UPS battery replacement schedule

[Warren Post]

I just replaced the battery in my UPS, and notice that the old one was
swollen and hard to remove. Searching this NG and elsewhere on the net, I
see this means that the battery had reached the end of its life some time
ago and should have been replaced sooner. Okay, replacing the battery
when it reaches the end of its life cycle instead of waiting until it
obviously fails is fine by me.

So how do I know when to replace a UPS battery? This particular UPS has
no self test feature and no com port with which to communicate with the
computer, and I don't want to toss perfectly working equipment into the
landfill just because it lacks bells and whistles to make my life a
little easier.

 

[Jamie]

I just replaced the battery in my UPS, and notice that the old one was
swollen and hard to remove. Searching this NG and elsewhere on the net, I
see this means that the battery had reached the end of its life some time
ago and should have been replaced sooner. Okay, replacing the battery
when it reaches the end of its life cycle instead of waiting until it
obviously fails is fine by me.

So how do I know when to replace a UPS battery? This particular UPS has
no self test feature and no com port with which to communicate with the
computer, and I don't want to toss perfectly working equipment into the
landfill just because it lacks bells and whistles to make my life a
little easier.

A good test would be to pull the AC plug!


http://webpages.charter.net/jamie_5"

 

[Warren Post]

A good test would be to pull the AC plug!

Well, I'm seeking a way to identify when a battery needs to be replaced
*before* it fails the pull-the-plug test. By the time it reaches that
point, the battery has badly overheated and swollen. Surely I need to
have replaced the battery before that.

 

[John Robertson]

I have several ways to test batteries. The easiest is to install one
or two 100 watt incandescent lamps into the UPS output, unplug the UPS
from AC power, and see how long it will run. I do this when the UPS
is brand new, and again at erratic intervals. I also measure the
charging current to the battery, which is sometimes higher than I
would consider acceptable. These are also the ones that suffer from
premature battery death from overcharging and/or overheating.

You can also test the batteries outside of the UPS by using a 12v
automobile headlight or similar load. Again, compare operating time
with a new battery.

I recently purchased a West Mountain Radio CBA-II battery tester:
<http://www.westmountainradio.com/CBA_ham.htm>
Charge the battery and then run it through the tester. Compare with
a new battery of the same type. The problem is that the basic unit
does not work well with large batteries yielding odd results due to
connector contact and cable losses. The voltage is measured at the
tester end, not the battery.

I also plan to use the CBA-II to match UPS batteries. I tend to
purchase a fair number of "used" lead acid UPS batteries. The savings
is substantial but there are hazards. One is installing two
mismatched batteries in series.

I have used an ESR meter to check the condition of lead-acid batteries,
but haven't kept up with the practice. Was thinking an easy test would
be to have test points mounted outside of the UPS that one could use to
access each battery for an in-circuit ESR reading. Charting the results
would probably tellone when to replace the battery(eis).

http://flippers.com/esrkthnt.html (bottom of page)

Using the Bob Parker ESR (Blue - Anatek!) kit of course! Available from
us and others...

John :-#)#

--
(Please post followups or tech inquiries to the newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."

 

[PeterD]

I just replaced the battery in my UPS, and notice that the old one was
swollen and hard to remove. Searching this NG and elsewhere on the net, I
see this means that the battery had reached the end of its life some time
ago and should have been replaced sooner. Okay, replacing the battery
when it reaches the end of its life cycle instead of waiting until it
obviously fails is fine by me.

So how do I know when to replace a UPS battery? This particular UPS has
no self test feature and no com port with which to communicate with the
computer, and I don't want to toss perfectly working equipment into the
landfill just because it lacks bells and whistles to make my life a
little easier.

If nothing else, just use a two year schedule. A good UPS will
constantly evaluate the batteries and advise you when they are near
the end of their life. But that is only for the high end ones, not a
garden variety 500 to 1000 watt version.

A life test (such as the one suggested by the other poster, two 100
watt lamps (for a 400-500 watt unit) will work. You can compute how
long it should keep the lights on, and see what you get. Generally
when batteries get to the failure point, they discharge very quickly
(a couple of minutes max) instead of the expected 10 to 20 minutes a
UPS should provide.

 

[Jim Yanik]

Well, I'm seeking a way to identify when a battery needs to be replaced
*before* it fails the pull-the-plug test. By the time it reaches that
point, the battery has badly overheated and swollen. Surely I need to
have replaced the battery before that.

IMO,a weak battery will fail a pull-the-plug test(under load) well before
the batteries swell or crack open.

It just will not have a long run time.

 

[Rich Webb]

I just replaced the battery in my UPS, and notice that the old one was
swollen and hard to remove. Searching this NG and elsewhere on the net, I
see this means that the battery had reached the end of its life some time
ago and should have been replaced sooner. Okay, replacing the battery
when it reaches the end of its life cycle instead of waiting until it
obviously fails is fine by me.

So how do I know when to replace a UPS battery? This particular UPS has
no self test feature and no com port with which to communicate with the
computer, and I don't want to toss perfectly working equipment into the
landfill just because it lacks bells and whistles to make my life a
little easier.

Check the data sheet? I just had to replace the battery in my home setup
UPS and noticed that the datasheet for the replacement states "For main
and standby power supplies. Expected trickle life: 3-5 years at 25C,
Approx 5 years at 20C." (Panasonic LC-RA1212P)

Actual lifetime would depend on the quality of the trickle charge, how
often and for how long it's called upon to supply power, as well as how
hot it gets.

Absent a test circuit in the UPS, your best bet would be something like
a semi-annual load test, plotting the time-to-dropout versus lifetime.

 

[Warren Post]

It just will not have a long run time.

Ah, that's been my problem, then. I have never tested for longer than it
takes my system to shut down, which is only 60 seconds or so. Now that
I'm getting a new battery tomorrow, I'll measure the run time I get, and
again periodically.

Is there some rough guide as to when to replace the battery, such as (for
example) once run time has dropped to half?

For the benefit of lurkers reading this, you don't want to do the pull-
the-plug test while writable media are mounted. (Not while running
Windows, for example.) A Linux live CD (free for the download) would be a
safe choice for this.

 

[Warren Post]

I have several ways to test batteries. The easiest is to install one or
two 100 watt incandescent lamps into the UPS output, unplug the UPS from
AC power, and see how long it will run.

That's a better idea than my earlier suggestion of running the computer
with a live CD. I'll go with your idea.

"LearnByDestroying.com" -- that's a great domain name!

 

[Jim Yanik]

Ah, that's been my problem, then. I have never tested for longer than
it takes my system to shut down, which is only 60 seconds or so. Now
that I'm getting a new battery tomorrow, I'll measure the run time I
get, and again periodically.

Is there some rough guide as to when to replace the battery, such as
(for example) once run time has dropped to half?

half seems reasonable.
you know you're on the downside of the battery's life at that point!

 

[William Sommerwerck]

I just replaced the battery in my UPS, and notice that the

old one was swollen and hard to remove.

You, uh, weren't topping it off with a Viagra soulution, were you?

In all seriousness... You just wait until the battery won't take a charge,
then replace it. This means you might have to be without the SPS for a few
days.

 

[William Sommerwerck]

Well, I'm seeking a way to identify when a battery needs to be

replaced *before* it fails the pull-the-plug test. By the time it
reaches that point, the battery has badly overheated and swollen.

Not necessarily. The battery might conceivably have been damaged by a
problem with the SPS.

If you're worried about the same thing happening to the replacement, simply
open up the unit once a month. Most SPSs let you open them without
disconnecting anything. (The APCs do, anyway.)

 

[William Sommerwerck]

For the benefit of lurkers reading this, you don't want to do the pull-

the-plug test while writable media are mounted. (Not while running
Windows, for example.) A Linux live CD (free for the download)
would be a safe choice for this.

As long as nothing is being written to the media, this isn't a problem. I
can state as a fact that Windows 2000 will tolerate a cord yank without
damaging the operating system. (This is not true of all OSs.)

 

[Warren Post]

As long as nothing is being written to the media, this isn't a problem.
I can state as a fact that Windows 2000 will tolerate a cord yank
without damaging the operating system. (This is not true of all OSs.)

Actually, filesystem corruption is a subject I can address with more
authority than UPS batteries. I personally have seen and dealt with
several instances of filesystem corruption on Windows 2000 (and using the
more robust NTFS, not DOS) following a power failure when the box was
sitting idle.

A few caveats are in order:

Your condition is important and bears emphasis: "As long as nothing is
being written to the media". Good point. Recall, however, that all modern
filesystems improve performance by caching data and writing to the media
later during system idle times. This means that at any given moment a
filesystem may have dirty data, i.e. data cached that needs to be written
to the filesystem but hasn't been done yet.

To deal with (among other things) power failures that cause lost dirty
data and corruption, a journaling filesystem should normally be used.
Windows' default NTFS is journaling, and so it is indeed more robust than
its predecessor DOS in dealing with power failures. But perfect it ain't,
as I have repeatedly seen.

I haven't run any tests, but my unscientific observations lead me to
consider NTFS to be better than DOS but less robust than any other
journaled filesystem I am familiar with. So when I am setting up a
Windows box, I'll use NTFS, but only because Microsoft doesn't offer
anything better. If I'm setting up a Linux or other *nix box, I have a
choice, and I usually choose something bulletproof like XFS or EXT3.

Back to load testing UPS batteries. Jeff Lieberman successfully convinced
me elsewhere in this thread that incandescent lights make a far better
load than any computer running any OS. If for some hypothetical reason I
had to load test using a running box, it would be with no writable media
mounted, and as far as I know (correct me if I am wrong) that is not
possible with Windows. I will, however, cheerfully concede your point
that with Windows on NTFS you can *usually* get away with it.

 

[William Sommerwerck]

There's another point here... You should have the software configured so
that the computer shuts down fairly quickly after power is lost (within two
minutes or so). That will give you time to do it by hand if you're sitting
at the computer, while not (likely) running out of battery power before the
machine shuts itself down.

 

[1PW]

I just replaced the battery in my UPS, and notice that the old one was
swollen and hard to remove. Searching this NG and elsewhere on the net, I
see this means that the battery had reached the end of its life some time
ago and should have been replaced sooner. Okay, replacing the battery
when it reaches the end of its life cycle instead of waiting until it
obviously fails is fine by me.

So how do I know when to replace a UPS battery? This particular UPS has
no self test feature and no com port with which to communicate with the
computer, and I don't want to toss perfectly working equipment into the
landfill just because it lacks bells and whistles to make my life a
little easier.

Hello Warren:

In a previous life, I oversaw many systems with UPS protection. Some of
the UPS systems helped with super mission critical applications. As is
hinted in your post, your UPS(s) are not as fully featured as many are
today. You might wish to consider slowly moving your current UPS
system(s) to less critical applications while replacing them with higher
tech models. Some manufacturers had been offering a trade-up program at
one time.

Most manufacturers will offer a load chart to predict the rundown time
of a new/quality battery under various load conditions. While
maintaining some of my UPS systems, I obtained a short heavy-duty
extension cord and I stripped off the outer insulation covering to reach
the individual wires for ease of current measurements. I used various
combinations of output adjustable space heaters and heavy-duty soldering
irons to establish differing power testing loads. I found the
predictive charts rather accurate.

Some UPS manufacturers do seem to overcharge their batteries as has been
reported in other threads. This in combination with various repeated
full discharge cycles will limit the overall battery life of anything.
Where a UPS was lightly loaded and not driven to battery exhaustion more
than a few times, I'd see batteries last for five years. Less favorable
conditions gave us sometimes just three years. Worst case I saw was
about two years battery life.

Where a situation warranted it, I've mounted muffin fans directly to UPS
exhaust ports to improve air flow in rack mount configurations. Ugly
but effective.

Your reported observation would lead me to believe that your UPS is
overcharging its battery. I believe this is not easily dealt with and
probably not correctable without modifications.

HTH

Pete

 

[Bennett Price]

To prevent data corruption during a pull-the-AC-plug test, just
interrupt the bootup process so that you're sitting at a pre-Windows
screen. Or boot from a DOS floppy. All components will be consuming
power (though read/writes) take a bit more power) and you can accurately
gauge how much reserve time you've got. The problem with an
incandescent bulb test is that it is not your computer. Yes, it is
standardized, unlike the computer, but equating its results to computer
backup time is difficult.

 

[(PeteCresswell)]

Per 1PW:

In a previous life, I oversaw many systems with UPS protection.

Here's a question that's been in the back of my mind since I
found out that my APC unit uses a proprietary battery: How about
a UPS that uses a plain old non/vented automobile battery?

- Definitely non-proprietary.

- Probably has a lot more capacity than most consumer-level UPS's

- Quickly replaceable

- Probably cheaper, since it's a commodity

??

 

[1PW]

Per 1PW:

Here's a question that's been in the back of my mind since I
found out that my APC unit uses a proprietary battery: How about
a UPS that uses a plain old non/vented automobile battery?

- Definitely non-proprietary.

- Probably has a lot more capacity than most consumer-level UPS's

- Quickly replaceable

- Probably cheaper, since it's a commodity

??

Hello Pete:

We never had to try something like that. We only needed something to
absorb sudden dips and spikes. Our UPS systems just needed to last long
enough for our banks of big diesel driven generators to start, stabilize
and switch in.

However, your question is excellent. The problem lies in the design
differences of the batteries.

Typical thin plate automotive batteries will not withstand many deep
discharge cycles.

I believe the old adage that an automotive battery looses one year's
life for each deep discharge, is still mostly true. I believe that
sulphate damage begins with the very first deep discharge and would
accumulate with each additional deep discharge.

Industrial grade Sealed Lead Acid (SLA) batteries are constructed to
withstand these cycles with extra thick plates. This is not to say that
an automotive battery couldn't be used in a rare emergency, but to see
continued use would call for the proper industrial deep cycle type battery.

Someone may post a follow-up in this thread regarding the unmodified
UPS, sensing the automotive battery's soon dwindling voltage as an
unanticipated/early battery discharge.

I suppose you could look into using true/real marine/RV batteries, and
possibly modifying your UPS. However, UPS manufacturers are usually not
very forthcoming with their product's maintenance manuals, schematics,
piece parts, etc.

I encourage you to Google this for a deeper understanding.

My warm regards to you.

Pete

 

[PeterD]

Per 1PW:

Here's a question that's been in the back of my mind since I
found out that my APC unit uses a proprietary battery: How about
a UPS that uses a plain old non/vented automobile battery?

- Definitely non-proprietary.

- Probably has a lot more capacity than most consumer-level UPS's

- Quickly replaceable

- Probably cheaper, since it's a commodity

??

You would want a deep cycle battey... Which will not be cheap(er) but
whatever floats your boat so to speak!

I'd use something like an Optima (there are many similar brands). A
regular non-deep cycle battery *will* fail very quickly as they don't
like being fully discharged.

Check WalMart (if you're in the US) for deep-cycle batteries.
(Sometimes these are referred to marine batteries, but check
carefully!)