SUA1500RM2U internal fault or just need batteries?

[Anonymous user]

HI all. I am trying to determine if my UPS just needs new batteries or has an internal fault. Recently the fan in my SUA1500RM2U began to run constantly. This started a few days after the unit was mistakenly taken off AC power which then consequently drained the batteries completely. I checked the knowledge and found the 4 parameters that cause the fan to run.

1. The UPS is on battery.
My UPS is not on battery

2. The UPS is charging the battery.
Maybe, but all the time???

3. The UPS has a load greater than 75%.
The load on this UPS is less than 25%.

4. The internal temperature of the UPS has reached greater than 140 degrees F (60 degrees C).
Possibly. Read on...

Ok, here's what I've noticed and tested.
- I did the brain-dead test. Fan came on immediately once turned on and connected to AC power.
- I have turned the unit off via the power switch but have left it plugged into AC power for over 8 hours. The fan still runs.
- After the unit was powered up for a while, I removed the top of the case. I found that the 2 batteries closest to the transformer were much warmer than the 2 the furthest away. Also, the transformer was extremely warm, almost too hot too touch. Are these conditions normal?
- 3 batteried showed +/- 13.3 volts on a multimeter. 1 showed 11.5v but the voltage came up to at least 12.5v after 5 minutes of not being on charge.
- Upon noticing the warm batteries and transformer, I powered down the UPS and unplugged it for the night. Up to this point I've never seen any fault indicators lit. The battery charge indicator was at 100%. Around 20 hours later I powered up the UPS. The batteries failed the power on self test and the charge indicator is 40%.

APC tech support has told me they believe there is an internal fault and I should trade in the UPS. I am not so sure it is an internal fault. I think it's a good possiblity the batteries have gone bad and need to be replaced, but did they die from old age and from being mistakenly discharged, or were they overcharged by internal fault? Is the reason the batterys and transofrmer are warm, and the fan constantly runs is because the unit is trying to charge bad batteries? The unit is more than 4 years old.

Anyone care to post their thoughts on whether I should replace just the batteries, or the whole unit?

Here is my support ticket number: Question Reference #080814-000375

Thanks,

Doug

Message was edited by: horsepow3r

Message was edited by: horsepow3r

Message was edited by: horsepow3r

[Anonymous user]

Just as a reminder, I don't represent APC, so please don't call them and said I said this and that...

HI all. I am trying to determine if my UPS just needs new batteries or has an internal fault. Recently the fan in my SUA1500RM2U began to run constantly. This started a few days after the unit was mistakenly taken off AC power which then consequently drained the batteries completely. I checked the knowledge and found the 4 parameters that cause the fan to run.

You're right that the fan runs when it's on battery power, under heavy load and when the battery is charging. The charging current is monitored and the fan turns on when it reaches some current, then off when it falls below some preset limit. The two points are not the same, so that it won't hunt back and forth between on/off.


I found that the 2 batteries closest to the transformer were much warmer than the 2 the furthest away. Also, the transformer was extremely warm, almost too hot too touch. Are these conditions normal?
3 batteried showed +/- 13.3 volts on a multimeter. 1 showed 11.5v but the voltage came up to at least 12.5v after 5 minutes of not being on charge.

13.3v vs 11.5v is only supposed to happen immediately following a completely drained battery, but the difference is rather excessive. Heavy discharge is bad for battery and if it was already on its last leg, the last heavy discharge can kill it. The transformer can get quite hot, so that's normal.

How long has it been in use? Has it ever been stored unused in storage?


Upon noticing the warm batteries and transformer, I powered down the UPS and unplugged it for the night. Up to this point I've never seen any fault indicators lit. The battery charge indicator was at 100%. Around 20 hours later I powered up the UPS. The batteries failed the power on self test and the charge indicator is 40%.*

APC tech support has told me they believe there is an internal fault and I should trade in the UPS. I am not so sure it is an internal fault. I think it's a good possiblity the batteries have gone bad and need to be replaced, but did they die from old age and from being mistakenly discharged, or were they overcharged by internal fault? Is the reason the batterys and transofrmer are warm, and the fan constantly runs is because the unit is trying to charge bad batteries? The unit is more than 4 years old

Then, there's a very good chance you've exhausted the useful life of battery. 4 years is getting there.

Monitor the voltage across the battery as the self-test kicks in. If it plummets, then you've got a bad pack. If it was an internal fault drawing excessive current to the point of this happening, you'd blow the fuse... The first two digits of serial number gives you the year and the following two gives the week of the year the unit was made.

The float voltage is quite high and the internal temperature is quite warm, so these batteries don't live the most comfortable life. 4 years is not an unreasonable lifespan.

You might be able to locate the bad battery within a pack, but don't EVER replace just one battery. Replace the entire pack. That pack is quite expensive, so you can save quite a bit by buying four 12v 9Ah batteries on eBay yourself, or buying a pre-built compatible pack.

[Anonymous user]

Actually, I am convinced you're right now. Batteries are warping from heat. I'm putting this thing into the garage for now. I want to get rid of it. Does anyone buy these things and refurb them? I will not be trading it in for another, that's for sure.

[TheNotoriousKMP_apc]

It's possible that this was caused by both an unnecessary discharge and overcharge.

If the UPS immediately turns the fan on after braindeading and restoring AC, then it's definitely a fault.

I would recommend either the repair through Coastal Business Machines, or Trade-UPS. Looks like all the troubleshooting was covered.

[Anonymous user]

Hmmmm. Before I did the last power on self test in my original post (when the battery charge was 40%), I did a brain dead reset. After pluggin into AC power, the battery light came on and the unit gave the one minute bad battery beep during POST. Since then (about 2 hours) the bad battery light has not come off. It indicates batteries are fully charged. The fan **was not** on the few times I checked in that 2 hour time period. What is going on lol? Looks like bad batteries.

Sorry, I am not convinced. Where's KVAr . I would like his opinion.

Message was edited by: horsepow3r

[Anonymous user · Accepted solution]

Thanks KVar. You replied just after my last post, the one about the battery casings appearing like they are warping from heat so you probably didn't see it. Any thoughts on why 2 of the battery cases are warping? I once again pulled the top cover off of the UPS because I was hearing a short screeching noise, even when not plugged in. KInd of sounded like a short dog whine. In fact, I thought it was my dog giving a short whine until I investigated. 🙂 I thought it might be the batteries exhausting gases, but remembered they are sealed. Any thoughts?

In response to your questions, the UPS was in storage for approx 5 months recently. I have used the UPS for 3 years. I bought it used so I am not sure how old it is. APC says it's over 4 years old.

I would love to be able to just replace the battery pack but due to the bttery swelling issue, I'm not sure that this is the correct remedy. What should I do?

Thanks,

Doug

Message was edited by: horsepow3r