A convection oven with nameplateinfo: 11kw, 208 3ph or 240 1 ph.

It has three wire leads, blk, red and white coming from the oven.

Is the 3 phase connection red to line 1, blk to line 2 and white to neutral? Can someone clarify.

What does the wiring diagram show? Have you read the instructions?

A white wire? How about using a meter to see what's really coming to the oven?

It certainly sounds like this is single phase equipment and they are just recognizing that if you are on 2 phases of a 3 phase wye it will see 208v.

That 3 for 3-phase must be a typo! For just an 11KW oven, it's probably your choice of 208V 1-Ph or 240V 1-Ph. But I wouldn't guess; if no manual or diagram is available, can you call the manufacturer of the oven for clarity?

Any chance this is a Hobart commercial convection oven?

If so they can be configured for either supply system.

You need to look at the wiring diagram and compare it to the connections in the oven to determine if is presently wired for single or three phase.

Some commercial ranges like the Garland ones say single or three phase on the talley plate. They give you all the different ways they wire their stoves depending on what you order. Basically one talley plate for every stove. You have to specify how you want it wired so it is compatible with your supply.
In your case it seems to be wired 3 wire 240 or 208V because of the neutral.

Does he have a neutral or just a white wire in the cord?

Bob

I guess I assume too much and would normally think that he knows where the leads are going before he connects them up.

MY BAD

If it has a cord see where the wires are going. Make sure the cord has a bond. By following the white lead you determine that it is a neutral hook the white wire to the identified conductor. You would figure there would be a diagram on the stove for you.

If you are unsure about these connections find more info on the range, get in contact with a distributor, don't rely on forums for this info, you don't want to do any costly mistakes.

Rob

There's a good chance that some internal connections need to be changed for differing systems. RTFM!

Yes it is a Hobart Convection Oven. Now that you say that, it would make sense that some internal connections need to be changed for the 2 different systems. It is the only thing that makes sense.