Don't know if I fully understand 430-53 or not. I have several pieces of machinery to wire. One particular piece of machinery has 2 motors. One motor is 30 HP, and the other motor is just 3/4 HP. I was sizing the OCD by adding the FLA amperage of both motors, then multiplying that by the appropriate column of Table 430-152, which in this case is 250%. Article 430-53b says that the branch circuit short circuit device is not to exceed that allowed by Section 430-52 for the smallest rated motor etc.... Is this just saying that each motor has to have it's individual overload protection ( heaters ) or is it saying that the breaker supplying these cannot be figured as I stated above? sorta confused. Thanks again.... I gotta get this stuff right, pretty involved motor job I got going here.
