I am trying to size the short circuit protection for a combination load. Normally I would use table 430.250 and use between 120 and 250% of the largest motor plus the sum of all the other loads. I have a data sheet for a 40 Hp 900 RPM motor which indicates that the FLA for the motor is 63. Table 430.250 indicates that 52 amps should be used for a 40 Hp motor. This won't work if the known FLA is higher than the numbers in the table. I am unsure of how to correct the table for different synchronous RPMs, or if I should use the data sheet I have for the motor. Normally, the values in the table are higher than the FLA of motors I typically encounter. What should I do?
