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Uninteruptable Power Source Fuse trouble shoot,fuse location etc.

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BrianAlex

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Jan 5, 2009, 4:04:49 PM1/5/09
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Hi. I have a UPS that is not functioning correctly. It's an APC
"Professional Powercell" 250 watt
unit that is at least 5 years old.
When there is a power outage, it beeps loudly but there is no current
to the outlets (computer is plugged to this).
I took out the 12 v lead battery and it tests 13 volts.
I pushed the "re-set" button.
I dismantled the case ("no user serviceable parts) and there is a
note to use only the same size fuse. Well there is no indication where
the fuse is,and I believe this may be the problem since at one time I
had too much stuff plugged in (not being aware of it's 250 W limit).
There is an orangish part that looks like a plastic plug-in
automobile fuse that says"40" on top and on the solder side says "40A
32V". I checked from this side and it has continuity,plus the element
in it appears solid.
Would there be a fuse somewhere else? I don't see one.
Also I see a "APCC (C) 1993" on the board so maybe this thing is that
old.
What else would cause this failure?
I consider this a learning opportunity,and I am a cheap so-and-so and
will not be paying the big bucks for a new one any time soon!
Your advice greatly appreciated.-Brian

Ronbo

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Jan 5, 2009, 5:57:30 PM1/5/09
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That is the fuse but there is probably also a circuit breaker on the
back panel. If tripped a small blade will pop out. What model is it?

BrianAlex

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Jan 5, 2009, 6:11:17 PM1/5/09
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> back panel. If tripped a small blade will pop out. What model is it?- Hide quoted text -
>
> - Show quoted text -

The model is; "Professional Powercell" s/n; C94093679593 and yes,
it has the little blade that says "push,reset" around it (which I
did). Maybe this thing is toast,but I don't quit on stuff very easily.
Thx. BrianA

Bob Shuman

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Jan 5, 2009, 6:37:11 PM1/5/09
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Re-test the battery under load to see if you still are able to get the
nominal 13V.

Bob

"BrianAlex" <Brian...@hotmail.com> wrote in message
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who where

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Jan 5, 2009, 8:37:57 PM1/5/09
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On Mon, 5 Jan 2009 13:04:49 -0800 (PST), BrianAlex <Brian...@hotmail.com>
wrote:

Most common failure mode of this class of UPS is u/s battery. They dry out due
to overcharging. (The charge regimes employed are brutal on batteries, in the
interest of fast recovery). They present as fully charged in terms of terminal
voltage because they have a very small residual capacity, but can't cut the
mustard when it comes to driving the inverter even at idle.

Try connecting an automobile battery instead and see if the UPS functions. That
way you can quickly determine whether it is the battery or the electronics
causing the problem.

John Keiser

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Jan 5, 2009, 8:26:59 PM1/5/09
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In my experience, the batteries last no more than 5 years. If this is the
original battery, its time is likely up. Test under load or with a
substitute and replace for $25 or so.


--
Remove -NOSPAM- to contact me.


hr(bob) hofmann@att.net

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Jan 5, 2009, 10:03:02 PM1/5/09
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Unless you test the battery under load, you don't really know much of
anything. If it is too hard to connect the battery to the UPS when
the battery is out of the UPS unit, use an automobile back-up light or
something similar, but smaller than a headlight, and see if the
voltage really holds up under load.

BrianAlex

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Jan 5, 2009, 11:03:47 PM1/5/09
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On Jan 5, 7:03 pm, "hr(bob) hofm...@att.net" <hrhofm...@att.net>
wrote:

OK, glad I talked to you guys. I pulled the battery and found an
automobile tail-light bulb and it wouldn't even light that up! So I
then checked to see if the leads that normally connect to the battery
were supplying current and they are so I guess I'll just find a new
Bat. I'm used to testing my AAA batteries and if they read good they
are good, I see it's different with these lead ones. Thanks a lot
guys!

Jeff Liebermann

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Jan 5, 2009, 11:51:29 PM1/5/09
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On Mon, 5 Jan 2009 19:03:02 -0800 (PST), "hr(bob) hof...@att.net"
<hrho...@att.net> wrote:

>On Jan 5, 7:26 pm, "John Keiser" <john.keis...@hawaiiantel.net> wrote:
>> In my experience, the batteries last no more than 5 years.  If this is the
>> original battery, its time is likely up.  Test under load or with a
>> substitute and replace for $25 or so.

>Unless you test the battery under load, you don't really know much of


>anything. If it is too hard to connect the battery to the UPS when
>the battery is out of the UPS unit, use an automobile back-up light or
>something similar, but smaller than a headlight, and see if the
>voltage really holds up under load.

I got tired of dealing with guesswork on batteries. So, I bought
myself a Hanukkah present:
West Mountain Radio CBA-II.
<http://www.westmountainradio.com/CBA_ham.htm>
About $150 including the optional thermal sensor. I've been running
discharge curves on various batteries in my collection. I'm mostly
interested in how various Lithium technologies operate, but have had
time to mess with some 12v 7A gel UPS batteries. There's a rather
obvious difference between a new battery and one that's been
continuously (over)charging inside the UPS. I plan to post graphs,
but I'm not sure of my current settings and methodology, so that will
need to wait. For example, I was having problems with Powerpole
connector losses when I read comments at:
<http://www.westmountainradio.com/cbausers.htm>
by Bob WX2NJ (at bottom of page). At the rated 1c (7A) load, the
connector resistance resulted in a premature cutoff point.

Anyway, the CBA II is far more accurate and entertaining battery
tester than timing a fading auto tail light.

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

Arfa Daily

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Jan 6, 2009, 4:59:28 AM1/6/09
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"BrianAlex" <Brian...@hotmail.com> wrote in message
news:14ede51e-7bf8-4018...@c36g2000prc.googlegroups.com...

When you source a replacement battery, make sure that you get one with the
correct size terminal blades, not one of the 'alarm-style' types where the
terminals are only about half the width. These UPSs pull HUGE amounts of
current from the batts - witness the 40A automobile fuse that you found in
there - even when the load is light, and it is essential that there is a
really good connection to the battery, otherwise, even the small volt-drop
that you get from a less-than-ideal connection, is enough to fool the
control electronics into thinking that the battery is on its last legs,
which then makes the UPS shut back down, bleeping forlornly at you ... Trust
me, been there ... :-)

Arfa


hr(bob) hofmann@att.net

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Jan 6, 2009, 4:57:02 PM1/6/09
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On Jan 5, 10:51 pm, Jeff Liebermann <je...@cruzio.com> wrote:
> On Mon, 5 Jan 2009 19:03:02 -0800 (PST), "hr(bob) hofm...@att.net"
> Santa Cruz CA 95060http://802.11junk.com
> Skype: JeffLiebermann     AE6KS    831-336-2558

Jeff:

My idea worked, and it wasn't any $150.00 either. I'd rather spend
$150 on something more fun, like a new kitchen tv. <G>

Bob

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