Hospitals and capacitor banks

[mshields]

When I was peddling switchgear I saw alot of hospital applications that used switched capacitor banks on the main service. Not sure what drove it. It doesn't strike me as a motor intensive application and therefore not of particular concern. It seems obvious to me however that I'm missing something.

Should a switched cap bank typically be provided at the service to a hospital and if so why? thanks,

Mike

 

[Energy-Miser]

When I was peddling switchgear I saw alot of hospital applications that used switched capacitor banks on the main service. Not sure what drove it. It doesn't strike me as a motor intensive application and therefore not of particular concern. It seems obvious to me however that I'm missing something.

Should a switched cap bank typically be provided at the service to a hospital and if so why? thanks,

Mike

It may be to supply power while the generator is ramping up in a utility power failure. I know that flywheels are being used for this purpose too in some places, where no gap in power can be tolerated, such as in data centers. e/m

 

[bob]

When I was peddling switchgear I saw alot of hospital applications that used switched capacitor banks on the main service. Not sure what drove it. It doesn't strike me as a motor intensive application and therefore not of particular concern. It seems obvious to me however that I'm missing something.

Should a switched cap bank typically be provided at the service to a hospital and if so why? thanks,

Mike

I recently made some PF measurements at a hospital in my area. They had some capacitors installed but the PF reading showed that they could same some money by a further improvement of the PF. I do not know all of the load but they were heavy in A/C load.

 

[crossman]

IMO those capacitors would have to be for PF correction. There could be a substantial motor load considering AC and heating, ventilation, sumps, and whatever else I am not thinking of. And then there is the older ballasts for lighting too.

As for supplying power while the generator is ramping up? Hmmm.... On a DC system maybe, but not hooked into the AC service.

 

[ghostbuster]

Just finished a design for a hospital cap system.Caps are generally used to increase P.F. and save money on utility bills(16 month payback).Used non-switched units because demand load is generally constant throughout the year.

 

[Energy-Miser]

IMO those capacitors would have to be for PF correction. There could be a substantial motor load considering AC and heating, ventilation, sumps, and whatever else I am not thinking of. And then there is the older ballasts for lighting too.

As for supplying power while the generator is ramping up? Hmmm.... On a DC system maybe, but not hooked into the AC service.

After seeing the last few posts, I agree that power factor correction is the more likely reason for those caps. I have read however somewhere that caps are used as stop gap in emergency power to give the generator time to come online. Maybe their output is run through inverters, not sure exactly on the details of such a system. e/m.