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FAQ03062 of Measuring / Motor Protective Relays FAQ

FAQ No. FAQ03062

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What does instantaneous operation mean for Motor Protective Relays?


Instantaneous operation refers to Relays operating the instant that an overcurrent is detected. A starting current flows in motors, so Relays do not operate for a certain time during startup and then switches to instantaneous relays operation. This is referred to as instantaneous operation with a startup lock.

K2CM Motor Protective Relay Example

Overload Operating Time Characteristics for Instantaneous Type

When it is clear that a level of current exceeding the rated current will cause an error in the load, Power Supplies must be shut down immediately. Instantaneous operation is suitable for this kind of application.

Applicable models: K2CM, SE Motor Protective Relay

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