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220/120 VAC Temp Svc Boxes: Can I adapt them to 440 3phase?

220/120 VAC Temp Svc Boxes: Can I adapt them to 440 3phase?

220/120 VAC Temp Svc Boxes: Can I adapt them to 440 3phase?

(OP)
Out utility services company has a number of 220 VAC-powered temporary services boxes.  Each 220 VAC box is waterproof, is powered from a 220 VAC 20 amp cord, and supplies 6 120 VAC 20 amp utility plugs for hand tools and lights during outages.  

Fine.  They would work, except almost no customers have 220 VAC on site - that voltage can only come from diesel generators and diesel welder trailers as "auxiliary" power.   

440 VAC/3 phase is always available however.  Without building and shipping a dedicated transformer (440/220) with each 220 VAC services box, is there any reliable (and obviously safe and sane) way to connect two of the 220 utility boxes to the clients' 440 input?   Physical connections, wire sizes, and breaker trip values, etc, need to be properly designed, but I'm just trying to look at the concept right now.      

DC theory would hold you can tap off of  2x resistors across the 440, and split the voltage in half.  But that would cause continuous power losses, and assume some constant current (load) from each tap.    A 120 volt utility services box will see irregular loads at irregular times through every shift for many shifts, so splitting the 440 would not appear to be correct.    

RE: 220/120 VAC Temp Svc Boxes: Can I adapt them to 440 3phase?

BITE THE BULLET AND GET AN ELECTRICIAN TO SPEC A TRANSFORMER.
Larger projects often distribute 480 VAC or 600 VAC and have a transformer built in to each temporary power center.
Nobody has 110 or 220 on site. The standard supply voltages are multiples of 120 Volts. 120 V, 240 V, 480 V and 600 V.
Your temporary boxes are fed from a 120:240 Volt source, not 220 VAC or 240 VAC.
 

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: 220/120 VAC Temp Svc Boxes: Can I adapt them to 440 3phase?

But in direct answer to your question, NO!

And please heed waross's advice and find a professional to look at this for you. It's clear this is beyond your level of expertise and had you attempted to do that, you may have killed someone.

"Dear future generations: Please accept our apologies. We were rolling drunk on petroleum."
— Kilgore Trout (via Kurt Vonnegut)
  
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RE: 220/120 VAC Temp Svc Boxes: Can I adapt them to 440 3phase?

(OP)
Done.  Thank you.

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