Pick your amperage.
NOTE: These are UL 1077 supplementary breakers which means you need another upstream breaker which can be a service panel etc. The definition of UL 1077 verse the UL 489 (no upstream requirements) is on that site.
"GFCI" is a very SPECIFIC term for a "personnel level protection" of no more than 6mA of ground current, referred to as a "Class A" Ground Fault Protective Device (GFPD). You can't find one in 3 pole because until the 2017 NEC there was no requirement for 3 phase equipment to be protected by Class A GFPD, and even now it's only for equipment that is 150V to ground or less and not hard wired, meaning 240V or 208V 3 phase. So mfrs are slow to catch up to this change and a lot of the country has not even adopted the 2017 code yet. You CAN get 3P 240V GFCI breakers, just not DIN rail mounted, they are panelboard type. I know for sure that you can get them from Square D, a QOB350GFI
Are you sure you really need "GFCI" or does someone just want "Ground Fault" protection? Because EQUIPMENT GF protection (called GFEP) is different. Lots of options there, but you won't find them using the term "GFCI" because they are not the same thing.
" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden
Yeah, it's for an special outdoor EV charging station NEMA 14-50 outlet with other metering components in the same small enclosure... Wow, that QOB350GFI unit would work, but it's crazy expensive.
You need to get a quote.
If you can get a salesman to tell you the most preferred category and then try to qualify for that category, you will get the best price.
Example:
MCC Section priced as aj addition to an existing MCC:- Quoted at $20,000
Went back.
I am sorry. this is not an addition. It is a new standalone section.
We do not have to match the existing MCC.
We need a competitive quote.
New quotation:= Just over $5000.
Don't ask for replacement parts.
Ask for a competitive quote.
You need to get a quote.
When a manufacturer will take a 300% windfall profit if you use the wrong word, to you feel morally compelled to be completely truthful?
Why are you using a three pole breaker?
The NEMA 14-50R is a 125/250 Volt device normally protected by a two pole breaker.
If you have three phase you should be using a NEMA 15-50R.
Bill
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"Why not the best?"
Jimmy Carter
Bill,
To your example, if you get a quote on 2 add-on buckets for an MCC, you will find out that the cost will be 1-1/2 to 2x as high as just ordering a single section of MCC with 3 buckets inside as a "new" project. When I do that for people and they complain about having to buy the now useless structure, I tell them that it's not useless, their buckets just came in a handy steel shipping container.
" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden
Dang, I just had to pay $250 for a 36x30x8 Hoffman to hold my solar gizmos since the plastic Target bins I tried failed after 18 months outside, literally rotting into pieces with only 2 hours of sunlight a day. Those handy metal shipping containers would work great.
Meh, MCC structures are indoor only. They wouldn't have lasted either.
Although, that said, I have a client (onion and garlic plant not too far from you, Keith) who put NEMA 1 MCCs in a wash down area. They have survived a lot longer than I thought they would have. I only know about it because they wanted me to quote on replacing just the rusted parts... I opened one of the buckets that has a VFD inside, the VFD has mushrooms growing on it! Dark, wet, warm, onion and garlic dust sucked in by the cooling fan; perfect mushroom farm.
" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden