Computer shuts down immidiately !!

[BillP]

When I have a power failure or simply unplug my APC 550ES from the wall outlet my PC and everything plugged onto it shuts down. No beeps nothing. The green light goes off and on at a slow rate. The monitoring software says that the battery is charging and is at 97 %.
On one occasion the APC did switch over to Battery and the Computer shut down properly after 5 minutes. But not once again has it done that. It basically works like a power strip with no battery. My system has a 5oo watt power supply and is Pentium 2 duo with two hard drives and a Gforce 8800 video card. I also tried turning my PC off and then unplugging the backup ups and still noticed that all power is lost on my motherboard,hot USB and the amber light on the monitor.

Would I be on the right track to say that this has something to do with transfer time between line power and Battery during switch over that the power supply on my computer can`t handle? If thats the case why is this APC recommended for desktop PC`s?

Adam

[TheNotoriousKMP_apc]

Adam,

With no load attached, if you unplug it from the wall to force it on battery, does it remain on, or just power off altogether? It could be possible that with your setup the VA/Watt draw is higher than what the UPS can handle, or near the UPS' capacity and therefore as soon as it goes to battery, the UPS powers off due to an overload.

[BillP]

Thats what I thought but no its not overloaded for sure. However I kept switching the the unit on and off with the computer off and then on and also unplugged the APC a couple times with computer not attached and then set it back up to normal and bravo ...it works fine again. I have tried turning the power in the house off and the battery is taking over just fine and no prob so far. It seems to me that the unit trips up its self some how that the battery does not kick in as it should with a power failure. But resets after turning it on and off a few times. I did return the unit to the store and they gave me another one that did the same thing but is now working. At least for now. Beats me.

[Anonymous user]

Unfortunately im having the very same problem .
So far , out of about 10 blackouts, 2 times SUA1500I UPS failed to switch to battery in time . What is intereseting is that i can turn off power manually as many times as i want , UPS will allways switch to battery in time as he should. But when the real power failure happens ,then it sometimes fails 😞

And it is definitely not a overload problem im having here. UPS is loaded only to 20% .
Power supply is old HEC 350 Watt.

Any ideas what can be a problem here ?

[Anonymous user]

a-n-y-o-n-e ?

[Cap1_apc]

Hey Ves, thanks for bumping this back to attention.

Are you using any version of powerchute? Or is this an issue of the UPS dropping the electric?

What is the serial on the UPS? The last time the battery was changed (if any)?

[Anonymous user]

Hi Cap1.
Yes im using Powerchute Business latest version.
Is the serial number really necessary ? Since it was bought second hand ...
But the batteries are brand new.

[TheNotoriousKMP_apc]

Ves,

When was the last time a software initiated calibration was done? Have you done the brain dead procedure on the UPS? Does the UPS ever report communication loss?

[Anonymous user]

Hi The Notorious 🙂
Sorry for a late reply .

"When was the last time a software initiated calibration was done?"
I guess the answer is - never ? 😞 Or you mean the one Ups Starts every 2 weeks itself ?

"Have you done the brain dead procedure on the UPS?"
Are you making fun of me ? 😄

"Does the UPS ever report communication loss?"
Yes , i have experienced it twice in about 2 months .

Please excuse my bad English and my complete lack of understanding in UPS 😞

Do you believe my UPS can be faulty ?

[Anonymous user]

1 thing i can tell for sure . next time i will buy an UPS from local store ... it will cost me twice as much but at least i will be on a safe side 😄

[TheNotoriousKMP_apc]

Ves,

A software initiated calibration would be performed through PowerChute Business Edition. It is a "runtime calibration" and should be found under Diagnostics. That will re-calibrate the battery for you.

The braindead procedure is as follows:
1. Turn off and disconnect all attached load
2. Turn off UPS and disconnect from utility power
3. Remove all communications cables
4. Depress the OFF button for approximately 4-6 seconds until you hear a click.
5. Power everything back on.

This will ensure full communication on EITHER USB or Serial, whichever cable you plug in first has full bi-directional communication.

I don't think the UPS is faulty, but I think those steps need to be considered before further speculation/troubleshooting.

[Anonymous user]

Why have I not read here that SOME computer power supplies simply can not handle even an extremely short time of transition between being powered and switching to battery? It is in you APC knowledge base, but buried deeply there. That's what your tech help are telling me in recent emailings. And why are people NOT forewarned of this before they buy their APC units????????? Then they could make informed decisions.

[BillP · Accepted solution]

There have been a few various posts like this one... They may have different thread names though, since posters can choose whatever titles they want, so they very well may be difficult to search for.

Forewarned by whom? Most of the time when people call in for sizing, the first thing an APC rep asks for is info about the equipment the UPS is for, including info about the power supply. They aren't computer power supply manufacturers though so they can't know exactly what each PSU can handle. In addition to transfer time, some units don't like the power output a UPS has when on battery (pure sine wave vs. step-approximated sine wave).

I agree that it can be difficult to find things in the kbase depending on keywords... Please see [this one|http://nam-en.apc.com/cgi-bin/nam_en.cfg/php/enduser/std_adp.php?p_faqid=20] for more info and perhaps for future reference.