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Phase Convertor Sizing #195763
08/20/10 05:18 PM
08/20/10 05:18 PM
Yoopersup  Offline OP
Joined: Mar 2003
Posts: 840
MCA 74 on compressor unit (all mts taken into account).
240 v single phase to 240 v 3 phase.
40 hp convertor .
input Aprox 127 amps
outputaprox 100 amps.

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Re: Phase Convertor Sizing [Re: Yoopersup] #195777
08/22/10 04:10 AM
08/22/10 04:10 AM
twh  Offline
Joined: Mar 2004
Posts: 928
Regina, Sask.
I'm guessing you're looking at a rotary converter. Do the motors need to be de-rated? The math looks off between single phase input and 3 phase output.

Re: Phase Convertor Sizing [Re: twh] #195779
08/22/10 01:15 PM
08/22/10 01:15 PM
Tom  Offline
Joined: Jan 2001
Posts: 1,044
Shinnston, WV USA
Any chance of doing this with VFD's? Appropriately sized VFD's can convert a single phase input to three phase.

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Re: Phase Convertor Sizing [Re: Tom] #195780
08/22/10 03:18 PM
08/22/10 03:18 PM
Yoopersup  Offline OP
Joined: Mar 2003
Posts: 840
This is a Full HVAC unit was ordered wrong. MCA on name plate 74 amps single point hookup.
So need about 80 amps or so on three phase side.
As starteres ect are all ready in the package looking for 3 phase power imput. Vendor told us 40 hp unit well do the trick just checking.


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