480 volt to 400 volt transformer

[Electric-Light]

I guess I didn't explain that very well - Its a 500 KVA machine. It needs both the 480V and the 400 volt supplies. It's not one or the other. So the manufacturer already knows it will be installed where only 480V is standard, and they have decided some of the power can be supplied directly at 480 volts, and some has to be 400 volts. They have also stated that 60 hz is fine for both supplies.

even then, that transformer should work.

 

[iceworm]

Does anyone make a transformer with a 400 volt secondary? Or can I get a custom wound transformer to provide this voltage? ....

How about 416V? ... A -2.5% tap will take the output down to 406V ...

They ask for a 2% tolerance, and the utility is normally off by a little, so I don't think that quite gets me there. ... .

Following others comments: Using precise engineering definitions - You're screwed.

I've never seen a utility guaranteeing 2%. And, I doubt the full load - no load regulation on a normal transformer will even meet 2%. You can likely order a special design xfm that will get the regulation to less than 2% - the mfg will sell you a 750VFA with a 300KVA nameplate. Of course the inrush will be a killer - and that doesn't fix the utility normal +-5%

I'll be curious to the customers reaction when you give them the price for a system that will hold 2% come hell high water, or hurricane, and hold up to the utility normal fluctuations

I'm guessing they won't be quite so stuck on 2%. Then again, maybe it is a piece of medical lab equipment and the response is, "Yep - that's what we figured."

good luck

ice

 

[kingpb]

Following others comments: Using precise engineering definitions - You're screwed.

I use that daily!!! :lol:

 

[Besoeker]

They have also stated that 60 hz is fine for both supplies.

Have you had that in writing?

 

[just the cowboy]

I use a half dozen

I use a half dozen

I have a few in my plant but they are 460 to 380 v. (I just trashed one for aluminum.) They all came with the machines so check with the machine supplier they can probably get what you need.

 

[mbrooke]

That's a great idea. What size transformers would you use?

Never mind :ashamed1: You posted the idea first.

As for 415 volts over 400, IMO it should not be an issue.

 

[steve66]

I found out Square D can make a custom transformer with a 400V secondary. And it doesn't look like the price is going to be that much different than a regular 300KVA transformer.

 

[GoldDigger]

I found out Square D can make a custom transformer with a 400V secondary. And it doesn't look like the price is going to be that much different than a regular 300KVA transformer.

As long as the lead time fits your schedule....

 

[steve66]

As long as the lead time fits your schedule....

It doesn't sound like the lead time is going to be any longer than it is for any of the other electrical equipment.

 

[mbrooke]

I found out Square D can make a custom transformer with a 400V secondary. And it doesn't look like the price is going to be that much different than a regular 300KVA transformer.

MGM transformer is another that will custom make an kind.



http://www.mgmtransformer.com/