APC SmartUPS 1000 draining batteries without power outage?

[Gustavus]

I have three computers, each on it's own APC SmartUPS 1000. On a couple of occasions one of the computers has been off and the battery charge lights on it's UPS showed the batteries as being discharged. There had been no power outage (our clocks were all OK and the other two UPS's were running and fully charged) If I disconnect the UPS and allow the batteries to fully charge again, the self test shows the batteries as being good. Self test places a load on the unit and then monitors the voltage drop while the unit is providing AC to the load from battery supply. This is a pretty dependable test of battery condition.

I have also run a brute force check by unpluging the power cord to simulate a power failure and watching the UPS pick up the supply for the computer. Everything appears normal. The computer places a low load on the UPS in normal use -- in other words the UPS is overkill for this computer. Only the first (lowest) LED is lit on the load indicator -- out of five LEDs.

I have no idea of what could be happening. Do any of you have a suggestion of what could be going on?

Besides passing the self test and my brute force test of power failure, I should mention the batteries are relatively new and were replaced at the same time as the batteries in the other two identical SmartUPS 1000's.

 

[TonyDigital]

Hi,


The unit could be acting up because the batteries are bad, the charging circuit is bad or there are board problems.


You should try and determine the run time you are getting with the load. So let's say your computer puts a load of 200W on the UPS, you should get approximately 45 minutes.


Place the 200W load on the UPS, and pull the plug. How much run time are you getting? If you're getting close to 45 minutes, your batteries are good and the problem is somewhere else. If you're getting a 5 minute run time, the problem is with the batteries.


Give this a try and let us know,



Tony,

 

[bruceb]

First thing is to swap the battery pack in the unit that is acting up with one that is not acting up. See if the unit that had the problem still does. If not, bad battery. If it does, the charging circuits in the APC unit are bad.

 

[RadiclDreamer]

Or it could be compensating for low input voltage

 

[Gustavus]

Thanks for the helpful replies. I had assumed that the self test etc. was enough to rule out the batteries, but a 300 watt resisitive load caused the UPS charge indicator to go down to one LED in only a few minutes so I have a bad battery -- or more. I have an automotive load tester for batteries so will pull them and check them individually. Looks like with your help and advice the problem is close to being solved.

 

[TonyDigital]

Hi,

It's definitely a good idea to test the battery with a strong load. Even though the light on the UPS goes down, it doesn't necessarily mean the battery is dead, it could be that the UPS needs a calibration to resync with the capacity of the battery.


Try the load and let us know.



Thanks,
Tony

 

[Gustavus]

New batteries fixed the problem. I let them charge for three hours to top off the charge and then loaded the UPS with the 300 watt resistive load. Held up beautifully as it should with the power cord unplugged. I sure appreciate the suggestions since I had convinced myself the problem was something other than batteries.

 

[TonyDigital]

Hi,


Glad to hear you were able to get the problem resolved easily!



Good luck and all the best!


Tony

 

[Gustavus]

Tony,

Since you are obviously very familiar with the APC UPS's, I have a question/request I hope you can help me with. Several years ago we had a major power outage while we were not at home. I did not have Power Chute installed at the time to turn off the computers at the end of battery holdup. I was using them to just bridge the frequent power anomalies we have here in rural New Mexico. All three Smart UPS1000's ran down of course. When I disconnected the loads and allowed the batteries to recharge the systems were no longer operable. A tech support person at APC talked me through a long procedure to reset the microprocessor. I tried to take notes, but they are far from complete -- or comprehensible -- to me now. They start with "Go to hyperterminal programs/accessories/hyperterminal" and then continue for a page and a half of detailed steps. The procedure did work and the three microprocessors were all reset. Do you know where I can find and download a more complete and detailed set of instructions for doing a microprocessor reset in the UPS1000?

Thanks again for your help.

PS
I also have three of the APC Back_UPS XS 1500's running in the lab but have never had a problem with any of them. My cable modem is on an APC Back_UPS 300. You can see I rely on APC.

 

[TonyDigital]

Hi Gustavos,


There are several methods of resetting the microprocessor in the APC Smart-UPS 1000. If your UPS is not operating properly after a power outage and shows that the battery is drained even though it has recharged, I would recommend a simple hardware calibration.


The hardware calibration is one of the most accurate methods of getting your UPS to register the proper battery capacity and run time.


To do the hardware calibration, do the following:

1. Charge your APC UPS to 100%
2. Put 32% Load on the unit (measure this through PowerChute, and make sure the load is constant)
3. Unplug the Comm Cable (so your PC doesn't get a shut down command)
4. Pull the power cord from the wall, so the unit begins to operate on batteries
5. Let the batteries run down completely, until every last light is OFF
6. Unplug the 32% load from the UPS
7. Plug the UPS back into the wall, and quickly hit the OFF button (when power is resupplied to the UPS, it will try to turn back on, so make sure you turn it off)
8. Let the unit charge for 4-6 hours



The above process should reset the UPS for you and provide you an accurate run time. It will resync the microprocessor to the batteries.


Occasionally this will need to be done twice, to ensure that the UPS has the correct run time and understands how to charge the battery fully.


Thanks,
Tony

 

[Old Hippie]

Originally posted by: TonyDigital
Hi Gustavos,


There are several methods of resetting the microprocessor in the APC Smart-UPS 1000. If your UPS is not operating properly after a power outage and shows that the battery is drained even though it has recharged, I would recommend a simple hardware calibration.


The hardware calibration is one of the most accurate methods of getting your UPS to register the proper battery capacity and run time.


To do the hardware calibration, do the following:

1. Charge your APC UPS to 100%
2. Put 32% Load on the unit (measure this through PowerChute, and make sure the load is constant)
3. Unplug the Comm Cable (so your PC doesn't get a shut down command)
4. Pull the power cord from the wall, so the unit begins to operate on batteries
5. Let the batteries run down completely, until every last light is OFF
6. Unplug the 32% load from the UPS
7. Plug the UPS back into the wall, and quickly hit the OFF button (when power is resupplied to the UPS, it will try to turn back on, so make sure you turn it off)
8. Let the unit charge for 4-6 hours



The above process should reset the UPS for you and provide you an accurate run time. It will resync the microprocessor to the batteries.


Occasionally this will need to be done twice, to ensure that the UPS has the correct run time and understands how to charge the battery fully.


Thanks,
Tony

Nice info Tony!

Thanks and welcome to Anandtech! :thumbsup:

 

[TonyDigital]

Hi,


Thank you, I hope the information is useful to someone. If anyone has any questions about APC UPSs I would be more than glad to try and help.


All the best,
Tony

 

[Gustavus]

Thanks Tony. I have filed your info with the SmartUPS manuals -- just in case I ever have the need to reset the microprocessors again.

My wife's computer has not had a problem since I replaced the batteries.