurrent protection.
9.3 Types of Switchgear Control
We divide control with respect to motor rating
 Low Voltage rating motors up to 100KW
 Low voltage rating motors beyond 100KW
 High voltage rating motors
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