ECN Forum Forums Code Related Discussion NEC & other Code issues 3 pole single throw

Down the line I was asking about multi wire circuits and dandy answered he saw a 3 pole breaker for a 110 circuit ,first would not that be a code violation as you are not allowed to use 3 phase items in a single ohase situation or did I miss something but in his post that is only one of the several violations I noticed correct me if I'm wrong

Doc,

Just yesterday I started a job that has a multiwire circuit on a 3 pole breaker. The key is that it is in a 3 phase panel. I just scaned through the Code an did not find anything about 3 phase breakers in single phase panels but it makes sense it is something you would not do. The multiwire circuit I am installing is to be used for 6 soda machines grouped togeather w/two machines on each circuit. It's in a school and if one machine trips the breaker all six machines will shut off. Because no harm will be done if that happens I decided to put the multiwire circuit on a 3 pole breaker. I also do not have any control over who may mess with this circuit after I am done so a 3 pole breaker was the safest way to go.

Dave T.

Look at 384-16(f). A three pole breaker can only be installed in panels with 3 phase buses.
Don(resqcapt19)

Don;
In regards to 384-16, quite some time ago I came upon a rather interesting arrangement of a 3 ph breaker in a single phase panel, and was told it was a "delta" deal....which apparently was the practice before 384-16-F, maybe G. I think someone was sneaking a phase into that panel, but I'm not sure, as we demo'ed the whole deal before I could investigate. I'm still not sure just what a "delta" breaker is.....

A couple of years ago I came across an "environmental chamber" for a circuit board production facility. It had 3 seperate cords plugged into 3 seperate receps, which were connected to heating elements inside the cabinet. We replaced this setup with one 4 wire circuit, which was connected to a 3 pole breaker(one source of supply). None of the interior connections were changed, so nothing was operating at more than 120 volts. Is this what you meant?

Sparky,
I think that a delta breaker was used in the past when there was only one or 2 three phase loads. It connected to the 2 buses in the single phase panel and had a connection for the third hot that was not connected to the buses. You then fed your 3 phase load from the load side of this breaker. I've never seen one and may be wrong about what it does, but somewhere in the distant past I seam to recall reading about them.
Don(resqcapt19)

I can understand a 3 pole in a 3 phase system running single phase equipment and I can understand using multiwires when you have to what I don't understand is why a person would use the 3 pole in a single phase panel and leave it and if you are running a circuit any way what is wrong with spending a couple of bucks more for a little extra wire.If you tell the person you are doing the work for that code is the least that can be done but for a couple of more dollars not only is it a little safer it is more than the code requires.I realize that we have no control over someone latter getting into a circuit but what is wrong with trying to push a little more safer and better way of doing something.I bet you don't leave bald worn out tires on your wifes car or if you do you warn her about the bad tire before she drives off so why not be a little bit safer when doing work ,not picking at you this is a general question to everyone.
I think we do have a responsibility to worry about someone latter getting into something we have done.

Doc,
I don't see any safety issue in using a 3 pole breaker in a single phase panel to feed 3 single phase loads. There is a continuity of power issue in that if any pole is overloaded all 3 poles trip, but not safety issue. Yes, it is a code violation, but what safety problem is created by its use?
Don(resqcapt19)