feeder size for transformer

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Dlectric

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I am working on a single phase 480 volt to 120/240
volt 25 kva transformer does anyone have the calculations for feeder size and overcurrent protection handy my references are not available at this time.Total load is 60 amps.
 
Re: feeder size for transformer

Do you remember ohms law?
I divide the Kv by the primary voltage and that about the size of the OCP.
Ditto on the secondary
 
Re: feeder size for transformer

Thank you for the reply. I was wondering about the fuses needing to be rated at 125% of the FLA of the secondary for 600 volt or less secondaries.What do you think?
 
Re: feeder size for transformer

Transformer KVA 25 1 Phase
Primary volts - 480 Secondary volts - 240
Pri. Amps - 52V Sec. Volts - 104V

Max. size OC Prot . Amps

Protection type,
For Pri. And Sec.
Pri. @ 250% = 150 amps
Sec. @ 125% = 150 Amps

Protection type.
For Pri. only
Pri. @ 125% = 70 Amps
Sec. not required
 
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