In accordance with NEC 440.22, the rating of fuse or circuit breaker for motor compressor shall not exceed 175% of nameplate FLA of motor or brach circuit selection current, whichever is greater.
1) My main question is that we usually set the rating of circuit breaker of 250% of FLA for usual induction motor but why 175% rule is applied for motor used for compressor.
2) What is branch circuit selection current?
3) Why does NEC require whichever is greater between 175% of FLA and branch selection current?
