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#185338 - 03/11/09 03:00 PM Service size for Chiropractic Office: X-Ray  
Wardey  Offline
New Member
Joined: Dec 2004
Posts: 1
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 05:18 PM Re: Service size for Chiropractic Office: X-Ray [Re: Wardey]  
Yoopersup  Offline
Member
Joined: Mar 2003
Posts: 822
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.


#185341 - 03/11/09 06:15 PM Re: Service size for Chiropractic Office: X-Ray [Re: Yoopersup]  
electure  Offline


Member
Joined: Dec 2000
Posts: 4,259
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





#185343 - 03/11/09 06:26 PM Re: Service size for Chiropractic Office: X-Ray [Re: electure]  
Yoopersup  Offline
Member
Joined: Mar 2003
Posts: 822
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

Last edited by Yoopersup; 03/11/09 06:31 PM.


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