UPS battery replacement

[JK]

I had to do an emergency replacement last weekend. The bad
battery was:

12vdc, 4 amp hour gell cell

All I could find locally was:

12vdc, 5 amp hour gell cell


The batteries are identical except for the amp hour ratings.

I don't *think* moving up an amp hour should be a problem with this
type of battery. Am I right?

Thanks for your time.

--
..

 

[Dave Platt]

I had to do an emergency replacement last weekend. The bad
battery was:

12vdc, 4 amp hour gell cell

All I could find locally was:

12vdc, 5 amp hour gell cell


The batteries are identical except for the amp hour ratings.

I don't *think* moving up an amp hour should be a problem with this
type of battery. Am I right?

Very probably. It is *possible* that the new battery may have
slightly different charging requirements than the old one, if you want
to get the maximum service life out of it, but that's by no means
certain. Aside from that, the two should be compatible.

--
Dave Platt <dplatt@radagast.org> AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

 

[Phil Hobbs]

On 10/09/2012 03:50 PM, Dave Platt wrote:

I had to do an emergency replacement last weekend. The bad
battery was:

12vdc, 4 amp hour gell cell

All I could find locally was:

12vdc, 5 amp hour gell cell


The batteries are identical except for the amp hour ratings.

I don't *think* moving up an amp hour should be a problem with this
type of battery. Am I right?

Very probably. It is *possible* that the new battery may have
slightly different charging requirements than the old one, if you want
to get the maximum service life out of it, but that's by no means
certain. Aside from that, the two should be compatible.

Watch out for gel cells that aren't rated for SMPS service. Those
suckers get drawn down _fast_, and lots of the cheaper ones won't
survive. (Ask me how I know.)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

 

On Tuesday, October 9, 2012 12:30:36 PM UTC-7, JK wrote:

I had to do an emergency replacement last weekend. The bad
battery was: 12vdc, 4 amp hour gell cell All I could find
locally was: 12vdc, 5 amp hour gell cell The batteries are
identical except for the amp hour ratings. I don't *think*
moving up an amp hour should be a problem with this type of
battery. Am I right?

An increase like that won't hurt, except to need 25% more time to fully charge the battery, and notice that older backup supplies fully charge in 8-12 hours, while newer ones need up to twice that time (seems to make batteries last longer). IOW even a much lower charging current won't hurt, and it's only when you switch to a far larger battery that current can become too low (car batteries are rated for 60 amp hours).

 

[Paul Drahn]

On 10/9/2012 12:30 PM, JK wrote:

I had to do an emergency replacement last weekend. The bad
battery was:

12vdc, 4 amp hour gell cell

All I could find locally was:

12vdc, 5 amp hour gell cell


The batteries are identical except for the amp hour ratings.

I don't *think* moving up an amp hour should be a problem with this
type of battery. Am I right?

Thanks for your time.

--
.

It they are the same size, the rating is just a marketing ploy!

Paul

 

[mike]

On 10/9/2012 1:02 PM, Phil Hobbs wrote:

On 10/09/2012 03:50 PM, Dave Platt wrote:
I had to do an emergency replacement last weekend. The bad
battery was:

12vdc, 4 amp hour gell cell

All I could find locally was:

12vdc, 5 amp hour gell cell


The batteries are identical except for the amp hour ratings.

I don't *think* moving up an amp hour should be a problem with this
type of battery. Am I right?

Very probably. It is *possible* that the new battery may have
slightly different charging requirements than the old one, if you want
to get the maximum service life out of it, but that's by no means
certain. Aside from that, the two should be compatible.


Watch out for gel cells that aren't rated for SMPS service. Those
suckers get drawn down _fast_, and lots of the cheaper ones won't
survive. (Ask me how I know.)

Cheers

Phil Hobbs

I've had that same question. I get that cheapo batteries are typically

lower quality. But how do you tell that an expensive battery isn't just
a cheapo battery with a higher price tag? They all seem to have the same
specs.
Any advice on brands?

 

[who where]

On Tue, 09 Oct 12 15:30:15 EDT, JK <nomail@mail.invalid> wrote:

I had to do an emergency replacement last weekend. The bad
battery was:

12vdc, 4 amp hour gell cell

All I could find locally was:

12vdc, 5 amp hour gell cell


The batteries are identical except for the amp hour ratings.

I don't *think* moving up an amp hour should be a problem with this
type of battery. Am I right?

Not a problem as such, but you need to ensure that the replacement(s)
are suitable for UPS duty and not just GP types.

 

[William Sommerwerck]

Any advice on brands?

I've bought lead-acid batteries for several products (lantern, audio
analyzer, alarm system), and have been happy with CS3 batteries. My alarm
system uses Power Sonic, but I don't know what that proves.

 

[Jeff Liebermann]

On Tue, 09 Oct 2012 16:02:42 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

On 10/09/2012 03:50 PM, Dave Platt wrote:
I had to do an emergency replacement last weekend. The bad
battery was:
12vdc, 4 amp hour gell cell
All I could find locally was:
12vdc, 5 amp hour gell cell
The batteries are identical except for the amp hour ratings.

I don't *think* moving up an amp hour should be a problem with this
type of battery. Am I right?

Very probably. It is *possible* that the new battery may have
slightly different charging requirements than the old one, if you want
to get the maximum service life out of it, but that's by no means
certain. Aside from that, the two should be compatible.

Watch out for gel cells that aren't rated for SMPS service. Those
suckers get drawn down _fast_, and lots of the cheaper ones won't
survive. (Ask me how I know.)
Phil Hobbs

I've found that the quality and survivability of gel cells can be
estimated by their weight. Light weight batteries don't have enough
lead and will die an early death. The differences are fairly subtle
for small 50A-hr gel cells, but become obvious with the bigger
batteries.
<http://groups.google.com/group/sci.electronics.repair/msg/d2e2cb9eb130b695>

I don't know what constitutes a SMPS (UPS) rated gel cell. Most of
the batteries I buy claim that the battery can be used in everything
from electric toy cars to USP's with little distinction as to type of
service. What I've found is that many UPS's over charge their
batteries. Measure the charge current at various discharge levels and
I suspect you'll find that many UPS's are trying to squeeze the last
bit of power out of their batteries in order to give longer runtime.
They also tend to recharge rather quickly, in order to deal with
repetitive power failures.

I had a running battle with APC over this issue on some of their
products. Note the pile of rack mounted (forgot the model number) APC
UPS's piled up on my deck:
<http://802.11junk.com/jeffl/pics/home/slides/BL-house3.html>
There were many many more that were ummm... recycled because the
batteries got hot, bulged, and eventually leaked electrolyte all over
the equipment. This UPS used four 12V 7A gel cells in a 24V
series/parallel combination.


--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Jeff Liebermann]

On Tue, 09 Oct 2012 17:20:09 -0700, mike <spamme9@gmail.com> wrote:

I've had that same question. I get that cheapo batteries are typically
lower quality. But how do you tell that an expensive battery isn't just
a cheapo battery with a higher price tag? They all seem to have the same
specs.

Weight. Heavier is better. See my previous rant in this thread.
Also, the length of the battery warranty is an important clue.

Any advice on brands?

PowerSonic, Yuasa are what I like and use. The local Batteries Plus
store sells Werker, with which I've seen a few short lifetime
problems. I've been experimenting with random AGM battery
replacements, with good results so far.



--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Phil Hobbs]

On 10/09/2012 08:20 PM, mike wrote:

On 10/9/2012 1:02 PM, Phil Hobbs wrote:
On 10/09/2012 03:50 PM, Dave Platt wrote:
I had to do an emergency replacement last weekend. The bad
battery was:

12vdc, 4 amp hour gell cell

All I could find locally was:

12vdc, 5 amp hour gell cell


The batteries are identical except for the amp hour ratings.

I don't *think* moving up an amp hour should be a problem with this
type of battery. Am I right?

Very probably. It is *possible* that the new battery may have
slightly different charging requirements than the old one, if you want
to get the maximum service life out of it, but that's by no means
certain. Aside from that, the two should be compatible.


Watch out for gel cells that aren't rated for SMPS service. Those
suckers get drawn down _fast_, and lots of the cheaper ones won't
survive. (Ask me how I know.)

Cheers

Phil Hobbs

I've had that same question. I get that cheapo batteries are typically
lower quality. But how do you tell that an expensive battery isn't just
a cheapo battery with a higher price tag? They all seem to have the same
specs.
Any advice on brands?

I've had good luck with the on-shore and European brands, e.g. Varta.
IME usually there's a sticker inside the unit or a table in the manual
that gives recommended battery types.

I tend to buy used IBM e-server UPSes, which are rebranded APC SmartUPS
units, and seem to go much cheaper than the APC-branded ones. I've got
three 750 VA ones for $50 each, so even with a $60 battery it's still
pretty affordable. (The supplies themselves seem pretty bulletproof.)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

 

[mike]

On 10/10/2012 9:48 AM, Phil Hobbs wrote:

On 10/09/2012 08:20 PM, mike wrote:
On 10/9/2012 1:02 PM, Phil Hobbs wrote:
On 10/09/2012 03:50 PM, Dave Platt wrote:
I had to do an emergency replacement last weekend. The bad
battery was:

12vdc, 4 amp hour gell cell

All I could find locally was:

12vdc, 5 amp hour gell cell


The batteries are identical except for the amp hour ratings.

I don't *think* moving up an amp hour should be a problem with this
type of battery. Am I right?

Very probably. It is *possible* that the new battery may have
slightly different charging requirements than the old one, if you want
to get the maximum service life out of it, but that's by no means
certain. Aside from that, the two should be compatible.


Watch out for gel cells that aren't rated for SMPS service. Those
suckers get drawn down _fast_, and lots of the cheaper ones won't
survive. (Ask me how I know.)

Cheers

Phil Hobbs

I've had that same question. I get that cheapo batteries are typically
lower quality. But how do you tell that an expensive battery isn't just
a cheapo battery with a higher price tag? They all seem to have the same
specs.
Any advice on brands?

I've had good luck with the on-shore and European brands, e.g. Varta.
IME usually there's a sticker inside the unit or a table in the manual
that gives recommended battery types.

I tend to buy used IBM e-server UPSes, which are rebranded APC SmartUPS
units, and seem to go much cheaper than the APC-branded ones. I've got
three 750 VA ones for $50 each, so even with a $60 battery it's still
pretty affordable. (The supplies themselves seem pretty bulletproof.)

Cheers

Phil Hobbs

I buy my UPSes at garage sales. They're the cheapo consumer toys that went

dead and were left in the garage a few more years. Batteries are always
toast.
Power around here rarely goes out for more than a second. If it's out
longer than that, it's probably gonna be out for longer than an affordable
UPS could handle. Current system is down to about a minute run time.
Should replace the battery.

 

[Phil Hobbs]

On 10/10/2012 03:45 PM, mike wrote:

On 10/10/2012 9:48 AM, Phil Hobbs wrote:
On 10/09/2012 08:20 PM, mike wrote:
On 10/9/2012 1:02 PM, Phil Hobbs wrote:
On 10/09/2012 03:50 PM, Dave Platt wrote:
I had to do an emergency replacement last weekend. The bad
battery was:

12vdc, 4 amp hour gell cell

All I could find locally was:

12vdc, 5 amp hour gell cell


The batteries are identical except for the amp hour ratings.

I don't *think* moving up an amp hour should be a problem with this
type of battery. Am I right?

Very probably. It is *possible* that the new battery may have
slightly different charging requirements than the old one, if you want
to get the maximum service life out of it, but that's by no means
certain. Aside from that, the two should be compatible.


Watch out for gel cells that aren't rated for SMPS service. Those
suckers get drawn down _fast_, and lots of the cheaper ones won't
survive. (Ask me how I know.)

Cheers

Phil Hobbs

I've had that same question. I get that cheapo batteries are typically
lower quality. But how do you tell that an expensive battery isn't just
a cheapo battery with a higher price tag? They all seem to have the same
specs.
Any advice on brands?

I've had good luck with the on-shore and European brands, e.g. Varta.
IME usually there's a sticker inside the unit or a table in the manual
that gives recommended battery types.

I tend to buy used IBM e-server UPSes, which are rebranded APC SmartUPS
units, and seem to go much cheaper than the APC-branded ones. I've got
three 750 VA ones for $50 each, so even with a $60 battery it's still
pretty affordable. (The supplies themselves seem pretty bulletproof.)

Cheers

Phil Hobbs

I buy my UPSes at garage sales. They're the cheapo consumer toys that went
dead and were left in the garage a few more years. Batteries are always
toast.
Power around here rarely goes out for more than a second. If it's out
longer than that, it's probably gonna be out for longer than an affordable
UPS could handle. Current system is down to about a minute run time.
Should replace the battery.

I'm not a big fan of the consumer models, e.g. the APC BackUPS. The
SmartUPSes connect to the server, and in Gnome, the battery icon on the
desktop automatically tells you what the UPS is doing. I assume Windows
does something similar. They're also much better built, so for $50,
they're an excellent deal.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

 

[mike]

On 10/10/2012 2:46 PM, Phil Hobbs wrote:

On 10/10/2012 03:45 PM, mike wrote:
On 10/10/2012 9:48 AM, Phil Hobbs wrote:
On 10/09/2012 08:20 PM, mike wrote:
On 10/9/2012 1:02 PM, Phil Hobbs wrote:
On 10/09/2012 03:50 PM, Dave Platt wrote:
I had to do an emergency replacement last weekend. The bad
battery was:

12vdc, 4 amp hour gell cell

All I could find locally was:

12vdc, 5 amp hour gell cell


The batteries are identical except for the amp hour ratings.

I don't *think* moving up an amp hour should be a problem with this
type of battery. Am I right?

Very probably. It is *possible* that the new battery may have
slightly different charging requirements than the old one, if you
want
to get the maximum service life out of it, but that's by no means
certain. Aside from that, the two should be compatible.


Watch out for gel cells that aren't rated for SMPS service. Those
suckers get drawn down _fast_, and lots of the cheaper ones won't
survive. (Ask me how I know.)

Cheers

Phil Hobbs

I've had that same question. I get that cheapo batteries are typically
lower quality. But how do you tell that an expensive battery isn't just
a cheapo battery with a higher price tag? They all seem to have the
same
specs.
Any advice on brands?

I've had good luck with the on-shore and European brands, e.g. Varta.
IME usually there's a sticker inside the unit or a table in the manual
that gives recommended battery types.

I tend to buy used IBM e-server UPSes, which are rebranded APC SmartUPS
units, and seem to go much cheaper than the APC-branded ones. I've got
three 750 VA ones for $50 each, so even with a $60 battery it's still
pretty affordable. (The supplies themselves seem pretty bulletproof.)

Cheers

Phil Hobbs

I buy my UPSes at garage sales. They're the cheapo consumer toys that
went
dead and were left in the garage a few more years. Batteries are always
toast.
Power around here rarely goes out for more than a second. If it's out
longer than that, it's probably gonna be out for longer than an
affordable
UPS could handle. Current system is down to about a minute run time.
Should replace the battery.

I'm not a big fan of the consumer models, e.g. the APC BackUPS. The
SmartUPSes connect to the server, and in Gnome, the battery icon on the
desktop automatically tells you what the UPS is doing. I assume Windows
does something similar. They're also much better built, so for $50,
they're an excellent deal.

Cheers

Phil Hobbs

APC would be a step up for me ;-)

I have no need to know what the UPS is doing.
The lights going out are my clue that something
happened.
It's always good to match the tool to the job.
For me, a free garage sale ups that keeps my system
from resetting on a 1-second power glitch gives
me all the bang for none of the buck ;-)
But it is time to get a new battery for it.

 

[Phil Hobbs]

mike wrote:

On 10/10/2012 2:46 PM, Phil Hobbs wrote:
On 10/10/2012 03:45 PM, mike wrote:
On 10/10/2012 9:48 AM, Phil Hobbs wrote:
On 10/09/2012 08:20 PM, mike wrote:
On 10/9/2012 1:02 PM, Phil Hobbs wrote:
On 10/09/2012 03:50 PM, Dave Platt wrote:
I had to do an emergency replacement last weekend. The bad
battery was:

12vdc, 4 amp hour gell cell

All I could find locally was:

12vdc, 5 amp hour gell cell


The batteries are identical except for the amp hour ratings.

I don't *think* moving up an amp hour should be a problem with this
type of battery. Am I right?

Very probably. It is *possible* that the new battery may have
slightly different charging requirements than the old one, if you
want
to get the maximum service life out of it, but that's by no means
certain. Aside from that, the two should be compatible.


Watch out for gel cells that aren't rated for SMPS service. Those
suckers get drawn down _fast_, and lots of the cheaper ones won't
survive. (Ask me how I know.)

Cheers

Phil Hobbs

I've had that same question. I get that cheapo batteries are typically
lower quality. But how do you tell that an expensive battery isn't just
a cheapo battery with a higher price tag? They all seem to have the
same
specs.
Any advice on brands?

I've had good luck with the on-shore and European brands, e.g. Varta.
IME usually there's a sticker inside the unit or a table in the manual
that gives recommended battery types.

I tend to buy used IBM e-server UPSes, which are rebranded APC SmartUPS
units, and seem to go much cheaper than the APC-branded ones. I've got
three 750 VA ones for $50 each, so even with a $60 battery it's still
pretty affordable. (The supplies themselves seem pretty bulletproof.)

Cheers

Phil Hobbs

I buy my UPSes at garage sales. They're the cheapo consumer toys that
went
dead and were left in the garage a few more years. Batteries are always
toast.
Power around here rarely goes out for more than a second. If it's out
longer than that, it's probably gonna be out for longer than an
affordable
UPS could handle. Current system is down to about a minute run time.
Should replace the battery.

I'm not a big fan of the consumer models, e.g. the APC BackUPS. The
SmartUPSes connect to the server, and in Gnome, the battery icon on the
desktop automatically tells you what the UPS is doing. I assume Windows
does something similar. They're also much better built, so for $50,
they're an excellent deal.

Cheers

Phil Hobbs

APC would be a step up for me ;-)
I have no need to know what the UPS is doing.
The lights going out are my clue that something
happened.
It's always good to match the tool to the job.
For me, a free garage sale ups that keeps my system
from resetting on a 1-second power glitch gives
me all the bang for none of the buck ;-)
But it is time to get a new battery for it.

The idea is that the computer can shut itself down before the power goes
off, to avoid massive file system corruption. If your computers are
usually not doing very much, that's much less of a danger.

Cheers

Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510
845-480-2058

hobbs at electrooptical dot net
http://electrooptical.net

 

[klem kedidelhopper]

On Oct 10, 8:55 pm, mike <spam...@gmail.com> wrote:

On 10/10/2012 2:46 PM, Phil Hobbs wrote:







On 10/10/2012 03:45 PM, mike wrote:
On 10/10/2012 9:48 AM, Phil Hobbs wrote:
On 10/09/2012 08:20 PM, mike wrote:
On 10/9/2012 1:02 PM, Phil Hobbs wrote:
On 10/09/2012 03:50 PM, Dave Platt wrote:
I had to do an emergency replacement last weekend. The bad
battery was:

12vdc, 4 amp hour gell cell

All I could find locally was:

12vdc, 5 amp hour gell cell

The batteries are identical except for the amp hour ratings.

I don't *think* moving up an amp hour should be a problem with this
type of battery. Am I right?

Very probably. It is *possible* that the new battery may have
slightly different charging requirements than the old one, if you
want
to get the maximum service life out of it, but that's by no means
certain. Aside from that, the two should be compatible.

Watch out for gel cells that aren't rated for SMPS service. Those
suckers get drawn down _fast_, and lots of the cheaper ones won't
survive. (Ask me how I know.)

Cheers

Phil Hobbs

I've had that same question. I get that cheapo batteries are typically
lower quality. But how do you tell that an expensive battery isn't just
a cheapo battery with a higher price tag? They all seem to have the
same
specs.
Any advice on brands?

I've had good luck with the on-shore and European brands, e.g. Varta.
IME usually there's a sticker inside the unit or a table in the manual
that gives recommended battery types.

I tend to buy used IBM e-server UPSes, which are rebranded APC SmartUPS
units, and seem to go much cheaper than the APC-branded ones. I've got
three 750 VA ones for $50 each, so even with a $60 battery it's still
pretty affordable. (The supplies themselves seem pretty bulletproof.)

Cheers

Phil Hobbs

I buy my UPSes at garage sales. They're the cheapo consumer toys that
went
dead and were left in the garage a few more years. Batteries are always
toast.
Power around here rarely goes out for more than a second. If it's out
longer than that, it's probably gonna be out for longer than an
affordable
UPS could handle. Current system is down to about a minute run time.
Should replace the battery.

I'm not a big fan of the consumer models, e.g. the APC BackUPS. The
SmartUPSes connect to the server, and in Gnome, the battery icon on the
desktop automatically tells you what the UPS is doing. I assume Windows
does something similar. They're also much better built, so for $50,
they're an excellent deal.

Cheers

Phil Hobbs

APC would be a step up for me ;-)
I have no need to know what the UPS is doing.
The lights going out are my clue that something
happened.
It's always good to match the tool to the job.
For me, a free garage sale ups that keeps my system
from resetting on a 1-second power glitch gives
me all the bang for none of the buck ;-)
But it is time to get a new battery for it.

I buy my batteries from the local Batteries Plus store and they sell
the "Werker" brand. These are probably not top of the line but they
are cost effective batteries for service work. For emergency lighting
applications I've noticed that the equipment seems to charge the
batteries quite heavily and so they last only about three years. Most
alarm systems will go about five. I designed and built the charger for
my own alarm system. I use a common 12 volt 7 amp hour battery and I
trickle charge it at about a 10ma. rate. This is easily done by
putting a small incandescent lamp in series with the charging current.
When the battery is low the lamp is lit. As the terminal voltage
increases the lamp dims and eventually goes out. The exact lamp
employed will depend on the battery type,and the magnitude of the
charging voltage applied. It's a bit of trial and error to find the
right lamp that will give you the trickle charge you're looking for
once the battery is fully charged, but it makes a great deal of
difference in the life of the battery. I've got almost 9 years on this
one so far and that's pretty remarkable for a Chinese Werker battery.
Lenny.

 

[who where]

On Wed, 10 Oct 2012 09:06:59 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:

I've found that the quality and survivability of gel cells can be
estimated by their weight. Light weight batteries don't have enough
lead and will die an early death. The differences are fairly subtle
for small 50A-hr gel cells, but become obvious with the bigger
batteries.
http://groups.google.com/group/sci.electronics.repair/msg/d2e2cb9eb130b695

I don't know what constitutes a SMPS (UPS) rated gel cell.

In a particular size/case manufacturers often list a couple of types,
aimed at general duty and UPS-type duty. The latter are reputedly
optimised for the higher discharge rate found in that role compared to
the more urbane alarm system backup role (which only hits decent
discharge current if an audible alarm device is exercised).

The batteries I buy claim that the battery can be used in everything
from electric toy cars to USP's with little distinction as to type of
service.

Claims and reality are often strangers.

What I've found is that many UPS's over charge their
batteries.

Indeed. IMOE the things that kill UPS batteries are:

1. excessive float voltage
2. the heat that results from 1
3. far too aggressive recharge after discharge

A bit off-(thread)-topic, but I have a $20k+ communicatios test set
that uses Gates cylindrical sealed lead-acid cells in the battery
pack. The inbuilt charger design was such that these sets seem to
kill packs ina couple of years. Tiring of this recurrent cost, I
rejigged the charging circuit some 12 years ago, and haven't had a
pack die since. Sample of one isn't generally considered
statistically significant, but this is to me.

Measure the charge current at various discharge levels and
I suspect you'll find that many UPS's are trying to squeeze the last
bit of power out of their batteries in order to give longer runtime.

Just as laptops do ...

They also tend to recharge rather quickly, in order to deal with
repetitive power failures.

Yes, almost universally.

I had a running battle with APC over this issue on some of their
products. Note the pile of rack mounted (forgot the model number) APC
UPS's piled up on my deck:
http://802.11junk.com/jeffl/pics/home/slides/BL-house3.html
There were many many more that were ummm... recycled because the
batteries got hot, bulged, and eventually leaked electrolyte all over
the equipment. This UPS used four 12V 7A gel cells in a 24V
series/parallel combination.

I have been called on to "service" quite a number of failed soho UPS'
of varying sizes from 150W to 4kW, mostly APC. The electronics are
almost universally fine - except for one with dead FETs in the
inverter, the failure mode in every single one was batteries. When I
bothered to check the charge regime, it was found to implement the
above rules 1 and 3 on how to kill UPS batteries.

 

[tm]

"who where" <noone@home.net> wrote in message
news:hbue78914q7bbk913e02oh255t8llp83od@4ax.com...

Indeed. IMOE the things that kill UPS batteries are:

1. excessive float voltage
2. the heat that results from 1
3. far too aggressive recharge after discharge

A bit off-(thread)-topic, but I have a $20k+ communicatios test set
that uses Gates cylindrical sealed lead-acid cells in the battery
pack. The inbuilt charger design was such that these sets seem to
kill packs ina couple of years. Tiring of this recurrent cost, I
rejigged the charging circuit some 12 years ago, and haven't had a
pack die since. Sample of one isn't generally considered
statistically significant, but this is to me.

This does sound like maybe an IFR communications service monitor.
If so, can you give any details on your mod?

Thanks

tm

 

[Jeff Liebermann]

On Fri, 12 Oct 2012 10:14:58 +0800, who where <noone@home.net> wrote:

A bit off-(thread)-topic, but I have a $20k+ communicatios test set
that uses Gates cylindrical sealed lead-acid cells in the battery
pack.

Sounds familiar. I have an IFR-1500 that uses those Gates cells.
They're really made for alarm system use, not for a power hungry
1980's service monitor. It would kill off 6 batteries every 2 years
or so. I have up, removed the internal batteries, and run it off a
big gel cell when needed.

The inbuilt charger design was such that these sets seem to
kill packs ina couple of years. Tiring of this recurrent cost, I
rejigged the charging circuit some 12 years ago, and haven't had a
pack die since. Sample of one isn't generally considered
statistically significant, but this is to me.

Good idea. Incidentally, IFR power supply design is just plain weird
and difficult to repair. Mine have been down for many months because
the AC section of the power supply won't play switcher. So far, I've
replaced literally everything that could possibly cause a problem
without results. I'm running it on the DC section which fortunately
still works.

Measure the charge current at various discharge levels and
I suspect you'll find that many UPS's are trying to squeeze the last
bit of power out of their batteries in order to give longer runtime.

Just as laptops do ...

The joy of specmanship. If I'm lucky, and can find a way to reduce
charge current or float voltage limit in software, I can usually
extend the battery life. However, that's often impossible without
inside information or reverse engineering. I see far too many laptops
eat batteries due to overheating and overcharging in laptops that have
never been run on battery power.

They also tend to recharge rather quickly, in order to deal with
repetitive power failures.

Yes, almost universally.

I've often wondered if there's a recharge time spec for UPS's. A few
quick Google searches didn't find anything. I can see why the UPS
manufacturers would want to recharge quickly, but they should at least
give the customer the choice between fast recharge and long battery
life.

I had a running battle with APC over this issue on some of their
products. Note the pile of rack mounted (forgot the model number) APC
UPS's piled up on my deck:
http://802.11junk.com/jeffl/pics/home/slides/BL-house3.html
There were many many more that were ummm... recycled because the
batteries got hot, bulged, and eventually leaked electrolyte all over
the equipment. This UPS used four 12V 7A gel cells in a 24V
series/parallel combination.

I have been called on to "service" quite a number of failed soho UPS'
of varying sizes from 150W to 4kW, mostly APC. The electronics are
almost universally fine - except for one with dead FETs in the
inverter, the failure mode in every single one was batteries. When I
bothered to check the charge regime, it was found to implement the
above rules 1 and 3 on how to kill UPS batteries.

Yep. I've had similar experiences. I don't see many big UPS's but
overcharging is epidemic on small UPS's.

Rhetorical question:
Why are there no UPS's that use Li-Ion batteries?
Spoiler:
<http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries>


--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[who where]

On Thu, 11 Oct 2012 23:06:55 -0400, "tm" <No_one_home@white-house.gov>
wrote:

"who where" <noone@home.net> wrote in message
news:hbue78914q7bbk913e02oh255t8llp83od@4ax.com...

A bit off-(thread)-topic, but I have a $20k+ communicatios test set
that uses Gates cylindrical sealed lead-acid cells in the battery
pack. The inbuilt charger design was such that these sets seem to
kill packs ina couple of years. Tiring of this recurrent cost, I
rejigged the charging circuit some 12 years ago, and haven't had a
pack die since. Sample of one isn't generally considered
statistically significant, but this is to me.


This does sound like maybe an IFR communications service monitor.

Yep, 1200S

If so, can you give any details on your mod?

Well, it was 12 or so years back. I may have documented the change
somewhere, and I'll look through my mountain of "design notes" for it,
but I wouldn't go without food and drink waiting if I were you. I
certainly didn't put the note in the Service Manual.