Quote Originally Posted by Mike Cutler View Post
There are two things that need protection on a motor circuit. Whether there is a single motor, or multiple motors.
The motor(s) needs to be protected. This is accomplished by determining the correct size wiring to carry the current.
The wires, or conductors, or branch circuit need to be protected. These are protected by selecting the correct breaker size.
The particular section of the NEC that deals with motors is Article 430. At the beginning of article 430 there is a flow diagram that breaks down the article into the parts and the sections of the code that apply to each part, and the reference to the correct article, not contained in 430, that apply.

NEC 430.24 addresses multiple motors and branch circuit sizing requirements;
125% of the FLC of the largest motor plus the sum of FLC of the other motors . to determine branch circuit sizing and breaker protection.
My copy of the 2005 code is at work, so I'm kinda running off memory right now. Dangerous,I know.
If someone has an NEC copy, perhaps they can work through Article 430 to answer the question more completely.
Mike,

I generally agree with what you posted, but there is another factor with motors - overload protection for the motors. To run multiple motors on the same circuit, one would need to ensure that the individual motors have appropriate overload protection. The circuit breaker protecting the wiring could well be too large to protect the motor. In that case, a separate overload is required to protect individual motors.

Rob