Um...... maybe I'm wrong......

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480sparky

480sparky

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.......... but...............

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... don't you need NEMA 3ph receps for 3-phase circuits?



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What about a 3?, 3w corner grounded Delta? OK, I admit that just a far fetched guess. :)
 
Even with a 208/120 transformer supplying the panel if the neutral is not required then there is no reason it has to be at the receptical, but if those receptacles are fed with all three phase conductors and the EGC, it is still a listing violation and a 406.3(F) violation because the bottom terminal is marked as a neutral connection and a single phase load could be wrongly plugged in which would fry it because of line voltage on the neutral terminal, I seen many welders have these installed for them, but most are single phase welders.
 
hurk27 said:
Even with a 208/120 transformer supplying the panel if the neutral is not required then there is no reason it has to be at the receptical, but if those receptacles are fed with all three phase conductors and the EGC, it is still a listing violation and a 406.3(F) violation because the bottom terminal is marked as a neutral connection and a single phase load could be wrongly plugged in which would fry it because of line voltage on the neutral terminal, I seen many welders have these installed for them, but most are single phase welders.
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Well, considering this is a rotary phase converter to run 3ph equipment on 1ph power, I'd say the receps are wired for 3ph.
 
480sparky said:
Well, considering this is a rotary phase converter to run 3ph equipment on 1ph power, I'd say the receps are wired for 3ph.
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I agree with you that this is a clear violation of 406.3(F), I'm curious as to what this set up is for? they took the time to make it a nice looking installation even down to the nice varnished wood everything seems bolted to, at first I was thinking welders and is why I mentioned it, but that wood would not last very long around welders or welding, also I know what the proper NEMA 50 amp rated 3-phase receptacles would have cost which was most likely why they went this route, but the only problems I see other then the 406.3(F) violation are the fact that these range/power receptacles will most likely not last long as they are easily breakable and are not really designed for repeatedly plugging in and out loads as they are not a very durable receptacle, and the fact if someone ever plugs in a single phase load that uses a neutral then what ever loads on what should be the neutral is toast.

Do you know what this set up is for?
 
I agree it is not right.

Will also say I have seen same receptacle used for three phase many times - usually on farms, and usually for portable augers for loading/unloading grain storage bins.

Risk of plugging in something with a neutral was not really that great in each instance. Not too likely someone will be bringing their range out to the grain storage bin and wanting to plug it in there - unless maybe they were going to cook up some homemade whiskey from the corn stored in the bin??:)
 
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