Thanks for the follow up guys. Yep, I know the breaker protects the circuit. I was pretty sure you should base motor circuits so that a continuos load does not exceed 80% of the circuit rating. So I'm good there at 21A.

Next question I have is since I've scrapped the idea of multiple circuits off a 3 phase load center because I really don't need it...I would run only one machine at a time...and 3 phase breakers are $$$$$...I am installing a 240V 30A three pole fused disconnect off my RPC because I want to protect the circuit and the RPC should not be started under load. It's easier to throw the disconnect to off than it is to run around to all the machines. The Fusable Disconnect I purchased is a Square D Model D-321-N. IKt says max HP is 7.5 but requires the proper time delay fuse...okay, what's that? I mean I assume this handle the greater than 30A the motor would pull momentarily at start-up, right?