30kva 3phase step up transformer

[Pratch]

Pratch

Junior Member

Join DateJan 2018LocationLoves park,Il United StatesPosts1​

[h=2]30kva 3phase step up transformer[/h]

I am running power for a sasso k600 extreme Cnc saw and it comes with a 30kva 3phase step up transformer.the saw requires 400volts, the transformers primary side is 230 volts and secondary side is 400 volts. The normal running amps for saw is 80 and a max of 125.so my ? Is what size wire do I need to run to the primary side of transformer and what amp breaker. And then what size wire coming of the secondary side going to saw? I'd appreciate any help​

 

[rlundsrud]

This is a link that should help, it covers pretty much everything about transformer calcs thay pertain to your question.


http://www.mikeholt.com/mojonewsarchive/NEC-HTML/HTML/TransformerInstallation~20020516.htm

 

[kwired]

Pratch

Junior Member

Join DateJan 2018LocationLoves park,Il United StatesPosts1​

30kva 3phase step up transformer

I am running power for a sasso k600 extreme Cnc saw and it comes with a 30kva 3phase step up transformer.the saw requires 400volts, the transformers primary side is 230 volts and secondary side is 400 volts. The normal running amps for saw is 80 and a max of 125.so my ? Is what size wire do I need to run to the primary side of transformer and what amp breaker. And then what size wire coming of the secondary side going to saw? I'd appreciate any help​

If normal running amps is 80 amps @ 400 volts - your 30 kVA transformer seems undersized to me 80 x 400 x 1.732 = 55.4 kVA.

 

[Besoeker]

If normal running amps is 80 amps @ 400 volts - your 30 kVA transformer seems undersized to me 80 x 400 x 1.732 = 55.4 kVA.

I agree. Seems to me that there are two different threads running on this same topic. I responded to the other giving input and output current ratings for the 30kVa transformer. But essentially the same conclusion that you came to.

 

[Jraef]

This is the second thread, I am closing it. The points made are however very valid and I encourage you to check your requirements.

Here is the original thread for reference or further discussion. Eventually I'll merge relevant posts into it.
http://forums.mikeholt.com/showthread.php?t=188988