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What are the rules for choosing an inverse-time circuit breaker for motor circuits?<br />

The NEC permits an inverse-time CB to be sized 250% of the motor FLA. If that will not start the motor, the size may be increased to 400% for FLA 100A or less, and to 300% for FLA greater than 100A. See NEC Table 430-152 and section 430-52.


CTA-ID : 1526
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