Is there such thing as a 240V branch circuit?

[Tom Jones III]

Whenever a thread gets started about 240V service it often boils down to mysterious sections of the NEC that clearly state that every 240V motor must be on a separate circuit, but these people don't say where in the NEC this is stated. Other people say this only applies for "large" motors or industrial applications without citing chapter and verse and without explaining what large or industrial means.

I would love to have concrete answers (not opinions - I get those from my MIL) to the following questions but I don't know how to get the answers short of asking an inspector to come out which sounds like inviting the fox into the hen house.

* If every 240V tool must be on it's own circuit, then does a 240V 60 watt light need to be on it's own circuit? How about a 1 HP 240V hand held router? What if this 1 HP router is table mounted? What is the criteria for requiring it's own circuit?

* If each 240V tool does not require it's own circuit then do 240V circuits follow the same rules as normal household branch circuits?

* How do I connect my 240V tools that are in the middle of my shop to overhead power and stay within code?

* Do monkeys sweat like humans or are they like dogs and for all practical purposes do not sweat?

[Don Baer]

Tom,
Actually every circuit you have in you house other the incomming MAIN is a branch circuit. Back in the day when I used to build panel for motor control this is how we did it. First of all the main circuit must be sized so that the main breaker feeding a circuit can withstand 100% of all loads plus 150% of the biggest load. The conductors in the main circuit must be sised the same lets say you are feeding 3 circuits 1 @ 10 amps, 1 @ 15 amps and the 3rd at 20 amps so the main breaker and feeder conductors must be able to carry 55 amps (10+15+30)amps. Now I don't have the code book in front of me so I can't site section of the code where it states this but I have never had a panel fail inspection.

I hope this helps.

[Russ Filtz]

In my garage shop I had an overhead 240V circuit running along the ceiling running to a locking receptacle. Inspector didn't even blink at it. Is this supposed to be against Code or soemthing?

[Tom Jones III]

What is the proper terminology then for the standard circuit inside a house that will have several general purpose receptacles? There are sizing rules for these circuits governing the size of the romex, the number of receptacles and the circuit breaker size. I have always wondered why can't 240V circuits follow similar rules?

Overhead power - my consumer checklist verion of the NEC called "Code Check" says that NEC requires "strain relief". I have been told, I think on this forum, that all that means is that the cable be securely fastened to the box that houses the receptacle. I think that is what they are calling the clamp that holds the romex when it enters a junction box or receptacle box.

[Cecil Arnold]

Tom, you are more or less correct on strain relief. It is meant to prevent the bare wire, where it is connected to (whatever, lamp, plug, motor) from being pulled from the connector and creating a shock hazard.

[Rick Christopherson]

It is NOT true that every 240 volt tool needs its own circuit. This is the myth that keeps causing all of the problems and confusion. You won't find an NEC reference to this because the NEC doesn't distinguish 120 from 240. (That's the myth).

Yes, 240 volt branch circuits follow the same rules as 120 volt circuits. There is no distinction.

This next item I do not know for certain, but to the best of my knowledge, a cable-clamp does not constitute strain relief for an overhead pendant. I do know that there is a section in the code for pendants, but I'm not going to go hunting for it to lookup the details.