-----Original Message----- From: centos-bounces@centos.org [mailto:centos-bounces@centos.org] On Behalf
Of
Les Mikesell Sent: Monday, February 02, 2009 5:20 PM To: CentOS mailing list Subject: Re: [CentOS] Emergency rescue help needed
I've been buying from the Smart-UPS and Back-UPS range. Those should be ok, shouldn't they?
That depends on how important it is to never fail. If it is extremely important, you might want something with redundant components like the Symmetra line. These are designed to keep working with some failed components and to allow you to replace parts with the equipment on bypass but still running.
The UPS-units serve group-server machines. If one or two should go down it's not really a biggie, although it's not good either. Not critical in any way. Still, one would expect the UPS-units to last more, or at least not fail due to the electronics. Besides, I'd never be able to get the funding for the Symmetra line UPS:es. 8-/
All in all about a handfull of them. They're quite pricey... 90% of them suffered some kind of a circuit board failure. Not what you'd
usually
expect from a UPS, rather you'd expect the battery to give up first. I
bought
them over a few years, so it shouldn't be a bad batch or something like
that.
You might blame one or two on bad components, but this sounds like something is wrong with the input power at your location. I assume they are lasting at least through the 2 year warranty period. We have at least a few dozen of them and haven't noticed any pattern of problems other than aging batteries. Are you tracking the in/out power levels on the smart units to see what they have to deal with?
The voltage has been fairly constant here over the years since I started using UPS and logging the voltage and stuff, 238V more or less constantly. It rarely drops below 236V or over 240V. We mainly use the UPS:es to have controlled shutdowns should the power fail entirely - We had some issues a few years back while they built a new school the other side of the road when the power went up and down for a uyear or so, and the diesel-generators didn't start up as expected. This whole building where I work is supposed to be a wartime hospital with power-backups up to yinyang. But it failed when we needed them... #=;-(
It might be that the power is too high, although the standard is 240V in Europe AFAIK. Or the UPS-units *may* have been rated for the previous lower voltage-level at 220V, but that sounds a bit farfetched IMO. Unless the units were a (very much) older batch that APC dumped on us...