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If I use a circuit breaker with a 1200 amp frame with a 400 amp trip sensor, will I need to comply with NEC 240.87?

The NEC 240.87 requirements apply to breakers where the “trip setting” can be 1200A or more.  The maximum trip setting of SqD breakers is based on the rating of the Sensor Plug, which can be less than the Frame Rating.  If a 1200A breaker has a 400A Sensor Plug installed, NEC 240.87 requirements do not apply.  If a 1200A Frame/1200A sensor breaker has a Long Time setting of 800A, NEC 240.87 does apply because the breaker could be adjusted to 1200A.  
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