440.22(A) Application and Selection
(A) Rating Or Setting For Individual Motor-Compressor
(A) The motor-compressor branch-circuit short-circuit and ground-fault protective device shall be capable of carrying the starting current of the motor. A protective device having a rating or setting not exceeding 175 percent of the motor-compressor rated-load current or branch-circuit selection current, which-ever is greater. shall be permitted.
Exception No.1: If the values for branch-circuit short-circuit and ground-fault protection in accordance with 440.22(A) do not correspond to the standard sizes or ratings of fuses, non adjustable circuit breakers, thermal protective devices, or available setting that does not exceed the next higher standard ampere rating shall be permitted.
Exception No.2: If the values for branch-circuit short-circuit and ground fault protection in accordance with 440.22(A) or the rating modified by exception No.1 is not sufficient for the starting current of the motor, the rating or setting shall be permitted to be increased but shall not exceed 225 percent of the motor rated-load current or branch circuit selection current, which ever is greater.
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