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UPS won't hold Server up

UPS won't hold Server up

UPS won't hold Server up

I have a APC UPS 1000 on the back of a 3 year old server, and the other day when we lost power to the building the server just shut off like it had been unplugged from the mains. The UPS did not hold it up at all. I have since tried another UPS and have the same problem. I can't have 2 dodgy UPS' ??
Could this be a Server PSU problem rather than the UPS. There is nothing else plugged into the UPS except the server and the monitor.
Can anyone lend any ideas on this?

RE: UPS won't hold Server up

It is possible to have bad batteries after 3 years and it is possible to have 2 bad UPS units.

You don't say what models we are talking about.  For a server and that size ups it would typically be a Smart UPS.  That should have a load indicator on it, a battery charge indicator, and it should do weekly self tests and tell you if the batteries need to be replaced.  If you are running the UPS above half it's rated load it's very possible that the batteries are just not up to the task.

I would start by trying to test the UPS's with a non critical load.  An old PC is a good place to start.  If you have an old CRT monitor that will probably add at least another 100 watts to the load.  Let the UPS run on battery for awhile and see how it does.

I find the cheap little KilloWatt monitors are an easy way to measure what actual load you have on the UPS.


If you happen to have a cheap UPS then the rating on those is usually kind of bogus and it is unlikely they will perform anywhere near what they are rated.


RE: UPS won't hold Server up

Hi JimInKS,

The UPS that was on originally was a 650 which was repalced with a APC SmartUPS 1000, which is the one that does not hold it up. Interestingly i have done a test this lunch time on the 1000 and it works fine with 2 PC's a laptop and a flat screen monitor, and it holds them up fine for a while. To me that does point to something in the server, maybee the PSU's.
What do you think?

RE: UPS won't hold Server up

What is the wattage on the PSU on the server? Is there more than one PSU? A server PSU could well be 700-900 watts all by itself, add in a monitor and that's all she wrote. Computers only tend to have between 200-300 watt power supplies, laptop will be very low, and LCD will be low compared to a CRT.

RE: UPS won't hold Server up

What is the load indicator on the UPS showing?

RE: UPS won't hold Server up

You mention that the server is 3 years old. How old is the UPS ?
as JimInKS mentioned, you should be using a SmartUPS, which will let you see what the load is, the expected runtime with the current load, and let you do tests. If the server runs OK on normal AC power, the PSU is OK. You've got UPS issues, likely battery condition - for a server in a business, you really need a UPS that lets you know what it's doing, tests itself regularly, and tells you when it needs maintenance.
Give yourself a preview at home - for $100 or so, you can get a 650VA APC Smart UPS that connects to your PC via USB, and provides the management software. I run my main PC on it, as well as the DSL modem, the Netgear router with WiFi, and a NAS box.
Once you've gotten the feel of the features at home, you can spec out the model you should be using at the office, and get approval based on personal experience.

Fred Wagner


RE: UPS won't hold Server up

  Also, you should be aware, that some ups' have switched outlets ( battery backup) and unswitched ( no battery backup). The unswitched outlets just have line conditioning. So if you plug your equipment into the wrong outlets, they are not actually on battery backup even if plugged into the ups.

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