dslreports logo
 
    All Forums Hot Topics Gallery
spc
Search similar:


uniqs
1644

Thane_Bitter
Inquire within
Premium Member
join:2005-01-20

Thane_Bitter to HiVolt

Premium Member

to HiVolt

Re: UPS batteries

Explains why it was melting, because of some fault that halved the voltage the battery was getting over charged. Good thing you found it when you did,

HiVolt
Premium Member
join:2000-12-28
Toronto, ON

HiVolt

Premium Member

Yeah, i just wonder why the UPS kept charging it when it already determined a battery fault, in the form of an email notification and the red light and beeping on the unit..

Spike5
Premium Member
join:2008-05-16
Toronto, ON

Spike5 to HiVolt

Premium Member

to HiVolt
said by HiVolt:

Interestingly enough I did measure... The battery that leaked only measured 6V, while the other one was still reading 12.6V.

Thats the overall battery voltage. A typical 12V SLA is made up of 6 2.0V cells. One would need to bust into the cap to tap into the bridge that leads over to the next cell.
I suspect a single cell on that side failed, likely it internally shorted, but I see no signs of puffing on that side below.

HiVolt
Premium Member
join:2000-12-28
Toronto, ON

HiVolt

Premium Member

Yeah, the battery wasn't swollen, it slid out of the UPS just fine. I know a thing or two about swollen ones, i've had to dismantle a few UPS'es to free them from the swollen up batteries.

I still have that busted battery, havent made my way yet to UPSforless to get it recycled, I brought it to work, i'll get to it when i have to get new batts for work UPS'es.

I wonder if i should try to hack the top off just to see, hehe... I do have protective equipment to try it at work, as we have quite a bit of harsh chemicals in the press/prepress environment.

Thane_Bitter
Inquire within
Premium Member
join:2005-01-20

Thane_Bitter to HiVolt

Premium Member

to HiVolt
It's more of an idiot light, bad batteries or a broken UPS can set it off. Playing around with mine I was able to reset the alarm by adjusting one of the timing settings so that it was below the current capacity of the batteries (which now is down to 5 minutes) and then run a self test. The batteries are still bad, but I don't have to listen to beeping.

According to APC's own documents the UPS can't really tell if the batteries are worn out or the charging system has failed. »sturgeon.apcc.com/kbasew ··· Document

HiVolt
Premium Member
join:2000-12-28
Toronto, ON

HiVolt

Premium Member

Click for full size
Click for full size
Heh, these things are impossible to take apart without destroying them....

It was completely dry, as no liquid inside that i could see spill out even when i flipped it over...

donoreo
Premium Member
join:2002-05-30
North York, ON

donoreo

Premium Member

that does not look good.

Thane_Bitter
Inquire within
Premium Member
join:2005-01-20

Thane_Bitter to HiVolt

Premium Member

to HiVolt
The acid is contained in the mats that are put between cells, allows these types of battery to be installed in any orientation, they should be damp.

HiVolt
Premium Member
join:2000-12-28
Toronto, ON

HiVolt

Premium Member

Oh... well i gutted it and tossed the bits in our hazardous waste bin already, i didnt wanna leave it and have it self combust or anything, if it had any energy left anyway in its torn up state, hehe...

Thane_Bitter
Inquire within
Premium Member
join:2005-01-20

Thane_Bitter

Premium Member

Well you found out what is inside.
If it was brand new everything inside would have appeared much cleaner and less sooted.

Spike5
Premium Member
join:2008-05-16
Toronto, ON

Spike5 to Thane_Bitter

Premium Member

to Thane_Bitter
Yup, cooked. If the leftmost cell shorted out (looks certainly indeed the case), then the remaining 5 cells would had got overcharged substantially.

koira
Hey Siri Walk Me
Premium Member
join:2004-02-16

koira to HiVolt

Premium Member

to HiVolt
Are you confident the UPS charging system is still working properly ? I'm wondering if that thing might not be sensing the charge state of the battery and continues pushing current after it should shut off. Hence overcharging / boil dry / melt down ?

HiVolt
Premium Member
join:2000-12-28
Toronto, ON

HiVolt

Premium Member

said by koira:

Are you confident the UPS charging system is still working properly ? I'm wondering if that thing might not be sensing the charge state of the battery and continues pushing current after it should shut off. Hence overcharging / boil dry / melt down ?

How would I test that? the UPS gives no indication if it's charging or not.

Thane_Bitter
Inquire within
Premium Member
join:2005-01-20

Thane_Bitter

Premium Member

On an SU smart-UPS the fan should kick on whenever the charger runs or it is on battery power (the inverter is the battery charger).

Really its just a matter of watching the voltage on the battery pack as it charges. Usual warnings of death and destruction when dealing with a bunch of high amperage batteries. You may have to make some purpose built leads to connect to the terminals.

koira
Hey Siri Walk Me
Premium Member
join:2004-02-16

koira to HiVolt

Premium Member

to HiVolt
Disclaimer: I'm comparing the failure in the UPS to a similar car battery charging circuit. The charging situation is similar. Obviously the UPS has the ability to sense line voltage level and draw off the battery to run the inverter to create line level.

Assuming its a 12 volt system with lead acid battery

The charged battery voltage, while not on charge should be around 12.4 to 12.9 VDC

Then check the voltage across the battery terminals while charging , if you measure greater than 14.7 VDC it's likely overcharging.

HiVolt
Premium Member
join:2000-12-28
Toronto, ON

HiVolt

Premium Member

Yeah i'll have to check that with the battery door open and attach leads to the battery terminals, then pull the plug for a few minutes to discharge a bit, then check the voltage as it charges, and after when (and if) it stops.

This battery pack ran for well over 6 hours in the Ice Storm outage, so maybe draining it completely didnt help its cause being old already.

BTW, this is a SmartUPS 1500, its a 24V system, with 2x12V batteries in series.

koira
Hey Siri Walk Me
Premium Member
join:2004-02-16

1 edit

koira

Premium Member

double the voltages. look for 25 VDC reading on the battery terminals with charger off and a bit over 29 on charge

agreed, during the extended outage you probably ran whatever life was left after 5 years

I'm just thinking its worth a quick check of the charging circuit while its all opened up. Also if you haven't already worth checking the corresponding contacts inside the UPS considering the way the battery one melted.

HiVolt
Premium Member
join:2000-12-28
Toronto, ON

HiVolt

Premium Member

Yeah it discharged then sat dead for 3 days before the power came back... maybe if it was recharged right away or shortly after...

koira
Hey Siri Walk Me
Premium Member
join:2004-02-16

koira

Premium Member

any chance it froze a bit while discharged ?
that would help kill it

HiVolt
Premium Member
join:2000-12-28
Toronto, ON

HiVolt

Premium Member

No didn't freeze, it was in the basement. I had 3 other UPS'es there that survived fine.

Thane_Bitter
Inquire within
Premium Member
join:2005-01-20

Thane_Bitter

Premium Member

Deep discharges kill lead acid batteries, sealed or wet, it does the same damage. Deep cycle batteries will tolerate discharges better, its often why you see them used on boats, RVs and in homebrew UPS / solar power projects, placed in which charging is delayed or infrequent.

Picked up my batteries today, Donoreo is right, its right at the end of the second complex, very much out of sight. If you are buying a lot of RBC units, safe your spine and bring a handtruck. Glad I brought a bag that was strong enough to hold all 10 batteries (8 + 2), best .75 cents I spent at IKEA.

donoreo
Premium Member
join:2002-05-30
North York, ON

donoreo

Premium Member

Yeah, batteries are heavy Getting them for a rack mount unit is heavy!

Thane_Bitter
Inquire within
Premium Member
join:2005-01-20

Thane_Bitter

Premium Member

And to think I wanted to get an external battery compartment to add runtime, each one takes twice the number of batteries as the UPS; now not so much.

Guspaz
Guspaz
MVM
join:2001-11-05
Montreal, QC

Guspaz to Thane_Bitter

MVM

to Thane_Bitter
I love my external extended run packs. Triple the runtime. Yeah, they're heavy, that's what my folding handtruck is for.

Thane_Bitter
Inquire within
Premium Member
join:2005-01-20

Thane_Bitter

Premium Member

Was yours a rackmount or the tower style ones? If it is the tower type do the batteries go on the top of the UPS or under it?

Guspaz
Guspaz
MVM
join:2001-11-05
Montreal, QC

Guspaz to Thane_Bitter

MVM

to Thane_Bitter
Tower style. You put the extended-run battery pack beside the UPS and plug the connector cable between them. The extended-run battery pack is the exact same shape and size as the UPS itself, except it doesn't have any screen/buttons/sockets/etc on it. It's a BR1500G and BR24BPG battery pack.

I liked my old BR1500/BR24BP better in many ways, but there doesn't seem to be much choice on the market for affordable UPS that support extended run. A lot of people point to CyberPower as an alternative to APC, but they don't seem to sell consumer UPS with extended run capability.

Thane_Bitter
Inquire within
Premium Member
join:2005-01-20

Thane_Bitter

Premium Member

No there isn't and a lot of the smaller units will overheat if you try to run them (with external batteries) longer.

The older style APC Smart UPS tower UPS were neat in that they used the same guts as the rack mount versions. The 3000 and 2200 VA versions use the exact same board including the XL (extended runtime) versions. It is possible to go in an convert a regular 2200 (tower or rack) into the XL version as well as beef out the inverter charger by adding in more MOSFETS and adding the external battery plug. It is a bit of work to do that of course, lots of soldering and parts hunting.

The battery cabinets are a rip off as well, even used they want hundreds of dollars for what basically is nothing but a metal box, a set of leads and a fuse.
Thane_Bitter

Thane_Bitter

Premium Member

Finally got the new batteries installed yesterday but unfortunately the run-time of the UPS did not improve, the system needs to be re-calibrated.

HiVolt
Premium Member
join:2000-12-28
Toronto, ON

HiVolt

Premium Member

said by Thane_Bitter:

Finally got the new batteries installed yesterday but unfortunately the run-time of the UPS did not improve, the system needs to be re-calibrated.

Which UPS is it? If it's an APC with a serial port there's a handy utility called APCFix that calibrates it perfectly.

Thane_Bitter
Inquire within
Premium Member
join:2005-01-20

Thane_Bitter

Premium Member

It has it, was reading up on that program but its all Russian, was also looking at »www.apcupsd.com as well, they have the procedure for doing it over a terminal session if you know the constant. They have a partial list of values however the model I have isn't one of the units listed.

I don't want to do the manual calibration method, it appears you have to do it twice sometimes just to get the value right, that puts a bit of wear onto a new set of batteries.