APC UPS batteries swollen
Jim shedden
I just bought a used UPS, as is. Looks in fine condition and is
3000kva for $100. The batteries need replacing and seem to be swollen
or stuck in the case (5U rack mount). Really can't seem budge them at
all, and I don't want to break them and make a mess. From what is
visible, I see no leakage, but a crack along the seam of the case on
one. It bulges a bit at that point, so I think they're swollen stuck.
There look to be 4 x 12Volt 17AH sealed lead acid batteries in there.
Any suggestions greatly appreciated. I would hate to hack out the
battery bucket because it is all riveted, but if I have to I will. I
don't see any way to push them out from the back, and if necessary to
do so, I may have to drill a hole but would probably hit a battery in
the process.
Other thoughts may include silicone spray and heat guns. I really
don't have an aproach yet. Would they shrink if I charged them?
What might cause the swelling? Overcharge? Cold temperature storage
without charging? Failure to replace when necessary?
Thanks in advance for any ideas!
Regards,
Jim
Jeff Liebermann
shedden) wrote:
>I just bought a used UPS, as is. Looks in fine condition and is
>3000kva for $100. The batteries need replacing and seem to be swollen
>or stuck in the case (5U rack mount). Really can't seem budge them at
>all, and I don't want to break them and make a mess. From what is
>visible, I see no leakage, but a crack along the seam of the case on
>one. It bulges a bit at that point, so I think they're swollen stuck.
Yep. A while back, I ended up with about 35ea APC 1400RH SmartUPS's
with swollen batteries. Only two had leaked, but all were an ordeal
to extract. I ended up making a battery puller out of an iron bar. I
would reach in behind the battery and pull them forward as a group
(there were 4ea 12V 7AH batteries). To release the batteries from the
side walls, I used a large paint scraper or putty knife. I had to
beat on the knife with a hammer in some cases.
>What might cause the swelling? Overcharge? Cold temperature storage
>without charging? Failure to replace when necessary?
Overcharging. In this case, marginal design.
--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831.336.2558 voice http://www.LearnByDestroying.com
# je...@comix.santa-cruz.ca.us
# 831.421.6491 digital_pager je...@cruzio.com AE6KS
budgie
<je...@comix.santa-cruz.ca.us> wrote:
>On 27 Oct 2003 19:19:57 -0800, james....@baesystems.com (Jim
>shedden) wrote:
(snips)
>>What might cause the swelling? Overcharge? Cold temperature storage
>>without charging? Failure to replace when necessary?
>
>Overcharging. In this case, marginal design.
Very often, in the search for a balance between battery lifetime and
discharge recovery time, the UPS manufacturer favours the latter. The
charging circuitry on some is little short of criminal negligence, and
overcharging followed by premature SLA failure is fairly normal.
Jim shedden
> On 27 Oct 2003 19:19:57 -0800, james....@baesystems.com (Jim
> shedden) wrote:
>
> >I just bought a used UPS, as is. Looks in fine condition and is
> >3000kva for $100. The batteries need replacing and seem to be swollen
> >or stuck in the case (5U rack mount). Really can't seem budge them at
> >all, and I don't want to break them and make a mess. From what is
> >visible, I see no leakage, but a crack along the seam of the case on
> >one. It bulges a bit at that point, so I think they're swollen stuck.
>
> Yep. A while back, I ended up with about 35ea APC 1400RH SmartUPS's
> with swollen batteries. Only two had leaked, but all were an ordeal
> to extract. I ended up making a battery puller out of an iron bar. I
> would reach in behind the battery and pull them forward as a group
> (there were 4ea 12V 7AH batteries). To release the batteries from the
> side walls, I used a large paint scraper or putty knife. I had to
> beat on the knife with a hammer in some cases.
>
> >What might cause the swelling? Overcharge? Cold temperature storage
> >without charging? Failure to replace when necessary?
>
> Overcharging. In this case, marginal design.
Hi Jeff,
Thanks for the response. Excellent URL, by the way! I checked out a
few of your stories, quite amusing.
I'll let you know how I make out. Any hints on preventing the
catastrophic failure of the replacement batteries? I have access to a
fluke scopemeter and a DC current probe for it. Can the charging
circuit be easily "dummy loaded" and checked out? Care to share your
experience?
At $200 for replacement batteries, I want to make sure that I'm not
putting them in for destruction (need UPS, not 'Easy Bake Oven'. I'd
rather not learn quite so expensive a lesson by destruction!).
Regards,
Jim
kc8adu
lots of sla batts do this at end of life.
btw you can spend the same money you would on replacement sla's and get some
deep cycle batts to use externally.
"Jim shedden" <james....@baesystems.com> wrote in message
news:b2bb7a22.03102...@posting.google.com...
James Sweet
>
> I'll let you know how I make out. Any hints on preventing the
> catastrophic failure of the replacement batteries? I have access to a
> fluke scopemeter and a DC current probe for it. Can the charging
> circuit be easily "dummy loaded" and checked out? Care to share your
> experience?
>
A Scopemeter is way more than you need even, though the DC current probe
will simplify things somewhat. Just put in new batteries and put the current
probe around one of the wires to them, or just unhook one wire and run it
through the amps jacks on a standard DMM. Plug the unit in so it's charging
the batteries and measure the current. Let the batteries charge overnight
and then measure it again, that should give you the full charge current as
well as the trickle charge, compare it to what the manufacture recommends or
to standard guidelines for the batteries.
Bill Janssen
offices with that same problem. There was a routine to check the plates, in clear
cases, and when they started to touch the case the battery was replaced.
Before the routine inspections there were a few broken cases.
Bill K7NOM
**THE-RFI-EMI-GUY**
entire battery case in lots of dry ice to cause the batteries to shrink
a bit. Once you are sure they have soaked a while, use a heat gun to
work on the metal chassis and cause it to expand. I assume that they
battery case and the electronics can be seperated for this operation.
Jim shedden wrote:
--
Joe Leikhim K4SAT
"Jazz is not dead. It just smells funny." -F.Z.
Jim shedden
>
> Regards,
> Jim
Hi,
Just a quick note to close out the thread. Thanks for the replies.
I did a major disassembly of the ups. All the parts except the
batteries visually look fine, so I'm making the investment in new
batteries. The old ones did have swollen plates and actually cracked
the battery case, jamming themselves in REAL GOOD.
Should anyone be stuck in this situation, I don't recommend doing this
unless you are experienced at working on LIVE possibly LETHAL
circuitry. Follow all manufacturers precautions (and take it to
them!). The batteries in the back can't be disconnected because the
front ones block them and may contain quite some power.
I actually entered through the left side wall. Some rivets have to be
drilled (don't forget to vacuum out any shavings!), then the left side
panel can open. More rivets will open the left wall of the battery
bucket and relieve the pressure. The fronts are out now and the backs
are disconnected. I'm confident I can retrieve them as well.
It may be possible to solve this without removing the top panel and
all the circuitry and wiring attached. Just go in through the left
panel. If you can do it, it is far safer because your biggest hazard
will be 12V at high current. You won't see any inverter or control
circuitry.
Regards,
Jim
budgie
shedden) wrote:
>Hi,
>
>Just a quick note to close out the thread. Thanks for the replies.
(snip)
Jim, I hope that when you reassemble it you go the extra yard and
either fit spacers (if practical) to avoid the tight fit *next*time*
(because there WILL be a next time), or replace the rivets with
threaded fixings.
Jim shedden
Hi,
Once you know the how to open the case, with a cordless drill and pop
riveter, it is a fairly quick and painless job. I hope to get 3 - 4
years out of the batteries that I ordered. After that, maybe I'll be
lucky enough to be hooking up a 24 volt fuel cell (I can dream, can't
I...).
Your suggestion has merit though. Sheet metal screws would have been
removable, but you would have sharp points protruding into the battery
compartment. If you reached in for the back cells during normal
replacement, you could get cut. There is probably a fastener that
would do it, but I can't think of what it would be at the moment.
What I didn't expect was the size of the transformers in the unit.
When I bought it, I figured the majority of the weight would be the
batteries. It is still very heavy with the batteries out. I built a
little scooter for it and it lives on the floor.
Now for the 30 amp branch circuit...
Regards,
Jim
budgie
shedden) wrote:
>m...@privacy.net (budgie) wrote in message news:<3fa1c3bf...@news.individual.net>...
>> Jim, I hope that when you reassemble it you go the extra yard and
>> either fit spacers (if practical) to avoid the tight fit *next*time*
>> (because there WILL be a next time), or replace the rivets with
>> threaded fixings.
>
>Hi,
>
>Once you know the how to open the case, with a cordless drill and pop
>riveter, it is a fairly quick and painless job. I hope to get 3 - 4
>years out of the batteries that I ordered. After that, maybe I'll be
>lucky enough to be hooking up a 24 volt fuel cell (I can dream, can't
>I...).
>
>Your suggestion has merit though. Sheet metal screws would have been
>removable, but you would have sharp points protruding into the battery
>compartment. If you reached in for the back cells during normal
>replacement, you could get cut. There is probably a fastener that
>would do it, but I can't think of what it would be at the moment.
I suppose that seeing it would make it all clear to me, but if there's
clearance for a pop rivet then I would have expected a riv-nut or
similar to also fit.
James Sweet
>
> What I didn't expect was the size of the transformers in the unit.
> When I bought it, I figured the majority of the weight would be the
> batteries. It is still very heavy with the batteries out. I built a
> little scooter for it and it lives on the floor.
>
Yes these tend to use 60 Hz magnetics making them *very* large and heavy,
I'm really not sure why they do that, these days it seems like it would be
cheaper to use a small high frequency transformer and then rectify and
filter that, then electronically modulate it to a 60 hz signwave.
Jeff Liebermann
shedden) wrote:
>Thanks for the response. Excellent URL, by the way! I checked out a
>few of your stories, quite amusing.
Amusing? I'm serious. Thanks for the kind words, but the web pile
needs a massive overhaul and update. Many of the docs have not been
updated for years.
>Any hints on preventing the
>catastrophic failure of the replacement batteries?
Yeah. Keep the charge current low and the temperature down. In my
never humble opinion, methinks APC designed some (not all) of the
UPS's to charge quickly. After a power outage, they wanted the
batteries to be fully charged quite rapidly. Would you want to wait
perhaps a full day for a large battery pack to fully charge after an
extended power outage? I suspect the alleged overcharge is a side
effect of rapid charging.
It's also helpful to know what causes swelling. Take one of the
batteries apart and you'll notice the swelling always occurs
perpendicular to the plates. That's because charging and discharging
a battery is a destructive phenomenon. Lead is literally removed from
the plates and disolved into solution during discharge. Lead is
replaced (plated) onto the plates during charging. If the lead is
replaced unevenly, erratically, or too rapidly, it tends to build a
rather lumpy mass in the spacers between the plates. Eventually,
these can even short a cell. The phenomenon is worst when you
discharge a gel cell completely, and then rapidly recharge it.
Overheating will also cause the plates to warp. Here's where the
debate starts. Batteries of any type, including gel cells do not get
warm until they overcharge. I've performed experiments with extremely
rapid chargeing of NiCd, NiMH, and Gel Cells, to see what happens when
a battery is charged at rediculously high currents. Each one responds
slightly differently and with varying degrees of success (and
explosive effects). However, one common thing I've noticed is that
the temperature does NOT rise until the battery is fully charged.
Therefore, I can deduce (i.e. guess) that if the gel cells are warm,
they're being over charged. The reason it's a guess is that I haven't
done much testing with gel cells. Most of my experiments have been
with AA NiCd and NiMH.
In the case of my APC 1400RH UPS's, I use only external batteries.
These are big, size 27, 100(?) AH, Gel Cells. However, I do not
program the UPS to know about the larger batteries. It thinks it's
charging a smaller battery pile, and therefore seems to limit charge
current to what I would consider a more conservative level.
>I have access to a
>fluke scopemeter and a DC current probe for it. Can the charging
>circuit be easily "dummy loaded" and checked out? Care to share your
>experience?
Overkill. Use the built in diagnostics to display the current drain,
or just use a VOM (volt-ohms guesser) in the ammeter range, to display
DC current and voltage. The real trick will be to calculate the
desired charge current and maximum terminal voltage. Incidentally,
you can really kill a gel sell with exessive charge terminal voltage,
even if the charge current is low. The absolute maximum charge
voltage is usually printed on the gel cell.
>At $200 for replacement batteries, I want to make sure that I'm not
>putting them in for destruction (need UPS, not 'Easy Bake Oven'. I'd
>rather not learn quite so expensive a lesson by destruction!).
You don't want to know how much money I've burned learning about the
characteristics of those APC 1400RH boxes. A brand new set of
internal batteries lasted exactly 6 months before they too were toast.
If I had left them in the box, they would have swelled and eventually
died.
--
Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
(831)421-6491 pgr (831)336-2558 home
http://www.LearnByDestroying.com AE6KS
je...@comix.santa-cruz.ca.us je...@cruzio.com
Brian Friedl
week ago that I needed to replace batteries. Sounds good, they were
two years old. Well, while I was waiting for the 2 12v 7.2Ah in series
to come in, my UPS suddenly turned off and would not turn back on. I
was away from the computer at the time, so I have no idea how long the
UPS was in this state. Depression of the on button would cause the UPS
to emit a dying whine from the small alarm speaker.
At this point, i figured it was because of the dead batteries, and
needed good ones to power up. Removal of the batteries revealed
battery 1 appeared fine and registerd 12.54vdc. Battery 2, however,
has a overheated, bulging cell and registered 10.36vdc. Voltage
readings of the two batteries in circuit while UPS plugged in (but
still cant turn on) showed 7vdc?!? Batt 1, in circuit, read 12v, but
batt 2 read -4v? wtf?
Problem solved. Replaced batteries with UPS unplugged and got a
surprise arc. Status LED's on front came on for a second, and heard
relays click on and off. Plugged UPS in thinking all was well, and
heard speaker beep, then some crackling sounds and finally the dreaded
smoke. I immediately unplugged UPS from live power and battery power.
Smoke appears to have originated from some square caps near the
regulator ICs. Since old batteries didnt spark or anything, i tried
plugging them in for kicks.