Here is my dilemma:
My incoming voltage single phase is 255v.
I am running a rotary phase converter and my output voltage is 255v.
My Fanuc machine wants to see 208v with 233 as maximum.
I am running a 60 amp single phase input circuit with the load amps usually about 20 to 30 amps.
The Grainger calculator says I need a 2 to 3 kva buck boost with 16-32 volt secondary, BUT the Federal Pacific and Acme selection tables say a 1kva will work to go from 255 to 239 volts at up to 66.67 amps.
If a buck boost has a 16-32 secondary, does that mean the incoming voltage will be reduced by 16 or 32 volts, or just one or the other depending on 120 or 240 input? The tables from the manufacturers don't show that you can reduce 255 to 223 (255-32), just 239.
I am confused! Please help!