UPS dead, how do I go about troubleshooting/fix it? (Dell UPS 2700R)

nle

Member
Oct 24, 2012
201
11
18
I got a Dell UPS 2700R (J727N) in 2017 (I got it "for free" when I bought a server rack). At that time, I lived in a small apartment and did not have the fuse (16A) or space (noise-wise) to run it. It did work perfectly back then, and I played around with it for about a week before putting it in storage (yes, I know not ideal for the batteries).

Fast forward to this year, we moved, and I now live in a house with a basement (i.e server room) and I would like to use this UPS.

I tried to power it on, and then nothing… it will not power on at all. AFAIK it should turn on regardless – even if the batteries are dead/faulty.

I've tried researching online, but I can't really find anything about this model not turning on at all.

How would you guys go about troubleshooting (and hopefully fix) it?

Thanks!
 

BoredSysadmin

Not affiliated with Maxell
Mar 2, 2019
816
308
63
isn't it a 230v UPS? If so, is this is the electric power you have in your house?
 

nle

Member
Oct 24, 2012
201
11
18
I'm from Norway, and our electricity runs on 230v. :)

The manual (PDF) states it is available for 120v and 208v also:
UPS Output Power 120V 208V230V
2700W30A20A16A

(And I have powered it up earlier, three years ago)
 

vl1969

Active Member
Feb 5, 2014
628
74
28
I am not sure about that specific UPS, bit some UPS will not turn on if battery it completely dead.nin fact my apc 1500 unit will not turn on on fully empty battery pack.
How I know? Well I have 2 units like this. I got them for free when I bought a rack on eBay.
They were laying around for 3 years untill I got around to set all up. Well I plug it in and not a pip fromnk enof them. Second start beeping and indicate bad battery. I took both of them apart, one that was dead the battery expanded so badly I barely get the tray out. The one that was still "alive" also was expanded but not as badly.
Just for fun I plugged the tray from that one in a dead unit and it started beeping as well.
Got a set of new cells, for one of them and it have been happily running my home lab for 2 years now.
 

nle

Member
Oct 24, 2012
201
11
18
Thanks for that, but I think this model is made to be run with faulty batteries – as long as it is connected to a power source. Hope someone can prove me wrong.

I do have a multimeter – even though I barely know how to use it – so I will try to check the batteries and report back.

In the meantime, please continue with your inputs. :)
 

nle

Member
Oct 24, 2012
201
11
18
So I just got around to use the multimeter.

I put it on DC (afaik that is what I should do on batteries) and measured: 34,8V
Screenshot 2020-08-24 at 13.52.02.jpg

That is quite low, it has 8 x 12V batteries, but it has been sitting for a couple of years, so I guess that's to be expected?
The UPS has 8 x Yuasa NPW45--12 (datasheet) batteries, so in theory – if all is top-notch – I should be seeing 96V.

For the record, they all look good. No bulging, etc.


Screenshot 2020-08-24 at 13.53.11.jpg
Screenshot 2020-08-24 at 13.53.26.jpg

I also measured the battery connector coming from the UPS (i.e the part that plugs into the batteries) and I got 25,4V. Is that correct? :oops: The UPS is unplugged, and I thought I shouldn't get anything.

What do you guys think, is it as easy as to just replace the batteries (would cost around 300 USD)?
Am I missing something? Anything else I should check?

(I also thought this model would run without batteries, but I hope I'm wrong)

(disclaimer: I'm in over my head on this, but doing my best.)