Load of three two-phases resistances 1

[giuseppe]

Hi to all.

I have a question that maybe simple for some of you guys.

I have to supply a transformer with a cable (primary) sized for three loads (secondary) of 150KVA two-phases resistances @ 400Vac phase-to-phase.

What will be the resulting, effective load on the Primary, as to size the primary cable? From my prespective, as i will load the phases with balanced two-wires phase-to-phase load, it should be approx 2/3th of the resulting 450KVA, but I am unsure, as it's not usual for me to supply two-phases loads.

Thanks for your replies.

Giuseppe

 

[jghrist]

450 kVA. The tricky part is if you don't have three balanced Ø-Ø loads, but only one or two. In this case, Google "Omaha Fudge Factor".

 

[giuseppe]

Thanks jghrist.

I didn't found the Omaha part of it (only "sweet fudge"...), but the "fudge factor" is well known.

I will go for the 450KVA, then.

Best regards.

Giuseppe