size of generator

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At the animal hospital my wife techs at, they are wanting a generator. They have an X-ray machine that has a momentary output of 140 amps at 220 volts. It dims the entire clinic when first engaged. Since this is the biggest power draw there, what are the watts needed to support this draw?

 

[Mendonsy]

They would need about 32kw to support just that X-ray not including the rest of the facility. A full 200 amp service (probably what they have now) would require 46kw.

 

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They would need about 32kw to support just that X-ray not including the rest of the facility. A full 200 amp service (probably what they have now) would require 46kw.

So just for the X-ray machine, they would need an output of 32,000 watts?

 

[Mendonsy]

YEP! The math is simple enough, Watts = Volts * Amps.
The question is do they really need to use that Xray machine when running on a generator?? The rest of the facility might run on a 20kw generator.

 

[KWentling]

This is a case where you would want to get an expert involved in choosing a generator. It may not be as simple as amps x volts. Maybe some inrush to consider and will the generator supply clean enough power for the electronics.

 

[buickanddeere]

This is a case where you would want to get an expert involved in choosing a generator. It may not be as simple as amps x volts. Maybe some inrush to consider and will the generator supply clean enough power for the electronics.

Power factor has to be considered . Start multiplying volts X Amps and the number will come out different than the watts for inductive and capacitive loads.
Is X-raying critters going to be a priority when utility power is down ?
What are the other electrical loads?
A generator will have more bog and light dimming than utility power because of governor response time.
This looking like at least a 50KW generator.

 

[Industrial Toys]

That really sucks! It's not good having a generator not loaded up. Natural Gas or LP would probably be a better choice for this application then diesel.

A Vet Clinic bought my old Onan 15KW PTO unit.

 

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Power factor has to be considered . Start multiplying volts X Amps and the number will come out different than the watts for inductive and capacitive loads.
Is X-raying critters going to be a priority when utility power is down ?
.

This is a pertinent question and is one the hospital needs to consider. 2 yrs ago the power went out there for 5 days on a wind swept 27" dump. 5 days w/o an X-ray machine proved to be rather exasperating for this company as X-rays are a first line course for about 40% of what comes into the clinic. Between cancer, what animals eat that they shouldn't and internal abcesses and disease, it's used quite bit and just about every day. An 8000 watt generator powered the rest of the clinic at that time. A stand by unit this large is around 14K. Hook up is probably another 5. They have to decide about this expense by comparing what they lost in turn away business along with the chances of getting another 5 day loss of electricity .

 

[SPYDERLK]

This is a pertinent question and is one the hospital needs to consider. 2 yrs ago the power went out there for 5 days on a wind swept 27" dump. 5 days w/o an X-ray machine proved to be rather exasperating for this company as X-rays are a first line course for about 40% of what comes into the clinic. Between cancer, what animals eat that they shouldn't and internal abcesses and disease, it's used quite bit and just about every day. An 8000 watt generator powered the rest of the clinic at that time. A stand by unit this large is around 14K. Hook up is probably another 5. They have to decide about this expense by comparing what they lost in turn away business along with the chances of getting another 5 day loss of electricity .

It sounds as if the xray has an initial surge. What condition causes the surge? Is it only on startup, or does it occur as the xray is taken each time? If its only a startup surge - charging a capacitor bank or something - maybe the machine can be soft started. This would lower the 140A max drain and lengthen the time only slightly.

 

[ultrarunner]

Also sounds like the x-ray is pushing the capacity of they utility power...

At the 32,000 square feet Out Patient Surgery and Imaging Center there is one 600V 1200 amp 3-phase breaker.

The Emergency Power is supplied by a 600V 150 amp Emergency or 125 amp Prime rated Diesel 3-phase generator.

No lights ever dim....