New Transformer Calcs

[laketime]

I am working on a project and things just went from no problem to "what???"...so I need some help. We are going to be feeding the building with 3 phase 480v to feed some new equipment. I am filling out a load sheet for the utility company and I need some 208v 3 phase loads included in this 480v service. I need to size a transformer that has a 480v primary and a 120/208v secondary. The 120/208v secondary will feed 4 machines with a start up of 150 amps at 3 phase 208. In addition they want some peripheral equipment fed with the machine. We are looking at 200amp 120v/208v feed per machine location. What would transformer size need to be?

 

[jumper]

Without knowing all the specifics of the other equipment and whether all 4 machines run at the same time:

A quick ballpark guess would be a 225 kVA transformer.

 

[laketime]

The machines will be running concurrently. The peripheral equipment would be something small like a 120v 20 amp shrink wrap machine.

 

[jumper]

I just noticed you said "start up". What is the actual FLC of these machines?

 

[kingpb]

I just noticed you said "start up". What is the actual FLC of these machines?

I'd still go with your original assessment of 225KVA.

 

[ActionDave]

If that is true I would sure hope that there is a way to run the equipment on 480V.