Our Senior Electrical “Engineer” has purchased a 25KVA DYN transformer in error! OOPS!
So other than a very expensive and heavy door stop what possible use would it be?
3PH 400v input / 3PH&N 230V output.
Cost £2000+ been offered £250 for scrap!

IANAEE, but I would guess it’s used for running high current 230v stuff, such as a welder, off a 3PH supply.
Why scrap it?
Why not just sell it on, albeit at a loss, but for more than £250?

Send it back and just pay a restock fee?

Is the 230v the line to line voltage or line to neutral?

Well 400V 3ph is standard LV from the electricity network (although it’ll probably be up around 415 to 433 in practice).

230V is more interesting. If that’s ph-ph then I have no idea. If it’s ph-neutral then you’ve got a one to one delta star transformer. Could be used for reducing flicker caused by equipment like welders or for reducing phase imbalance on the supply side caused by large single phase loads.
It would also give you a local earth isolated from the electricity system, which has its uses.

It’s 230v phase to phase with a star point neutral.
The problem is our “engineer” is self-taught and thought he was ordering 230v to neutral and as the TX was custom built the supplier has only offered £250 for it.
Not really my problem but it’s the first time I’ve seen 230v 3ph and was curious as to its uses.
Thanks

Hmm there isn’t a great demand for 133V AC

What did he actually want it for? Im assuming it’s for isolation purposes as per igm’s post

Usually use a. 1:1 delta star to create a neutral for distribution – I’m not surprised that the configuration you have is bespoke!

It is currently fitted into a U.P.S. Bypass switch, from what I gather the U.P.S. Is 3ph&n input 1ph&n output but details are vague, someone is trying to cover their a*$€ big style as there is a 3 week build time for a replacement.