Smart UPS 1000VA SMT1000I Battery temp question

[Anonymous user]

Ok so I literally just bought this new UPS, SMT1000I, being used in residential home.

Powered on fine, initial battery test fine.  I also then decided to just cut the power at the mains for a while just to make sure its working ok.

Here's my question, its been fairly warm day but not too hot. Ambient temperature is 28.4C.  After the battery finished charging back to 100% I noticed the on-screen reported battery temp creeping up and up and up.

At the moment its showing 36.9C and I hope it doesn't go any higher!.   This seems a bit unusually high to me.  Does that seem normal for battery to be around 37C when the ambient temp (reading taken very close to the unit) is 28.4C?

In the instruction manual it says this UPS can run up to an ambient temp of 40C, but I imagine that if the ambient temp actually exceeded 32C, the battery temp might hit 40 and the unit will automatically disconnect it 😕

Thoughts please?

Additional info, the units situated close to back wall, but plenty of space above and sides (good 2 feet either direction).  The front side of the unit where I assume the battery is placed feels nice and cool to the touch, and more warm towards the back of the unit under the grill holes.

It's powering a PC, total draw no more than 230W max, average 165W.

Another thing, the box was a bit damaged and battered when it arrived, but the internal contents looked 'ok', unit was still held within the polystyerene bits. Could the battery have been damaged during transit?

[Anonymous user]

Something else I forgot to add and ask. I'm running this UPS on a power cable which has a 5 Amp fuse, is that ok? or should it have a 13Amp fuse in it?.  It said on the back of the unit 7.5A max.

[BillP]

Has anything changed since your post?

I see most of our units running around 30ºC and they are in a lab cooled environment. Since yours is in a home, it sounds like it is not. Also, temperature is going to rise when the UPS is charging and when it is running on battery or even boosting/trimming voltages. Your temperature seems a little warm but not super hot. This is also the temperature inside the UPS so it is most likely going to be a few degrees higher than the ambient temperature around the case of the UPS.

I don't think what you are seeing is indicative of any type of problem based on what you are describing. If you touch the battery with your hand (be careful), is it excessively warm against your hand?

As far as the power cable, I would assume if anything, this does not adhere to a local code but you'd only risk popping the fuse if your load goes all the way up to 7.5A max so as long as you don't anticipate going over 5A, it'd be OK. So basically, you lose the ability to go to the 7.5A because the fuse would pop first at 5A.

[Anonymous user]

The temp settled up to 37.8C and has pretty much stayed there ever since.  Is it ok for this unit to be reporting the battery temp as 37.8C all the time?.

There is plenty of airspace around the unit, but it is sitting directly on fairly thick pile carpet, do you think or would you advise raising it slightly off the carpet?

[BillP]

In an ideal situation, the ambient temp would be less than 70F/21C, but in a home environment. this is fairly normal. The battery will usually be 10-15º higher than the ambient.

Putting the UPS on a hard surface would probably help some, but nothing here concerns me. The UPS does not have the ability to disconnect the battery at 40ºC and we know that the battery temp will always be higher than ambient. Everything you may see documented on our end is in relation to ambient temperature.

[Anonymous user · Accepted solution]

Ok thank you Angela, thats very helpful.

The confusion for me was reading in the manual about ambient room temp max being 40C, but then when I saw the LED screen report battery temp close to that when the ambient temp was about 28C I got worried maybe the unit would shut down the battery use if it hit 40C internally.

It would be good if with the instructions that come with the unit they better explain the internal temperature reading and what the safe range for that is, rather than just the ambient temp, that would also help diagnosing issues when the unit is in good ambient temp, but the battery might be unusually high temp.

Weirdly, today is a very warm day again, its 28C in my room, yet the battery temp is now only 33.1C, its actually gone down a lot!. I wonder if maybe because it was a new unit and everything was settling thats why the temp stayed quite a bit higher at first.

Anyways, all is fine now, seems to be working great so thank you