Smart UPS started to frequently run the fans, why?

[Anonymous user]

Hi,

in my home office I've got an APC Smart UPS 1500, it's about 8 years old and went through one battery replacement a couple of years back.

It's sitting in a room with 15-20 degrees C ambient temperature, and there's not very much load attached to it (it was dimensioned for an old-school workstation, for an iMac plus a few peripherals it's quite an overkill).

Starting a few days back, the fans have started to turn on for what feels like a minute with an interval of half an hour or something like that.

Usually the only time the fans started running was when there was a power surge, a power outage, or a self test; in my area power surges are quite frequent, which is why I use a good UPS to protect my equipment.

Question is, what could the reason for the frequent fan spinning be? Do I need to be worried about something?

Thanks

[BillP]

I would feel the side of the case and see if it feels abnormally hot as a first step. Can you confirm the model on the back of the unit (on the white sticker) is SUA1500?

This UPS would turn it's fan on if it's charging the battery, on battery, internal temp is above 104º, or if the load is above 75%. So, one of those may be true (either erroneously or not) or the fan can be on its way out too.

For example, maybe the UPS erroneously thinks the UPS is charging constantly. Are you able to connect the PowerChute software to the UPS via USB (if supported) or serial? apcupsd is also an option as a software that can read UPS data to see if we can check the status of the UPS if the outside case does not feel extra warm.

[Anonymous user]

The model is SUA1500I.

The load is definitely not above 75%, and neither does the unit wrongly believe that to be the case, the five load LEDs are all off.

The front half of the unit, towards the front panel with the LEDs and the on/off switch is noticeably warmer than the back half.

I could hook up the unit to my computer via USB, but so far I have only used the UPS support built into Mac OS X; if there's a reasonably good PowerChute for Mac OS X 10.9 I'll give it a try.

(Software from 3rd party peripherals on Mac is often so bad that I don't even bother to install it if it's not absolutely necessary, haven't checked how APC's offerings fare.)

The fan itself seems to be working fine, on one side it's pushing warm air out of the unit.

So from your list that leads the "constantly charging", which could presumably be due to a hardware defect ... or could something like this happen when the battery is a couple of years old and I haven't "calibrated" the unit by doing a full discharge in quite a while?

Thanks for your help

[BillP]

You're welcome. You need PowerChute Business Edition which I wouldn't use on Mac (I forget if it even works). PowerChute software for Mac overall does not fare very well Alternatively, apcupsd (via apcupsd.org) I think will be a good solution for you. It is nice and light and should work with Mac and serve our purpose.

If the UPS is constantly charging, it could be due to battery health and/or a hardware issue. Hard to tell without seeing the data via the softtware but if that's the case, you did not miss any maintenance that would cause this scenario. If anything, the UPS battery management could be better and we have greatly improved it UPS generation after UPS generation.

[Anonymous user · Accepted solution]

Ok, apcupsd was a good hint, I got it up-and-running really quickly.

(To reiterate, regrading the hardware setup and the ambient temperature, nothing has changed, but since a couple of days ago the fans start spinning frequently (more than once per hour) for a short period of time (feels like a minute).)

/etc/apcupsd> apcaccess

APC      : 001,043,1057

DATE     : 2014-02-05 21:57:43 +0100

HOSTNAME : localhost.local

VERSION  : 3.14.11 (31 January 2014) darwin

UPSNAME  : myups

CABLE    : USB Cable

DRIVER   : USB UPS Driver

UPSMODE  : Stand Alone

STARTTIME: 2014-02-05 21:57:29 +0100

MODEL    : Smart-UPS 1500

STATUS   : ONLINE

LINEV    : 239.0 Volts

LOADPCT  :   0.0 Percent Load Capacity

BCHARGE  : 100.0 Percent

TIMELEFT : 304.0 Minutes

MBATTCHG : 20 Percent

MINTIMEL : 10 Minutes

MAXTIME  : 0 Seconds

OUTPUTV  : 239.0 Volts

SENSE    : High

DWAKE    : -01 Seconds

DSHUTD   : 090 Seconds

LOTRANS  : 208.0 Volts

HITRANS  : 253.0 Volts

RETPCT   : 000.0 Percent

ITEMP    : 37.8 C Internal

ALARMDEL : 30 seconds

BATTV    : 27.1 Volts

LINEFREQ : 50.0 Hz

LASTXFER : No transfers since turnon

NUMXFERS : 0

TONBATT  : 0 seconds

CUMONBATT: 0 seconds

XOFFBATT : N/A

SELFTEST : NO

STESTI   : 14 days

STATFLAG : 0x05000008 Status Flag

MANDATE  : 1980-01-01

SERIALNO :

BATTDATE : 2005-05-26

NOMOUTV  : 230 Volts

NOMBATTV :  24.0 Volts

FIRMWARE : 601.3.I USB FW:1.5

END APC  : 2014-02-05 21:57:49 +0100

[BillP]

Well, I don't see anything too shocking but, the internal temp is 100ºF (37.8ºC). On this model of UPS, the fan will come on when the internal temp is 104ºF to cool the unit down. Is it possible for you to check the current temp readout when you notice the fan on? To me, this is the only thing that I suspect at this point since since it is very close to the threshold currently. Everything else looks normal (load percentage, UPS online, and battery voltage is OK so I don't suspect overcharging - charge is also 100%).

[Anonymous user]

The fan just started up again, and this time the temperature is higher:

ITEMP    : 39.6 C Internal

So presumably the question is, why does an otherwise perfectly (?) functioning unit suddenly start heating up more than before?

[BillP]

Most of the time this is the battery in my experience, especially since this has no load. I know you felt the side of the case but can you remove the front bezel and perhaps take a look at the battery and feel it too - verify no swelling or see if it's hot to the touch?

The UPS would be doing a self test every two weeks anyway to see if the battery was on it's way out but sometimes it can still heat up but not fail its self test (which only compares a voltage drop while on battery) which is more likely to pass if no UPS load on the battery.

Also, it is OK (if you can afford to) to maybe disconnect the UPS battery for some time (it will just beep at you though) and see if the temperature drops and you'll have no battery back up.

Just a few ideas.

[Anonymous user]

Ok, I removed the front bezel and then the metal plate between it and the battery; the battery is quite warm to the touch, well above body temperature, but I could keep my hand on it for as long as I want without burning myself (I haven't got anything to measure the temperature).

Is that normal?

It doesn't look deformed.

Thanks again!

[Anonymous user]

The main question is, do I need to be concerned that it will explode or start a fire or leak acid or something?

[BillP]

With a lead acid battery, there is always I think a remote possibility of leaking acid. I don't think you should be worried but I would certainly keep an eye on this. It is good that we are paying attention and you should be able to catch any problems before they become as severe as you mention. Just make sure the area is well ventilated. I know you mentioned the battery is a "few" years old - can you be more specific? They should last about 3-5 years. If a few is more like 4-5 years, well it is still possible the internals of the battery are heating up and the battery is nearing its end of life. Typically, these battery issues develop over time rather than just spontaneously leaking or cracking.

[BillP]

I apologize for butting in here, and I don't question and will defer to your expertise as always, but isn't a hot battery an indication that something is not quite right?  I ask this because I just checked the batteries in all three of my UPS systems and they run cool to the touch.

I wonder if there is possibly an ambient airflow issue due to dust bunnies accumulating over the years or an installation that prevents proper air circulation?

[BillP]

Yes, that is why I wanted clarification on how old it is and also mentioned the ventilation. The batteries also were warm but not warm enough to burn anything so that is why I mentioned that if anything, we may be catching the problem early which is good. My UPS battery is fine and it runs a little warm - it is not ice cold.

[Anonymous user]

Update: Yesterday evening I unplugged the battery and turned the unit off. In the morning the battery was luke warm.

Then I unplugged the unit from the wall socket and left it for a couple more hours.

When I connected everything again, the fans did two longer rounds of whirring, and since then everything's ok again, i.e. the battery is only hand warm and no fans.

Either this was a glitch that lasted a fortnight, or something strange is going on...

[Anonymous user]

Yes, BlueSky, a hot lead acid battery is not very confidence inspiring... At least now I know that it's not normal 🙂

[BillP]

Maybe this will help? http://www.apc.com/whitepaper/?wp=39