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#185338 - 03/11/09 12:00 PM Service size for Chiropractic Office: X-Ray
Wardey Offline
New Member

Registered: 12/04/04
Posts: 1
Loc: Palm Harbor, FL
Trying to size a service for a chiropactors office and not sure on the demand for an X-Ray machine. The X-Ray Tech say's he needs an 100 Amp 220V circuit. Here's what I have existing:
100 Amp 3 Phase Service w/ 1 Alum Conductors

So do I figure the X-Ray machine at 100% demand?

And my load calcs would be:
12 receptacles @ 180VA = 2160
640sq.ft. @ 3 VA = 1920
Heat @ 10,000 VA
Sign Ckt. @ 1200 VA
X-Ray Machine @ 24,000VA
Total 39,280 VA

39,280VA / 240V = 163.66 Amps / 1.73 = 94.60 Amps

Correct? The 100 Amp service should be suffecient?

Thanks !!!

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#185339 - 03/11/09 02:18 PM Re: Service size for Chiropractic Office: X-Ray [Re: Wardey]
Yoopersup Offline
Member

Registered: 03/04/03
Posts: 826
Loc: Michigan
if your using 240 x 1.73 it must be a high leg delta??
IF ITS A 120/208 Y (most common) it be 208 x 1.73 =359.84
Just checking.

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#185341 - 03/11/09 03:15 PM Re: Service size for Chiropractic Office: X-Ray [Re: Yoopersup]
electure Offline


Member

Registered: 12/24/00
Posts: 4229
Loc: Fullerton, CA USA
Yoop,
Wrong answer.

If 208 volts you DIVIDE it by 1.73
Not MULTIPLY it.

39,280VA / 208V / 1.73 = 109.15 Amps




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#185343 - 03/11/09 03:26 PM Re: Service size for Chiropractic Office: X-Ray [Re: electure]
Yoopersup Offline
Member

Registered: 03/04/03
Posts: 826
Loc: Michigan
39280 divide by 359.84 =109.15962
Sure looked like devideding to me?????

1.73 x 208= 359.84
39280 Divided by 359.84


Edited by Yoopersup (03/11/09 03:31 PM)

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