All - I found this installation the other day while in an area I am not officially in charge of. I called the person in charge and recommended he have it removed form service that day before something bad happened. Obviously that didn't happen. If your electrician installed this would he still be working for you? How about his supervisor who did not have it removed? The other option would be I'm the crazy one and it's no big deal. After all it's a welding plug.........................

I've seen that a thousand times. Well, that's an exaggeration but a hundred times at least. Very common to install welding plugs on panels like that especially in mechanical rooms during construction so the plumbers and fitters can weld pipe joints on weld pipe jobs. Iron workers and millwrights often use electric (as opposed to gas powered generator/welders) welders too. The receps often just get left behind.

If they are protected with a breaker and right size wire I don't see it as a big deal.

I work at a Div. 1 university with about 100 buildings, 50 of which are "major" buildings and probably all of those "major" buildings have at least one of those setups. If the contractors didn't leave some behind then our guys added them later over the years as they needed to fabricate something on-site.

It just occurred to me that what you may be referring to with your smiley face was that the panel was receiving power through this plug and it is not a welding plug through the use of a so-called "suicide cord".

Is that the case?

Either that or the recep is not a 480V recep. Can't really see it clearly enough to tell.

Sorry for my picture skills and vagueness. My concern is the 250v device on the 600v system.

250V device on a 480V system? Looks like a 6-50 re-labeled for 480. Not good.

Well it is both an NEC and an OSHA violation. You could report it to the local AHJ or OSHA office. Better that than being called to testify at a lawsuit after someone has been injured or worse.

That definitely is a listing violation if it is (and it looks like it from the photo) a 6-50R device.