UPS will not power computer during power failure

[lti]

I have an old APC 500VA UPS that will not power the computer from the battery. When it tries to perform a self-test or switches to battery due to poor power conditions, the computer instantly shuts off and the UPS produces a continuous beep.

When this happens, power is being switched on and off to the battery backed outlets in half-second intervals. The computer, monitor, and DSL modem are connected to the battery backed outlets, and all three will attempt to power on when they receive power during this period. If I turn the UPS off and back on, the computer is able to power on like nothing happened.

What causes this? Do I just need to replace the battery?

[shovenose]

Re: UPS will not power computer during power failure

500VA is not 500W. Your computer and monitor and all the peripherals attached may be drawing too much power!

[dood]

Re: UPS will not power computer during power failure

Is the "replace battery" light on?

Try testing it with a light load instead of the entire PC.

I'll put my bets on the battery.

[kc8adu]

Re: UPS will not power computer during power failure

sounds like a sick battery.how old?

[lti]

Re: UPS will not power computer during power failure

The battery is due for replacement. The battery was replaced three years ago. There are no alerts saying that the battery is bad. The UPS is about six years old and has worked fine with this computer until now. I wanted to see if there is something wrong with the UPS itself instead of just having a bad battery.

I am using a cheap generic battery from Batteries Plus. The original APC battery still had some life left in it after three years, but it is also more expensive. I was hoping that it would only need a new battery.

[shovenose]

Re: UPS will not power computer during power failure

Batteries Plus has sold me many crappy products. I don't go there anymore. So that's probably your issue. I would go for a legit APC battery if I were you.

[Evil Lurker]

Re: UPS will not power computer during power failure

I say screw both of them and get a big honking deep cycle marine battery and mount it outside the chassis with some extension cables.

[kc8adu]

Re: UPS will not power computer during power failure

+1
i pull out plenty of year old werker and xtreme+ from ups units.
junk.the only good agm/gel they stock are the us made ones with the bolt head looking caps.those are east penn/deka.and of course the oddesy and optima.
is yours the old metal cased apc?
if so the external battery trick is good.if its the cs (cheap shit) plastic thing its junk.even a recall due to fire.

Batteries Plus has sold me many crappy products. I don't go there anymore. So that's probably your issue. I would go for a legit APC battery if I were you.

[lti]

Re: UPS will not power computer during power failure

This is a Back-UPS ES500. It is a cheap home model. I don't need anything better for an old Dell Dimension 4550.

I think the battery is a Werker brand. It was a very cheap battery. The genuine APC batteries are also cheap Chinese batteries with an APC label applied over the original markings. I don't think the $30 generic batteries are much worse than a genuine APC battery that costs twice as much. Obviously, the $25 Werker batteries suck.

[larrymoencurly]

Re: UPS will not power computer during power failure

Several months ago, I found that a couple of 4-5-year-old batteries that always passed their backup's built-in test couldn't power their computers for more than 30-60 seconds.

BTW, the Friday Fry's ad features a 550VA (330W?) APC backup for $35, after rebate.

[ThePCDoctor]

Re: UPS will not power computer during power failure

Several years ago, I was given an old 600VA, APC UPS because the original batteries were leaking out on the customer's carpet. I took out the old batteries and cleaned up the mess in the case and connected an extra car battery to it just to see if it would actually work. It did.
Here is my current battery for that USP:


These are the cheapest batteries I could buy at Wal-Mart and they come with a great warranty. The UPS keeps them fully charged with NO problem. I connected the batteries to the UPS with 12ga wire, with a 30A fuse, in line.

On the last test I performed on this UPS it ran for seven hours, before it even started a slow BEEP to tell me the batteries were getting low. I figured that was good enough and restored line power, to end the test.
This old UPS backs up my 27" TV, Cable box, DVD Recorder, one table lamp and a small personal fan, for a little comfort during extended power outages.
If the cable goes out, I also have the outside antenna amplifier and digital decoder box connected to the UPS, so I can still get Weather Reports.

So, connect a 12v battery to that old UPS and see if it still works.

Good Luck,
The Doctor

[joshnz]

Re: UPS will not power computer during power failure

A month or 2 ago there was a switch over/or shot in the towns supply (around 2 secs of bad power) my ups failed to keep my system up, a new battery fixed it.

[kc8adu]

Re: UPS will not power computer during power failure

the es will not take the external trick.heatsinks too small and timer in firmware.
the best batts i have used were the enersys/yuasa.
check for recall and if not on the list buy a quality battery.
or look for a free/cheap older apc.like a back-ups or smart-ups 650.still 12v.a lighter socket and a 15a breaker so you can charge phones,ect in a pinch.runtime limited by how much lead you want to hook up.

[ThePCDoctor]

Re: UPS will not power computer during power failure

It would seem like some brands of UPS are sensitive to the battery being used with them.
I tried the lead acid battery trick on a 'Cyber Power' ups and it was a NO-GO.

A friend got a very large APC UPS that required 24vdc, lead-acid batteries to power it.
Originally it had four large 6v batteries, but they had died.
He connected two 8D truck batteries to that USP and it ran just fine.

The APC Brand UPS's seem to be less sensitive to what battery is connected to them, than other brands. That gives the user a lot more flexibility as to what battery to use.

Cheers Mates!

[Longbow]

Re: UPS will not power computer during power failure

You are misinformed. The purpose of a UPS is to give the system enough time to shut down properly. It is not designed to operate the equipment during a power failure. As such, a large system may require a large number of batteries to supply adequate power for a short time while it shuts down.

[dood]

Re: UPS will not power computer during power failure

You are misinformed. The purpose of a UPS is to give the system enough time to shut down properly. It is not designed to operate the equipment during a power failure. As such, a large system may require a large number of batteries to supply adequate power for a short time while it shuts down.

Or, in datacenters, to run the equipment until the generator starts up and has stabilized enough to take load.

[RJARRRPCGP]

Re: UPS will not power computer during power failure

+1
if its the cs (cheap shit) plastic thing its junk.even a recall due to fire.

Yep, the plastic ones are cheap! On one day on May, 26, 2002, IIRC, my Phillips 107S wasn't even getting power so I unplugged it then plugged it back in and when I plugged it back in, got a blue spark with a pop! Then all the battery outlets were dead permanently!

The plug blades are a hazard, one of them dislocate and causes an arc that kills the backup outlet circuit.

[lti]

Re: UPS will not power computer during power failure

The software finally told me that the battery needs to be replaced because it is over three years old. This UPS isn't intelligent enough to determine that the battery is dead if it won't power the computer at all.

The purpose of a UPS is to give the system enough time to shut down properly.

That is what this UPS is used for. The original battery works for this purpose.

[KeriJane]

Re: UPS will not power computer during power failure

I studied UPS's a few years ago for this beastie Mac Pro.

Here's my findings, for what it's worth:

The metal APC SUA SmartUPS series produce a sine wave output which is what our PSUs are designed for. They're big, very heavy and expensive but get the job done.

Practically everything else out there produces either a square wave or a "simulated sine wave" (stepped square wave) which is not as friendly to our PSUs. Short term use like that for an orderly shutdown should be fine but extended operation could be hard on the PSUs of connected equipment.

Here's where I ran into trouble....

When most computers start, including the Mac Pro, there is a brief period while things are energized in sequence. This spreads the startup current over time and reduces the sudden demand all at once that would otherwise occur.

The 1st-gen Mac Pro has a charming characteristic: A cold boot is sequenced but waking from Sleep is not! This absolutely causes anything less than a very hefty UPS to overload.

Why is startup important for a UPS? Because if you connect the UPS to a USB port, it will wake the computer from sleep when power goes out and cause an overload.

It seems that the minimum UPS for the MP's 1kw power supply is the SUA1500 which works out nicely.
The same could hold true for any system with a 1kw PSU though.... the UPS has to handle a wake from sleep which can be as much or more than a boot up. Unless of course the system never sleeps.


Oh well... an expensive Mac Pro needed an expensive UPS. No big deal, but it took a while to figure that out.

I look at it like this: the UPS will be around a very long time. Might as well get a great one rather than waste time and money with a cheap one..

[kc8adu]

Re: UPS will not power computer during power failure

tested a apc xs1300 today.
hooked up some wheelchair batts and loaded it up close to max.ran cool and no timer!
its an all plastic design though.one of my business partners adopted it and 2 100ah high rate ups batts.