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Home > Archive > Alternative Power sources > October 2005 > UPS Batteries...The Good, The Bad and The Ugly
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| Author |
UPS Batteries...The Good, The Bad and The Ugly
|
|
| Too_Many_Tools 2005-10-19, 12:21 am |
| I just finished working on a number of UPSs.
One thing I noticed was that many of the Sealed Lead Acid (SLA)
batteries were swollen and hard to remove.
Why do SLA batteries swell?
I did notice that the UPS manufacturers apparently do not design for
this problem. Many of the UPSs had to be partially disassembled to
remove the batteries because of the tight quarters the battery
containers presented. Very poor design in my opinion.
Any suggestions for preventing a recurrence of this problem?
Thanks
TMT
| |
| Anthony Matonak 2005-10-19, 1:21 am |
| Too_Many_Tools wrote:
> I just finished working on a number of UPSs.
>
> One thing I noticed was that many of the Sealed Lead Acid (SLA)
> batteries were swollen and hard to remove.
>
> Why do SLA batteries swell?
It's part of their failure mode. Likely a combination of excess
gases at high pressure, high temperatures generated from shorted
plates and decomposing plates making themselves into funny shapes.
> I did notice that the UPS manufacturers apparently do not design for
> this problem. Many of the UPSs had to be partially disassembled to
> remove the batteries because of the tight quarters the battery
> containers presented. Very poor design in my opinion.
>
> Any suggestions for preventing a recurrence of this problem?
Sure, replace the batteries when they fail instead of waiting
a few years. 
Anthony
| |
| RoughRider 2005-10-19, 1:21 am |
| This is an economic situation in consumer devices where the commodity is
purchased, used, then chucked, never maintained, or fixed. UPS systems
along with much of todays electronics are cheap enough to make that they
become landfill at the moment something goes wrong. It can be cheaper to
buy a new laser printer (c/w toner cartridge) than to buy a replacement
toner cartridge. But I degress.
People want small, so no space is spared to allow for a bulging battery.
Mechanically, it is easier to fit the battery tight than to come up with a
different restraining method with space buffer (read: shave every penny off
that you can). Conversely, it is also about fitting the largest battery you
can into the available space.
The typical cheap gel cell UPS battery lasts about 5 years. There is also
heat in that UPS which doesn't make things easier. In commercial
applications, a battery is considered for replacement when it gets to 80% of
its original capacity (IEEE guideline). In the small UPS, people will
continue to use it until the load dies within seconds of a power failure,
well beyond battery end-of-life. With bad cells internally, the battery
created some additional heat during recharging.... which caused the battery
to accept more charge current.... more heat...more charge.... leading to
thermal runaway and the bulging plastic you see.
There are methods available to detect thermal runaway: Smart CPU
programming, temperature monitoring, etc... but it probably doesn't change
the fact that the manufacturer wants you to buy a completely new unit when
the battery fails. Or many consumers would do this anyway. You want a
cheap UPS, the temperature sensor gets removed along with some other frills.
For those that can switch the battery themselves, a new battery for a small
UPS costs between $12 and $30 wholesale depending on size.
The way they build things these days, next time you walk into a Walmart
store, consider where much of the goods will end up in 5 or so years!
| |
| Too_Many_Tools 2005-10-19, 2:21 am |
| Thanks for the responses so far....
When I say that there is no extra room in these UPSs, I mean not even
1/8" extra.
The UPSs were all commercial units that were being serviced per the
manufacturer's schedule.
TMT
| |
| George Ghio 2005-10-19, 3:21 am |
|
Too_Many_Tools wrote:
> I just finished working on a number of UPSs.
>
> One thing I noticed was that many of the Sealed Lead Acid (SLA)
> batteries were swollen and hard to remove.
>
> Why do SLA batteries swell?
The most common reason is exceeding the allowed charge voltage. Have
seen some that actually split their cases.
| |
| Too_Many_Tools 2005-10-19, 3:21 am |
| Some of the batteries that I removed had split...no acid leakage but
again I was surprised at the number and severity of the damage to the
batteries.
Shouldn't these batteries have vented before swelling and spliting?
Maybe what I am asking is are SLA batteries TOTALLY sealed? I would
expect a safety plug to vent before a rupture would occur.
TMT
| |
| Peter A Forbes 2005-10-19, 4:21 am |
| On 18 Oct 2005 22:32:46 -0700, "Too_Many_Tools" <too_many_tools@yahoo.com>
wrote:
>Some of the batteries that I removed had split...no acid leakage but
>again I was surprised at the number and severity of the damage to the
>batteries.
>
>Shouldn't these batteries have vented before swelling and spliting?
>
>Maybe what I am asking is are SLA batteries TOTALLY sealed? I would
>expect a safety plug to vent before a rupture would occur.
>
>TMT
Crystal growth between plates is the normal problem, related to sulphation,
which is caused by the batteries being overdischarged / left flat for long
periods.
Gas vents pop at quite low pressure, it is unlikely to be gas pressure.
Peter
--
Peter & Rita Forbes
Email: diesel@easynet.co.uk
Web: http://www.oldengine.org/members/diesel
| |
| George Ghio 2005-10-19, 5:21 am |
|
Too_Many_Tools wrote:
> Some of the batteries that I removed had split...no acid leakage but
> again I was surprised at the number and severity of the damage to the
> batteries.
>
> Shouldn't these batteries have vented before swelling and spliting?
They probably did. That's part of the trouble, anything lost cannot be
replaced. But the charger keeps charging.
>
> Maybe what I am asking is are SLA batteries TOTALLY sealed? I would
> expect a safety plug to vent before a rupture would occur.
No safety plug.
>
> TMT
>
| |
| Vaughn 2005-10-19, 8:21 am |
|
"Too_Many_Tools" <too_many_tools@yahoo.com> wrote in message
news:1129690971.151682.228850@f14g2000cwb.googlegroups.com...
>
> I did notice that the UPS manufacturers apparently do not design for
> this problem. Many of the UPSs had to be partially disassembled to
> remove the batteries because of the tight quarters the battery
> containers presented. Very poor design in my opinion.
(excessive x-posting removed)
I have come to the conclusion that your average consumer UPS has a terrible
charging circuit. (At this point, this can only be classed as a deep suspicion
because actual circuit information on these units seems to be unobtainable.)
It is a true shame, because a few cents worth of components could double
the life of the unit and make it considerably more efficient.
Vaughn
| |
| George Ghio 2005-10-19, 9:21 am |
|
Peter A Forbes wrote:
> On 18 Oct 2005 22:32:46 -0700, "Too_Many_Tools" <too_many_tools@yahoo.com>
> wrote:
>
>
>
>
> Crystal growth between plates is the normal problem, related to sulphation,
> which is caused by the batteries being overdischarged / left flat for long
> periods.
>
> Gas vents pop at quite low pressure, it is unlikely to be gas pressure.
>
> Peter
> --
> Peter & Rita Forbes
> Email: diesel@easynet.co.uk
> Web: http://www.oldengine.org/members/diesel
Yep, over charge the suckers and you lose material. It can't be put
back, battery degrades, fails. Seen it often.
| |
| Steve Spence 2005-10-19, 11:21 am |
| Too_Many_Tools wrote:
> I just finished working on a number of UPSs.
>
> One thing I noticed was that many of the Sealed Lead Acid (SLA)
> batteries were swollen and hard to remove.
>
> Why do SLA batteries swell?
>
> I did notice that the UPS manufacturers apparently do not design for
> this problem. Many of the UPSs had to be partially disassembled to
> remove the batteries because of the tight quarters the battery
> containers presented. Very poor design in my opinion.
>
> Any suggestions for preventing a recurrence of this problem?
>
> Thanks
>
> TMT
>
overheating, over charging. we had the ac fail in our data center over
the weekend, and the telephone tattletale failed to call out. Room temp
was 150F when we showed up for work on monday. batteries burst, acid on
the floor, backup tapes destroyed by heat and acid fumes, servers dead,
etc ......
--
Steve Spence
Dir., Green Trust, http://www.green-trust.org
Contributing Editor, http://www.off-grid.net
http://www.rebelwolf.com/essn.html
| |
| Too_Many_Tools 2005-10-19, 11:21 am |
| Ouch....my condolences to whoever had to clean that mess up..
TMT
| |
| Steve Spence 2005-10-19, 11:21 am |
| Too_Many_Tools wrote:
> Ouch....my condolences to whoever had to clean that mess up..
>
> TMT
>
Thanks. The CTO and Dir. of IT were conspiciously absent .....
It was left up to us net engineers and a couple of admins.
we flushed the floor with lots of water to neutralize the acid, did lots
of moping, and wiping, and cdw was happy to take our orders for
replacements.
--
Steve Spence
Dir., Green Trust, http://www.green-trust.org
Contributing Editor, http://www.off-grid.net
http://www.rebelwolf.com/essn.html
| |
| Too_Many_Tools 2005-10-19, 11:21 am |
| "I have come to the conclusion that your average consumer UPS has a
terrible
charging circuit. (At this point, this can only be classed as a deep
suspicion
because actual circuit information on these units seems to be
unobtainable.)
It is a true shame, because a few cents worth of components could
double
the life of the unit and make it considerably more efficient. "
I would agree with you from what I have seen. As others have pointed
out, I think the design criteria is for building a CHEAP unit and to
coerce the buyer into buying the next UPS as soon as possible.
When I examined the UPSs, it was evident that pennies were saved by the
manufacturer that cost the user money later which included the unit
replacement.
Perhaps UPSs need to be rated for longevity...instead of initial cost
and runtime?
I also am thinking that an auxillary circuit could be placed between
the UPS and the batteries to monitor and prevent overcharging?
TMT
| |
| nospam@nouce.bellatlantic.net 2005-10-19, 12:21 pm |
| On 18 Oct 2005 20:02:51 -0700, "Too_Many_Tools"
<too_many_tools@yahoo.com> wrote:
>I just finished working on a number of UPSs.
>
>One thing I noticed was that many of the Sealed Lead Acid (SLA)
>batteries were swollen and hard to remove.
>
>Why do SLA batteries swell?
>
>I did notice that the UPS manufacturers apparently do not design for
>this problem. Many of the UPSs had to be partially disassembled to
>remove the batteries because of the tight quarters the battery
>containers presented. Very poor design in my opinion.
>
>Any suggestions for preventing a recurrence of this problem?
>
>Thanks
>
>TMT
Personal experience with APC UPSs in the 500VA to 1400 VA range is
they charge hard and selftest too often. The latter was really bad
for the batteries. As recieved and installed with they will self
test every two weeks, Selftest runs the batteries well down the
curve and failure was often around 13months. Extended selftest to
every 4 weeks and the batteries were still solid at 25 months at
which point they were replaced with new for reliability reasons. The
old batteries were still 80% good or better likely due to the fewer
number of discharge and hard charge cycles.
Another thing that will kill batteries fast is using the UPS to run
the system or printer till exhaustion. I tried it to see what happens
and the usual 7a gell cell in a 300VA unit expired after 20 cycles
of that. Lesson, it's momentary backup, not aux power.
UPSs fall into two classes from what I see. Those big enough to
bridge many hours of power failure (really big batts and lightly
loaded) and those really intended to allow enough time to do a quick
finish and shutdown or bridge those annoying under 1 minute outages
and severe but momentary line voltage fluctuations. Most of those
consumer units sold are for the latter and really work well for that.
Allison
| |
| Ecnerwal 2005-10-19, 1:21 pm |
| In article <KRr5f.30024$Ge5.20432@fe10.lga>,
Steve Spence <sspence@green-trust.org> wrote:
> overheating, over charging. we had the ac fail in our data center over
> the weekend, and the telephone tattletale failed to call out. Room temp
> was 150F when we showed up for work on monday. batteries burst, acid on
> the floor, backup tapes destroyed by heat and acid fumes, servers dead,
> etc ......
Bad design. Batteries, computers and tapes all in the same room? Common,
but not good design. Any offsite backups? Servers and their on-site
backup tapes should be separated by enough distance that a minor fire
won't get both, and fully offsite backups should be far enough away that
major fire, flood, tornado, etc won't get both (unless it's a tornado
with a flight plan to make your life miserable). A serious computer
center UPS should be down in some nice isolated basement room...
--
Cats, coffee, chocolate...vices to live by
| |
| danny burstein 2005-10-19, 1:21 pm |
| In <LawrenceSMITH-C162AA.11573419102005@news.verizon.net> Ecnerwal <LawrenceSMITH@SOuthernVERmont.NyET> writes:
[ snip ]
>with a flight plan to make your life miserable). A serious computer
>center UPS should be down in some nice isolated basement room...
err, you're much better off with it
above any flood level...
which reminds me of what may, or may not, be a true
story back during the 1965 blackout.
(like all good urban legends, there's enough
plausability here, but I've been unable
to directly verify it).
In the Good Old Days before all the blackouts,
(and before modern day computers and such)
emergency power and lighting was in very few places.
One place usually equipped with something or another
was the local hospital.
NYC had (and has...) a very large municipal
facility called Bellevue. Well known (no) thanks
to generations of tv and movies as a psych place,
it's actually a fully capable (and nowadays
very highly regarded) institution.
Anyway, back in 1965 it had, by 1965 standards,
a pretty good emergency generator setup.
(In fact, in the early 1970s I saw the physical
power plant which had been installed Way Back When
We Built Things Right).
So... when the Sir Adam Beck substation did
its thing and plunged the northeast US (including NYC)
into darkness in 1965, Bellevue went out as well. But
a few minutes later, the generators came on and things
were back to (by 1965 standards) normal.
Except for one little problem.
Generators, especially back then, were big and ugly
and heavy. So... would be in a basement. (Additional
reason for this is it made getting the fuel to them
quite a bit simpler and more reliable).
ok... you know where I'm going...
Guess how high above sea level Bellevue is...
That's right, it's only a couple of dozen feet.
Now guess how high above sea level the
sub, sub, basement... where the generators
were located... is.
Eyup.
Now guess what critical part of the Bellevue plant
was _not_ hooked up to emergency power?
Eyup... the sump pumps.
So a couple of hours after the power went out,
the generators were underwater.
The end.
--
_____________________________________________________
Knowledge may be power, but communications is the key
dannyb@panix.com
[to foil spammers, my address has been double rot-13 encoded]
| |
| Steve Spence 2005-10-19, 2:21 pm |
| Ecnerwal wrote:
> In article <KRr5f.30024$Ge5.20432@fe10.lga>,
> Steve Spence <sspence@green-trust.org> wrote:
>
>
>
>
> Bad design. Batteries, computers and tapes all in the same room? Common,
> but not good design. Any offsite backups? Servers and their on-site
> backup tapes should be separated by enough distance that a minor fire
> won't get both, and fully offsite backups should be far enough away that
> major fire, flood, tornado, etc won't get both (unless it's a tornado
> with a flight plan to make your life miserable). A serious computer
> center UPS should be down in some nice isolated basement room...
>
The tapes were in the backup drives. 7 tape dlt loaders. These were
current tapes, not storage. no seperate liebert unit, these were
rackmounted apc units in the same racks as the servers. This company
wasn't serious about anything except the ceo's morning plate of carrots
......
--
Steve Spence
Dir., Green Trust, http://www.green-trust.org
Contributing Editor, http://www.off-grid.net
http://www.rebelwolf.com/essn.html
| |
| Windsun 2005-10-19, 2:21 pm |
| A few years ago we did a check on a bunch of UPS systems installed locally
for computer backup in some local city and company offices - about 30 total.
Of those, about 1/2 had batteries good enough to even fire up the UPS, and
about 1/2 of those that did were very marginal, such as only having enough
capacity for 10 minutes instead of the rated 30 minutes or so.
Going by that, I would bet that nearly half of the UPS systems in the
country don't work.
-------------------------------------------------------------------------
Free Solar Discussion Forum: http://www.wind-sun.com/smf/index.php
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"Anthony Matonak" <anthonym40@nothing.like.comcast.net> wrote in message
news:6c2dnX8Fr7mnWcjenZ2dnUVZ_tOdnZ2d@comcast.com...
> Sure, replace the batteries when they fail instead of waiting
> a few years.
>
> Anthony
| |
|
| In article <uus5f.30032$Ge5.21918@fe10.lga>,
Steve Spence <sspence@green-trust.org> wrote:
> Too_Many_Tools wrote:
> Thanks. The CTO and Dir. of IT were conspiciously absent .....
>
> It was left up to us net engineers and a couple of admins.
>
> we flushed the floor with lots of water to neutralize the acid, did lots
> of moping, and wiping, and cdw was happy to take our orders for
> replacements.
Should have dumped a couple of boxes of Arm & Hammer Baking Soda
in the water before you flushed the floor, and moped it up.......
Me
| |
| LawsonHuntley@aol.com 2005-10-19, 6:21 pm |
|
Too_Many_Tools wrote:[color=darkred]
You've already got a lot of good replys in regard to the swelling of
the plastic cases being due to higher than normal temperatures and
pressures; and even much higher, such as happens in thermal runaway.
In addition, as the batteries age and lose capacity, a portion of the
active materials in both the anode and cathode are slowly forming
molecules of lead sulfate that are not being reversed in the charging
process. The lead sulfate molecule may become tribasic in nature, or
even tetrabasic (at higher temperatures), either of which is a larger
molecule than the original active material.
Even flooded cells in tight confinement will swell enough to become
very difficult to remove.
| |
| Steve Thomas 2005-10-19, 6:21 pm |
| Baking soda can be dangerous if there is any significant quantity of acid.
We had a material handling accident with a full pallet of new car
batteries once. A large sack of sodium bicarbonate was on hand for the
purpose of neutralizing small spills. Several pounds were dumped on the
resulting pool of acid. That was a big mistake. The fizzing release of CO2
in the pool of acid created an aerosol cloud of corrosive, choking, stinging
acid mist. It was not an experience I would care to repeat, and it was not
popular with the other people working in the area.
Based on this experience, we concluded that baking soda should only be
used to neutralize what remains after the primary cleanup has been
completed, or for very small spills.
"Me" <Me@shadow.orgs> wrote in message
news:Me-2DCF11.10271219102005@netnews.worldnet.att.net...
> In article <uus5f.30032$Ge5.21918@fe10.lga>,
> Steve Spence <sspence@green-trust.org> wrote:
>
>
> Should have dumped a couple of boxes of Arm & Hammer Baking Soda
> in the water before you flushed the floor, and moped it up.......
>
> Me
| |
| Too_Many_Tools 2005-10-19, 7:21 pm |
| "The CTO and Dir. of IT were conspiciously absent ..... "
They are always are when there is work to do.
TMT
| |
| Too_Many_Tools 2005-10-19, 7:21 pm |
| "This company wasn't serious about anything except the ceo's morning
plate of carrots "
Funny....wish I had come up with that comment.
TMT
| |
| Too_Many_Tools 2005-10-19, 7:21 pm |
| Good comments...
If cells will swell and it is a known condition, then why do UPS
manufactures not allow for it in their battery case designs?
It would seem to be a common complaint from users and you would think
sooner or later the products would have space dedicated to this
condition.
TMT
| |
| Ian Stirling 2005-10-19, 8:21 pm |
| In sci.chem.electrochem.battery Too_Many_Tools <too_many_tools@yahoo.com> wrote:
> Good comments...
>
> If cells will swell and it is a known condition, then why do UPS
> manufactures not allow for it in their battery case designs?
>
> It would seem to be a common complaint from users and you would think
> sooner or later the products would have space dedicated to this
> condition.
You think that they want you to replace the batteries?
| |
| Steve Spence 2005-10-19, 8:21 pm |
| Too_Many_Tools wrote:
> "This company wasn't serious about anything except the ceo's morning
> plate of carrots "
>
> Funny....wish I had come up with that comment.
>
> TMT
>
You had to be there, listening to him stop down the halls yelling
"Where's my damn carrots, I want my carrots ....."
--
Steve Spence
Dir., Green Trust, http://www.green-trust.org
Contributing Editor, http://www.off-grid.net
http://www.rebelwolf.com/essn.html
| |
| Solar Flare 2005-10-19, 9:21 pm |
| Similar case. We had our emerg generator rewired and when the power went out in
the Ontario blackout from the Ohio faults the ventilation flaps to the generator
room were on insecure power and the generator would overheat.
Small oversights people miss until D day.
"danny burstein" <dannyb@panix.com> wrote in message
news:dj5ras$b6h$1@reader2.panix.com...
> In <LawrenceSMITH-C162AA.11573419102005@news.verizon.net> Ecnerwal
<LawrenceSMITH@SOuthernVERmont.NyET> writes:
>
> [ snip ]
>
>
>
> err, you're much better off with it
> above any flood level...
>
> which reminds me of what may, or may not, be a true
> story back during the 1965 blackout.
>
> (like all good urban legends, there's enough
> plausability here, but I've been unable
> to directly verify it).
>
> In the Good Old Days before all the blackouts,
> (and before modern day computers and such)
> emergency power and lighting was in very few places.
>
> One place usually equipped with something or another
> was the local hospital.
>
> NYC had (and has...) a very large municipal
> facility called Bellevue. Well known (no) thanks
> to generations of tv and movies as a psych place,
> it's actually a fully capable (and nowadays
> very highly regarded) institution.
>
> Anyway, back in 1965 it had, by 1965 standards,
> a pretty good emergency generator setup.
>
> (In fact, in the early 1970s I saw the physical
> power plant which had been installed Way Back When
> We Built Things Right).
>
> So... when the Sir Adam Beck substation did
> its thing and plunged the northeast US (including NYC)
> into darkness in 1965, Bellevue went out as well. But
> a few minutes later, the generators came on and things
> were back to (by 1965 standards) normal.
>
> Except for one little problem.
>
> Generators, especially back then, were big and ugly
> and heavy. So... would be in a basement. (Additional
> reason for this is it made getting the fuel to them
> quite a bit simpler and more reliable).
>
> ok... you know where I'm going...
>
> Guess how high above sea level Bellevue is...
>
> That's right, it's only a couple of dozen feet.
>
> Now guess how high above sea level the
> sub, sub, basement... where the generators
> were located... is.
>
> Eyup.
>
> Now guess what critical part of the Bellevue plant
> was _not_ hooked up to emergency power?
>
> Eyup... the sump pumps.
>
> So a couple of hours after the power went out,
> the generators were underwater.
>
> The end.
> --
> _____________________________________________________
> Knowledge may be power, but communications is the key
> dannyb@panix.com
> [to foil spammers, my address has been double rot-13 encoded]
| |
| Robert Morein 2005-10-19, 9:21 pm |
|
"Too_Many_Tools" <too_many_tools@yahoo.com> wrote in message
news:1129759207.817079.267810@g44g2000cwa.googlegroups.com...
> Good comments...
>
> If cells will swell and it is a known condition, then why do UPS
> manufactures not allow for it in their battery case designs?
>
> It would seem to be a common complaint from users and you would think
> sooner or later the products would have space dedicated to this
> condition.
>
> TMT
>
My guess: shock damage during shipping and handling would be higher if the
batteries fit loosely.
If they put in padding, they have to think about durability and resistance
to fire. Also, any insulating material would increase the chance the
batteries would go into thermal runaway.
I have a rack of Hawker Powersafe VM1500 cells. These way about 3000 lbs.
The cells fit very snugly into the rack. Apparently, the cell case itself is
not strong enough, by itself, for extended use. Cost was not a consideration
in this design.
| |
| Warren Weber 2005-10-19, 9:21 pm |
|
"Too_Many_Tools" <too_many_tools@yahoo.com> wrote in message
news:1129690971.151682.228850@f14g2000cwb.googlegroups.com...
>I just finished working on a number of UPSs.
>
> One thing I noticed was that many of the Sealed Lead Acid (SLA)
> batteries were swollen and hard to remove.
>
> Why do SLA batteries swell?
>
> I did notice that the UPS manufacturers apparently do not design for
> this problem. Many of the UPSs had to be partially disassembled to
> remove the batteries because of the tight quarters the battery
> containers presented. Very poor design in my opinion.
>
> Any suggestions for preventing a recurrence of this problem?
>
> Thanks
>
> TMT
I just had 2 Tripp Lite UPS fail the same way. Charging voltage was 17.5
volts. I e mailed Tripp Lite and asked for a schematic so I could tweak the
charging voltage down. They would not reply so I replaced with UPC brand. I
hope these are better designed. WW
| |
| Ecnerwal 2005-10-19, 11:21 pm |
| In article <1129690971.151682.228850@f14g2000cwb.googlegroups.com>,
"Too_Many_Tools" <too_many_tools@yahoo.com> wrote:
> I just finished working on a number of UPSs.
>
> One thing I noticed was that many of the Sealed Lead Acid (SLA)
> batteries were swollen and hard to remove.
>
> Why do SLA batteries swell?
Sulfation, mostly. Crystal growth pries the plates apart.
> I did notice that the UPS manufacturers apparently do not design for
> this problem.
Yes, they did. They designed for you to have this problem (tight case,
overcharge batteries as a matter of course), so that you would buy
another hunk of junk UPS in a few short years. They are delighted that
you are having this problem, but wish you would not waste your valuable
time prying out stuck batteries, when you could just buy a new, cheap
UPS...
> Any suggestions for preventing a recurrence of this problem?
Sure - Buy an Outback inverter/charger and set up a battery bank (in a
large battery box, with space for them). Hang solar panels off of it, or
don't, as you prefer (works either way, cheaper without). Tain't cheap,
but it ain't inherently defective from the get-go (as most UPSs are),
either.
Some of the Trace stuff will work, cheaper, but the brains that made
Trace good are now at Outback, and (most, but not all) reports are that
the current management at Trace (aka Xantrex, aka the borg-like-company
that bought out most of the other inverter companies) is less than
delightful to deal with. Outback appears to be quite delightful to deal
with, and constantly improving things.
Not even a customer yet, but expect to be soon.
--
Cats, coffee, chocolate...vices to live by
| |
| nospam.clare.nce@sny.der.on.ca 2005-10-20, 12:21 am |
| On Wed, 19 Oct 2005 18:02:30 -0600, "Warren Weber" <hiview68NO
SPAM@1236bresnan.net> wrote:
>
>I just had 2 Tripp Lite UPS fail the same way. Charging voltage was 17.5
>volts. I e mailed Tripp Lite and asked for a schematic so I could tweak the
>charging voltage down. They would not reply so I replaced with UPC brand. I
>hope these are better designed. WW
>
In your dreams. They are just about as chintily designed and built as
TrippLite and the old Minuteman. Anywhere they can save a penny per
unit, they make a dollar per hundred
| |
|
| In article <FIGdnYEbr88bQ8veRVn-sw@bresnan.com>,
"Warren Weber" <hiview68NO SPAM@1236bresnan.net> wrote:
> "Too_Many_Tools" <too_many_tools@yahoo.com> wrote in message
> news:1129690971.151682.228850@f14g2000cwb.googlegroups.com...
>
> I just had 2 Tripp Lite UPS fail the same way. Charging voltage was 17.5
> volts. I e mailed Tripp Lite and asked for a schematic so I could tweak the
> charging voltage down. They would not reply so I replaced with UPC brand. I
> hope these are better designed. WW
>
>
Tripp Lite has always been very BAD for supporting theeir stuff.....
don't expect to get any help from them.....
Me
| |
| Pete C 2005-10-20, 8:21 pm |
| On 19 Oct 2005 07:14:40 -0700, "Too_Many_Tools"
<too_many_tools@yahoo.com> wrote:
>"I have come to the conclusion that your average consumer UPS has a
>terrible
>charging circuit. (At this point, this can only be classed as a deep
>suspicion
>because actual circuit information on these units seems to be
>unobtainable.)
>
> It is a true shame, because a few cents worth of components could
>double
>the life of the unit and make it considerably more efficient. "
>
>I would agree with you from what I have seen. As others have pointed
>out, I think the design criteria is for building a CHEAP unit and to
>coerce the buyer into buying the next UPS as soon as possible.
>
>When I examined the UPSs, it was evident that pennies were saved by the
>manufacturer that cost the user money later which included the unit
>replacement.
>
>Perhaps UPSs need to be rated for longevity...instead of initial cost
>and runtime?
>
>I also am thinking that an auxillary circuit could be placed between
>the UPS and the batteries to monitor and prevent overcharging?
Hi,
Just put a chunky diode between UPS and battery to block charge
current to the battery from the UPS, but allow current from the
battery on mains failure. Then use a normal SLA charger on the UPS
battery.
Or use a diode as above and a string of smaller diodes the other way
to drop the charge voltage down to a sensible level.
cheers,
Pete.
| |
|
| "Windsun" <wind-sun@earthlink.net> wrote in
news:N0v5f.2795$fc7.35@newsread3.news.pas.earthlink.net:
> A few years ago we did a check on a bunch of UPS systems
> installed locally for computer backup in some local city and
> company offices - about 30 total.
>
> Of those, about 1/2 had batteries good enough to even fire up
> the UPS, and about 1/2 of those that did were very marginal,
> such as only having enough capacity for 10 minutes instead of
> the rated 30 minutes or so.
>
> Going by that, I would bet that nearly half of the UPS systems
> in the country don't work.
>
Back a few years ago when I was doing this kind of thing for a
living the group I was working with had standardized on APC UPSs
for several reasons. One was the on-board self testing that could
be scheduled on a periodic basis where the system would actually
switch to battery and measure how long it took to consume 10% of
it's charge, and report that to the computer monitoring all the
UPSs. Made it handy to check the battery status, etc.
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