208Y/120V 240V 3ph compatibility

[Fear]

I'm wiring up my shop to at least look professional.
It's not a business and there's no reason to worry that a codes inspector might pop-up, but I'm wiring off my 40hp phase converter and want to run it through a 3ph sub panel. Since I'm running the RPC off a 125a breaker, I don't figure I need a box rated any bigger, but I still plan on putting in a larger amperage box just to have the extra breaker quantity potential. I don't plan on running any more than two 3ph devises at a time, so I'm not worried about overloading it.
The question is, since I've been buying used as often as possible to try to do this on a nearly nonexistent budget, I've been looking at fuse panels and see most of them are 208Y/120V. I'm running 240V to my RPC and I've seen a bunch of stuff that seems to interchange between 208Y/120V and 220V/230V/240V.
Can I use one of these panels with 240V 3ph?
I've been looking at GE panels just because I figure staying with one brand means familiarity and interchangeability with existing components.

[lakeside53]

To be code compliant you need a panel that is listed for 240 DELTA. Sure, at home you can get away with anything... like using a 208/120 panel and not using the neutral bar etc. Take care...

[J Tiers]

The 208Y puts the neutral in the wrong place.

What you REALLY need is not a 208, and not a delta panel, but one set up for "lighting tap" 3 phase, AKA "farm 3 phase", "stinger 3 phase", etc.

That will keep the 120-0-120 neutral, and add the 3rd line, using the proper tied breakers etc.. Gives the most legitimate options.

[Fear]

The 208Y puts the neutral in the wrong place.

What you REALLY need is not a 208, and not a delta panel, but one set up for "lighting tap" 3 phase, AKA "farm 3 phase", "stinger 3 phase", etc.

That will keep the 120-0-120 neutral, and add the 3rd line, using the proper tied breakers etc.. Gives the most legitimate options.

Do I really need a neutral if I'm not running any single phase out of it? It's just a dedicated box for the few 3ph things in my little shop. The single phase stuff is coming from the two main boxes.
One box that was 208Y/120 had a option listed in the panel fine-print that said the box could be used for 240V if no neutral was attached to the neutral bar and 240V breakers were used. Does that apply to most of the 208Y/120V boxes?

[MaxHeadRoom]

How would you obtain a valid/required earth ground?
Max.

[Fear]

I'm assuming bonding the case would be the ground. It should explain proper grounding, even on a used panel, wouldn't it?

I keep looking and finding the same "optional 240v" disclaimer on several boxes saying to just not run a neutral to the neutral buss.

[J Tiers]

If you have zero need for any neutral, then it probably would not matter. In that case, the delta panel would be fine functionally.

The ground bond would already exist at the main panel, you would NOT have bonded the sub-panel anyway. The equipment grounding conductor (green wire) would supply the safety grounding in the manufactured 3 phase wiring.

But a 208 panel would not be appropriate, although it would work. You would not use the neutral, but the panel would "imply" that it was available. That might upset an inspector. And, I am not sure what voltage to ground is labeled on the 208 panels. The actual is 120V, so it might be only a 150V class insulation.

[Fear]

You have me confused. i'm thinking most dudes running a RPC don't bother with an elaborate 3ph sub panel. I don't have to pass codes, I just want it to look professional and above all, don't want to let any smoke out of anything causing my one day, hopefully, awesome shop to burn down.
I was looking at just what a replacement front panel on one of these would cost just to have one where all the knock-outs hadn't been ripped-out and just the front panel is over $1000. That's half-way to a decent used vertical mill in my budget.
I'm wanting to have this polished and ready to go for around $300. I've seen piles of electrical boxes sent to scrap in the past. I just want to know how to pick one for my shop on the cheap.

[lakeside53]

Just keep looking until you find the right one, or....

If you do use a 208/120 Y panel, and don't want any 120v circuits, forget the neutral (but still run ground) and then any three adjacent breakers are your three phase, If they have separate handles , those breakers need to be one block (not three separate) and the handles need to be tied together.

If you do decide to use neutral for 120v circuits, you'll need to be careful NOT to use single phase breakers on your generated leg.

Around here old panels are close to free. Office building TI remodels fill dumpster with old electrical.

[J Tiers]

You CAN use the 208 panel, If the voltage to ground is rated 300V, as it probably is.

Otherwise a surplus industrial DELTA panel.

You do NOT WANT any industrial panel which is set up for corner grounding. Those will have two fuses or breakers per circuit, and will not work for you.