I went to use a Smart-UPS 700 (true sine wave) after letting it sit for
a couple of years, and nothing happened -- plugging it in yielded no
LEDs, sounds, etc. Pressing the power on, off, circuit breaker, and
reset did nothing. The two 120V receptacles (wall plugs) I tried are good.

I disassembled the unit, and found conductivity through the power wires,
the circuit breaker, and leads to the mainboard. The two 30A 32V fuses
to the batteries are fine, but, as expected the batteries are totally
dead after sitting for a couple of years.

I didn't see any obvious damage to the UPS at all -- no hot parts or
connections. There was continuity, separately, through the two
transformer windings. I jiggled all the connectors and reassembled the
unit, and there was no change, even after leaving it plugged in for a
half-hour.

What else could cause absolutely no response from this UPS? Anyone else
had this experience with an APC UPS, and did you overcome it? Seems
like too nice hardware to just trash (after recycling the batteries).

Thanks in advance.

-Brian

Brian wrote:
I went to use a Smart-UPS 700 (true sine wave) after letting it sit
for a couple of years, and nothing happened -- plugging it in yielded
no LEDs, sounds, etc. Pressing the power on, off, circuit breaker,
and reset did nothing. The two 120V receptacles (wall plugs) I tried
are good.

I disassembled the unit, and found conductivity through the power
wires, the circuit breaker, and leads to the mainboard. The two 30A
32V fuses to the batteries are fine, but, as expected the batteries
are totally dead after sitting for a couple of years.

I didn't see any obvious damage to the UPS at all -- no hot parts or
connections. There was continuity, separately, through the two
transformer windings. I jiggled all the connectors and reassembled
the unit, and there was no change, even after leaving it plugged in
for a half-hour.

What else could cause absolutely no response from this UPS? Anyone
else had this experience with an APC UPS, and did you overcome it?
Seems like too nice hardware to just trash (after recycling the
batteries).

Thanks in advance.

-Brian


The battery is dead. For whatever reason, this causes a lot of UPS's
to behave exactly as described. If it sat for several years, the
battery will not take a charge, it needs to be replaced.

Meat Plow wrote:

On Sat, 10 May 2008 07:42:57 -0500, Brian wrote:

James Sweet wrote:


The battery is dead. For whatever reason, this causes a lot of UPS's
to behave exactly as described. If it sat for several years, the
battery will not take a charge, it needs to be replaced.

Thanks for the responses.

Really? Absolutely nothing -- no attempts at all to recharge, not
even
flicker of the lights or a hum of the transformer? Dead as a
doornail ...


You might try to charge the batteries with a conventional charger or
variable power supply for an hour or so at a low current then replace
them in the unit.

Its unlikely that it will work.  The UPS does a self test upon switch on
which involves a load test on the battery.  If the battery cannot pass
this test the UPS just shuts down again.  Also they are sealed gell
types.  Although I must admit that I have in the past cracked off the
plastic bung and added water to try and recover them !  Without success
I might add.

Thanks, I'll give it a try!  I have a one-amp 12V trickle charger that I
use for cars.  Will let y'all know what happens, on Tuesday or so.

On Sat, 10 May 2008 07:42:57 -0500, Brian wrote:

You might try to charge the batteries with a conventional charger or
variable power supply for an hour or so at a low current then replace them
in the unit.

Meat Plow wrote:
On Sat, 10 May 2008 07:42:57 -0500, Brian wrote:

You might try to charge the batteries with a conventional charger or
variable power supply for an hour or so at a low current then replace
them
in the unit.

Thanks, I'll give it a try! I have a one-amp 12V trickle charger that I
use for cars. Will let y'all know what happens, on Tuesday or so.

Otherwise, I see cheapee replacement batteries on eBay, ~$40 delivered
for the needed two batteries.

-Brian

Beware cheap Chinese knockoff batteries, they've been known to fail
quickly and/or leak.

That isn't the issue here. It's the fact that lead-acid cells can be
destroyed by a single full discharge.

By the way, I've seen primary alkaline and lithium cells reverse-charged.

What other kind of rechargeable battery can be destroyed by running it all
the way down -- just ONCE?

Battteries are cells in series. If the battery pack discharges too
deeply, then current output by most cells can reverse charge the
weakest cell. Sometimes this can result in a short inside that one
cell. The entire battery is bad because too much discharging has
reverse charged and destroyed one cell. Its rare. But is does
happen.

There is a good chance that charging the batteries externally
won't do a thing but then you've not lost anything just giving it
a try.

I don't know if lead-acid gel cells are susceptible to sulfation
as are liquid-filled cells but that is a usual cause of failure from
liquid batteries being stored without a charge being maintained.

I don't want to discourage the OP from trying to recharge the battery -- be
sure to cover them with something thick and heavy, in case they rupture or
explode (I'm not trying to be funny) -- but when I recently pulled out a
Coleman fluorescent lantern powered by an E640 gel battery, I found it dead.
The several-years' lack of charging had allowed the battery to die.
Lead-acid batteries are fragile beasts.

I don't want the OP to blow himself up either but a small current applied
long enough to boost the voltage up to where the APC will charge them is
fairly innocuous. The Smart UPS 700 was a very popular small server backup
solution several years ago and I have experimented with them and their
batteries without causing death or dismemberment. And I would tend to
disagree with you regarding the fragility of lead-acid batteries in
general. They are exposed to some pretty harsh environmental conditions
every day in automotive and industrial use.

Note: Some SmartUPS units require 24 volts.. i.e. 2 12v batteries in series
to run.

Michael Kennedy wrote:

Note: Some SmartUPS units require 24 volts.. i.e. 2 12v batteries in
series to run.

Yes, this unit has two 12V batteries. New ones are on order! Shipping
is more than the batteries themselves ... they are heavy.

-Brian