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I have worked on machinery from Europe that has 2-wire grounded 240V in the panel. This is just like the 2-wire grounded 120V we use in the U.S. In other words, you have 2 wires coming off the secondary side of a single phase transformer at a potential of 240 V. One leg is grounded, giving you a neutral. This has the benefit of simplifying wiring, as well as saving money since relays, contactors and circuit, breakers only need to be single pole to kill circuits, rather than double pole.

My question is: Is this legal in America?

There is obviously nothing wrong or unsafe in doing this. The only problem I can see, is that it isn't standard here in America.
 

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Yes, it is legal. But the machine doesn't care if one leg is grounded or not. It will work fine on standard 240 V with two hots, assuming it is compatible with 60 Hz.

If you had a single phase transformer that was tapped at 240 V secondary, it would be perfectly legal to ground one leg.
 

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Do you know of an NEC article stating this (in case someone asks for proof)?
As far as I know, the NEC does not dictate voltages, only standard nominal voltage values and maximum voltages applied to certain systems. 250.26 states what wire is to be grounded in a system. 240 V is a standard value, and I don't know of any place in the Code that says it must come from two hots instead of a hot and grounded conductor. In fact, 240 V corner grounded delta systems have 240 V to ground on two phases.

Maybe someone else will come along with a more definitive Code reference.
 

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I would ask the inspection dept. on that one.. Special Inspections can get nasty.
Also check the fusing with-in they tend to reject fusing not approved in North America.
 

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I would ask the inspection dept. on that one.. Special Inspections can get nasty.
Also check the fusing with-in they tend to reject fusing not approved in North America.
That typical true and what more the conductor colour is not the same as well depending on where you get the machine from.

There used to be about pretty close to a dozen diffrent colour codes but now it whittle down to at least 2 I know for sure.

Now speaking of fuses they have diffrent AIC rating than North America requirement and some case it will not approve in North America area so that something you have to watch out.

I don't useally have issue with European fuse at all { I am used to it and it can get nutty if not pay attetion to it}

Merci,Marc
 
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