BX900R-CN self tests six times in six hours

[Anonymous user]

Hello. I've had this unit for two years now and it's done a fine job. It's actually a replacement for a unit that I had for a year previous but the fan started getting very loud and APC replaced it for me. Yesterday, I noticed the self test occur quite a few times throughout the day. There are no warning lights or sounds at all, just this abnormally high rate of self testing going on. I tried a test today myself by unplugging all computer equipment and plugging in lights and so forth so I would know how much wattage I'm demanding (totaled 300 watts), and pressed the button on the unit to run the test three times. The unit passed the tests and returned to normal function, with no indication that there's a line or battery problem. I might add that there's been only one errant self test the unit has performed today (that I'm aware of as I'm not sitting at the computer 100% of the time). I had hoped that the self tests might not really be self tests but rather poor line power and the unit was "doing it's job" and that the second or two that it came on was all that was needed to combat the noisy/poor power. I didn't notice lights or anything else flicker though. It seems like a real puzzler and I'm very tempted just to go pick up a newer (and while I'm at it as it couldn't hurt, more powerful) ups as I'm uncomfortable having my computer connected to something that's acting oddly. So if anyone here has any suggestions or advice why this ups is doing what it's doing, I'd appreciate hearing about it. Thanks in advance.....

[BillP]

Good day Vid,

I would like to know what is going on with your UPS that made you think it is doing a self-test. Does it go to On Battery and then back to Online? Do you also have any software, PowerChute Personal Edition that might be running on your PC? Using a software, this would tell us if there is any power interruption that causes your unit to act like this.

Also, if it is seeing minute power interruption or harmonic distortion we can change the sensitivity to a lower value so that the UPS would have a wider acceptable distortion.

[Anonymous user · Accepted solution]

Thanks for the reply JonPro.

I don't know if it's a self-test but it acts exactly the same as when the unit is first turned on and performs its self-test. The unit went to ON Battery for a second, tops, then back to online. I never got an audible alarm of any sort or any other warning lights come on. I assume as it's a short duration event, and not an actual power loss, that this is normal (no alarms). Now, it may have been a particularly bad day regarding my electricity supply but I've never seen this happen in over five years of using an ups. After posting this, I got a few more of these "events" however, yesterday I only had one that I know of.

I've never used the powerchute software as I'm always at or near my computer and am able to shut down and have never been interested in monitoring anything. However, yesterday I did install it and it told me that the unit it providing 118 watts to my idle system, I added another device with a constant 110 watt draw, did a test with the software and unit's button and after a few of those again, all passed. Sadly, now that any past info that would have helped is not available as the software is only now installed and what happened in the past is left to speculation. At least for the future I'll know what's going on. Oh, and I've always used and am still using the medium setting for sensitivity. I understand what you're suggesting by setting it to "low" but the manual and software state it's not really recommended for computer equipment so I'm a tad reluctant to try it. The thing is....if the unit is doing what it was meant to do, and that's protect me from low/high/dirty power, I'm absolutely OK with it doing what it did. It's better than stressing my computer (which is why I use an ups now as I had a computer die years ago using only a surge protector and I'm certain the occasional poor power was the culprit) and was mostly just concerned whether or not this behavior which I'd never experienced was "normal". Now if it was happening ten times a day, day after day...that'd be a problem I guess.