Transformer help

[oz111]

Hello guys

I have a 3-phase, 250kVa transformer at my site.

Specs on its label are:

250kVa
cooling type: ONAN
freq: 50hz
rated voltage: 20.000/400


My question is:

How many 1phase , 220v , 3500 watt cryptocurrency servers can i run simultaneously without damaging the transformer ?

*In on other words, how many amps can each phase withstand , by approaching the limit but without damaging the transformer ?*

 

[therealdippy]

Based on that data, none. The secondary is 400V so very likely above the maximum rating of the server PSU.
kVA refers to how many 1000 volt amps the transformer coils can carry in total assuming 100% efficiency.
To work out how many servers you'll need to calculate the power factor. For example if it is 0.8 then 57 servers is possible.
Of course that assumes that the 20kV supply is sufficient. Transformers also have temperature dependent load losses.