Belkin UPS won't turn back on

[Assyrian.Bull]

The other day I did a battery test on my Belkin F6C100 UPS (which is
done by pressing the power button on the front of it) and the thing
just died. I tried disconnecting everything from the UPS and pressing
(and holding) the power button, but the UPS isn't turning on. I also
tried leaving it plugged in the wall overnight to see if it would
recharge, but nothing. Is this a symptom of dead batteries? I thought
that even if the batteries are dead in the UPS, it should still turn
on, but just not hold a charge. Could something have happened to the
electronics inside?

I took my digital multimeter and tested the outlets on the back of the
UPS and the ones linked to the battery backup show no voltage, but the
outlets used only as surge protection still work. I hate to buy new
batteries for the UPS just to find out that it's not the problem. Any
help would be appreciated.

Thanks,
Ray

 

[kony]

The other day I did a battery test on my Belkin F6C100 UPS (which is
done by pressing the power button on the front of it) and the thing
just died. I tried disconnecting everything from the UPS and pressing
(and holding) the power button, but the UPS isn't turning on. I also
tried leaving it plugged in the wall overnight to see if it would
recharge, but nothing. Is this a symptom of dead batteries? I thought
that even if the batteries are dead in the UPS, it should still turn
on, but just not hold a charge. Could something have happened to the
electronics inside?

It could have a safety shutdown that keeps it from working
if the batteries are dead- but I dont' know for certain
since I don't have one.

Keep it unplugged from the wall AC and take out the battery
(disconnecting both of the terminal wires) and leave it
disconnected for at least several minutes, use the
multimeter to take a voltage reading while disconnected from
the UPS.

With battery still out, plug the ups into the wall outlet
(only if it can be done safely, if it does not expose you to
the internals of the UPS and thus, high voltage, with it
appears to do since it has the design with the outer shell
over the whole thing, _OR_ IF you feel competent dealing
with it open- your judgement only), and then use multimeter
to measure whether voltage is applied to the battery leads
(as it would to charge the battery).

I took my digital multimeter and tested the outlets on the back of the
UPS and the ones linked to the battery backup show no voltage, but the
outlets used only as surge protection still work.

I hate to buy new
batteries for the UPS just to find out that it's not the problem. Any
help would be appreciated.

What batteries does it use?
How old is it? If old enough, it might be time to buy new
batter(ies) anyway.

If the battery is completely flat (voltage) it's probably
dead, but if you have the means to use another power source
(like any random 12V DC wall-wart) to try to put a trickle
charge into the battery, you might see if it's holding a
charge outside of the UPS... but since your charger isn't
meant for this purpose, take care not to leave it sitting
for days on end till it might overcharge... considering a
typical 1A @ 12V wall-wart, 8 hours should be plenty of time
to determine if holding a charge, or disconnect far sooner
to see if charging seems to be progressing or if the battery
is getting hot (don't leave it unattended at high trickle
rate inside a home if applicable).

If the battery charges up past 12V like this, don't worry so
much about topping it off the rest of the way, put it inside
the UPS again and see what the UPS does.

 

[Assyrian.Bull]

It could have a safety shutdown that keeps it from working
if the batteries are dead- but I dont' know for certain
since I don't have one.

Keep it unplugged from the wall AC and take out the battery
(disconnecting both of the terminal wires) and leave it
disconnected for at least several minutes, use the
multimeter to take a voltage reading while disconnected from
the UPS.

With battery still out, plug the ups into the wall outlet
(only if it can be done safely, if it does not expose you to
the internals of the UPS and thus, high voltage, with it
appears to do since it has the design with the outer shell
over the whole thing, _OR_ IF you feel competent dealing
with it open- your judgement only), and then use multimeter
to measure whether voltage is applied to the battery leads
(as it would to charge the battery).




What batteries does it use?
How old is it? If old enough, it might be time to buy new
batter(ies) anyway.

The UPS uses two sealed lead acid batteries (each of which are pretty
heavy). The batteries are at least 2 years old, and it's typical of the
cheap UPSs for their batteries to die within 2 years or so.

If the battery is completely flat (voltage) it's probably
dead, but if you have the means to use another power source
(like any random 12V DC wall-wart) to try to put a trickle
charge into the battery, you might see if it's holding a
charge outside of the UPS... but since your charger isn't
meant for this purpose, take care not to leave it sitting
for days on end till it might overcharge... considering a
typical 1A @ 12V wall-wart, 8 hours should be plenty of time
to determine if holding a charge, or disconnect far sooner
to see if charging seems to be progressing or if the battery
is getting hot (don't leave it unattended at high trickle
rate inside a home if applicable).

If the battery charges up past 12V like this, don't worry so
much about topping it off the rest of the way, put it inside
the UPS again and see what the UPS does.

I tested one of the batteries and it's completely dead. No voltage or
current across the terminals. The other battery, however, is holding
about a 3V charge with about 0.3A. When I try to connect the UPS
battery leads to the multimeter (when plugged in to the wall and
batteries disconnected), there's no voltage or current registered
across the leads. I don't know if this is a result of some kind of
safety switch, or if the circuitry inside the UPS is fried. It seems
like I might have to get a new UPS since the lack of any voltage or
current across the leads probably means there's something else wrong
here.

 

[kony]

The UPS uses two sealed lead acid batteries (each of which are pretty
heavy). The batteries are at least 2 years old, and it's typical of the
cheap UPSs for their batteries to die within 2 years or so.

I'm not so sure about this, I've had plenty of UPS that
didn't kill the batteries in 2 years, BUT I don't run the
batteries down all the way if there's a power outtage and
outtages don't happen very often, so it's not necessarily a
direct comparison.

I tested one of the batteries and it's completely dead. No voltage or
current across the terminals. The other battery, however, is holding
about a 3V charge with about 0.3A.

This is after you attempted to recharge them or not?
Was the 0.3A a load on it, current flowing from it during
the voltage reading, or an active supply current into the
cells? How long had the 0.3A been applied if an active
trickle charge?

If you used an alternate power source of roughly 12V and
over a few dozen mA, connected to either (both one at a
time) battery and one did not take a charge, it seems
obvious enough that you do at least have a battery failure,
but so far as determining if the UPS is ok now, that's
another story- it probably is but I wouldn't conclude it
without more supporting evidence.

I don't see your exact environment, more detail might help.
If you had an unregulated DC charger for example, one that
was spec'd for less than 300mA then while recharging a
battery from flat (or nearly so), it would be expected to
have a voltage depression until the output current
decreased.

The attempt to recharge was an important factor, as it could
be that your batteries are dead because the UPS charger
isn't working, but to know this, you'd have to know if the
batteries will hold a charge (charged separately, not in
series as 24V if that is how they were configured in the
UPS).

When I try to connect the UPS
battery leads to the multimeter (when plugged in to the wall and
batteries disconnected), there's no voltage or current registered
across the leads. I don't know if this is a result of some kind of
safety switch, or if the circuitry inside the UPS is fried. It seems
like I might have to get a new UPS since the lack of any voltage or
current across the leads probably means there's something else wrong
here.

I would've expected there to be a voltage between the UPS
battery leads, but again I don't have this UPS and can't see
it. Maybe a really good top-down picture of the circuit
board(s) would help (posted elsewhere and linked here), or
maybe not... as it's not quite the same thing as poking
around in person.

Not knowing if you are able to trace back circuits, I
hesitate to advise that you reverse engineer the UPS enough
to trace back the path of the recharging circuit and take
voltage measurements at each point. In particular, check
output of any small transformer and if there are fuses
inline with this battery charge circuit, measure their
continuity (if ceramic or a poly/other solid fuse, the glass
bodied fuses should be obvious enough from visual
inspection).

Now the less scrupulous suggestion- Buy another UPS from
someplace with a good return policy and swap the batteries
back and forth. If it turns out that the old UPS works with
the new batteries, put them back in the new UPS and return
it, and buy new batteries.

What about the indicator lights on the front, I presume it
has some, what do they indicate?

 

[Assyrian.Bull]

I'm not so sure about this, I've had plenty of UPS that
didn't kill the batteries in 2 years, BUT I don't run the
batteries down all the way if there's a power outtage and
outtages don't happen very often, so it's not necessarily a
direct comparison.

 

[Assyrian.Bull]

Not exactly sure what happened to my reply but I'll try again.

I'm not so sure about this, I've had plenty of UPS that
didn't kill the batteries in 2 years, BUT I don't run the
batteries down all the way if there's a power outtage and
outtages don't happen very often, so it's not necessarily a
direct comparison.




This is after you attempted to recharge them or not?
Was the 0.3A a load on it, current flowing from it during
the voltage reading, or an active supply current into the
cells? How long had the 0.3A been applied if an active
trickle charge?

I tested the batteries both before and after I attempted a recharge.
One of the batteries is completely dead, no voltage or current. The
other, however, does hold a slight charge, and may not be worthless
just yet. The 0.3A reading from taken from the battery terminals (of
the one that still alive), after a short recharge was done.

If you used an alternate power source of roughly 12V and
over a few dozen mA, connected to either (both one at a
time) battery and one did not take a charge, it seems
obvious enough that you do at least have a battery failure,
but so far as determining if the UPS is ok now, that's
another story- it probably is but I wouldn't conclude it
without more supporting evidence.

I don't see your exact environment, more detail might help.
If you had an unregulated DC charger for example, one that
was spec'd for less than 300mA then while recharging a
battery from flat (or nearly so), it would be expected to
have a voltage depression until the output current
decreased.

The attempt to recharge was an important factor, as it could
be that your batteries are dead because the UPS charger
isn't working, but to know this, you'd have to know if the
batteries will hold a charge (charged separately, not in
series as 24V if that is how they were configured in the
UPS).


I would've expected there to be a voltage between the UPS
battery leads, but again I don't have this UPS and can't see
it. Maybe a really good top-down picture of the circuit
board(s) would help (posted elsewhere and linked here), or
maybe not... as it's not quite the same thing as poking
around in person.

Not knowing if you are able to trace back circuits, I
hesitate to advise that you reverse engineer the UPS enough
to trace back the path of the recharging circuit and take
voltage measurements at each point. In particular, check
output of any small transformer and if there are fuses
inline with this battery charge circuit, measure their
continuity (if ceramic or a poly/other solid fuse, the glass
bodied fuses should be obvious enough from visual
inspection).

From looking at the internals of the UPS, the positive battery lead is

connected to a large transformer, while the negative lead is connected
directly to the circuit board. I could start to trace back and see if
the recharging circuit is at fault, but it doesn't seem like it would
be worth it on a UPS such as this one. It wasn't that expensive to
begin with and if that were the problem, I'd end up replacing it
instead of reparing it. The fuses, on the other hand, look fine.

Now the less scrupulous suggestion- Buy another UPS from
someplace with a good return policy and swap the batteries
back and forth. If it turns out that the old UPS works with
the new batteries, put them back in the new UPS and return
it, and buy new batteries.

What about the indicator lights on the front, I presume it
has some, what do they indicate?

I think I'm going to try the swap and see if that works. I'm sure I can
find batteries that are similar enough from another Belkin UPS to see
if that's the problem. The LEDs unfortunately don't tell me anything
since nothing lights up on the UPS.

 

[Joe Morris]

Not exactly sure what happened to my reply but I'll try again.

I tested the batteries both before and after I attempted a recharge.
One of the batteries is completely dead, no voltage or current. The
other, however, does hold a slight charge, and may not be worthless
just yet. The 0.3A reading from taken from the battery terminals (of
the one that still alive), after a short recharge was done.

Some UPS designs will not turn on the charger if there's no indication
that a battery is connected. At box startup the logic looks for
voltage on the battery connections and if it doesn't find some
minimal amount (dependent on the UPS design) the startup process
is abandoned, perhaps because the electronics was designed to require
the presence of the battery as a critical part of the circuit.

This would be consistent with your failure to see any voltage across
the battery leads. Several years ago in my office I was using a
large (2000 VA) rackmount APC box that used four, 18 A-H batteries.
I found out the hard way after some power outages that marginal
batteries could take the net battery box voltage below the startup
limit; my fix was to use an automotive start booster to keep the
charger in the UPS turned on until the batteries would put out
enough voltage to keep the box on without assistance.

Joe Morris