1500 VA Uninterruptible Power Supply replacement after troubleshooting

Killed by Death

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Yesterday our UPS finally gave me the Lower Battery indications, it was beeping & complaining several times in the evening.
So this morning I turned it off:
unplugged it,
removed the two 5 Amp 12 Volt batteries,
measured them to determine which was low,

replaced the low one with a newer one from a smaller single-battery UPS, still the same brand & model that's in there - Duracell

accidentally flipped them to make the connections & Voila, welded the Positive terminal to the post/tab so badly that it destroyed it, wrong Polarity!

The problem now is that if I cut off the old terminal & crimp a new one on there, it will be too short to connector, or at least very difficult.

What I did was go shopping & found the F2 spade terminals designed for larger diameter wire:

1657386817978.png

like the Yellow one,
Now my plan is to cut off the spade part of the old connector, leaving the part that's crimped round the wire & just put the new yellow connector over it & crimp.
Not going to try until tomorrow morning, so thought I'd float this around in here to see if anyone had a better suggestion.

Right now it's working, but what I've done is just jam the melted spade connector on with the tab between the melted metal & the plastic shroud of it:

1657386993835.png

The original connectors are completely shrouded in insulation, like that^,
but if we're being honest it doesn't need to be, the inside where it goes has no bare metal.

I'm still going to carefully cut that insulator off (just one slit down the middle) & try to reapply it after getting the new spade on there, anyway.

I thought for sure I fried the whole unit for a minute & was about to weep a little, it's a $200 USD unit.
Taking it to a nearby shop would probably cost me about $50 USD. I took a speaker-cabinet there years ago for a new Capacitor in the crossover & they charged me a lot & didn't even use the correct value of Capacitor.

If my plan doesn't work, I'll start making some calls Monday to see who can fix it, & probably still go cheap & do it myself.
Yeah I know, the real fix would be to just run a new wire so it's long enough, but I'm not going to risk tearing this thing apart any further than the battery compartment.
 
The VAC incoming has been fluctuating all day, & now it's down to only 80 from a normal 120 VAC.
No wonder it was complaining so much last night, & maybe I didn't need to replace the battery at all.
However, tonight it's not complaining, it beeped once when I first put it back on this morning, but not a blip since.
I wouldn't be surprised if our power transformer blows again. It blew just a week ago & was out for 4 hours, on a weekend night, of course.

Their Power distribution leaves something to be desired. I haven't seen Power dips this low since I was in the Land of Smiles & Power would dip from 220 VAC to only 170 VAC during prime-time, when everyone was home cooking, taking showers & watching TV.

This is actually a little worse, 66% of the standard!
 
All done now, but I didn't need to cut off the old connector.
Once I got it on the table in the morning sunlight I could see that only a tiny bit of it had been arc-welded together, so I got out my precision screwdriver set.

Started with the smallest driver & carefully broke free the 'welded' spot & then pried it open to where the tab on the battery could be inserted!

It will probably be a real bear to get off later-on, but for now it's working perfectly.
 
It was working fine for a over a month & then started that beeping again, even though the batteries weren't low.
They weren't even low last time actually, but one just happened to be a little lower in Voltage than the other.
Manufacturer's advice was the batteries were kaput & I only had 1 other that's charged higher, which I already swapped in every possible combination.

Took it over to the local battery shop & the guy put two fresh batteries in it, still kaput.
So it's shagged, unless I can find a place to repair it, which is beyond frustrating when no one answers their phones anymore.

I took a look at their rechargeable batteries while I was there & will buy there next time instead of online. I can get a better deal online, but they deserve some loyalty for putting those new batteries in for no charge, & testing my old batteries.

The reason Radio Shack closed it because everyone started buying online.

I'm not driving all over town to find a place, so I may just purchase a refurbished replacement of the same model without batteries for a huge difference in price vs. a new one with batteries.

I like this model, it has a LCD display which tells you how much time you have left on the current load, when it's discharging.

Not bad for being in service for a decade, might have lasted longer if I hadn't made that stupid mistake, but I'm dubious about that, because it was already acting out of sorts, which is what started this whole saga.

I kind of wish I hadn't chronicled it here, since I got zero responses, except for one person weaponizing it against me in another thread.
 
I'd not worry about Chronicling it here, not the lack of responses. Some times It can take a while for the people with relevant skills to see a post so bumping it every few days is always a good option.

Generally it is always best to change all the batteries at the same time since you don't really want batteries with different life cycles in your UPS. Additionally a newer battery will be able to load and charge better than an older one, so you don't want mismatched battery cycles.

I've seen a couple of arching incidents from UPS' and they are never pretty. these batteries can deliver awfully high current levels and really need to be careful when dealing with them. I'm always in favour of people 'giving it a shot with with most tech after a bit of prior reading and knowledge seeking, but power supplies and devices with high power systems... far less so.

Its quite possible you damaged the electronics when the arcing occurred, so this may even be the cause of the issues you now face. Though of course its impossible to say for sure. 10 years for a UPS is a good length of service so don't feel too bad.
 
The two of them can deliver over 10 Amperes given a low Resistance load. There was no smoking gun, no smell of burning components. I would think if I wrecked it with a temporary reverse polarity it would not have been able to stay in service for another month.
It may have gone on figuratively forever if I hadn't forced it to power down.
I'm picking up another of the same model this afternoon, refurbished & without batteries, 33% of the cost of new.
I'm not a novice about Electricity, but sometimes we're the worst, because we become complacent.
I'd changed the batteries so many times that I just got sloppy, not taking my time & thinking about what I was doing.

Changing both batteries is a $100 job They're not cheap, but I did find a supplier yesterday where I can get two for $60 & I'll do that & relegate the leftovers to my smaller UPS for the computer & monitor.
 
Took the old unit out of the hot vehicle today & before taking the batteries out I gave it one last push on the Power button & Voila, it came on!

PXL_20220824_163649953.jpg


It seemed fine for a while, but before I put it back in service I let it just sit there & eventually it started beeping for no reason. The input is fine, the batteries are fine, but it won't shut up.
The Mute button does nothing but cycle through the various displays.

I'm not going to use it, because I don't like being woken up at 04:44 by incessant beeping, Ha!
It's acting exactly like it did prior to the reverse polarity arcing, but I'm really puzzled why it quit for days & then went back to its previous state.

I once had a bass guitar amp like that. If you took it out for a rehearsal, it was a crap-shoot whether it was going to perform poorly once it was taken out of the trunk, & I tried to handle it as carefully as possible.
 
Hmmm I'm still inclined to think it's the batteries. They are weird things since they can have a range of operating levels rather than a binary working/not working fault condition. If they can appear fully charged for example, but the charge doesn't last or can't be sustatined for the expected range of times/loads. Something that many not be clearly obvious with simple checks, but can be detected with more detailed analysis either with external tests, or that can be detected by the UPS. Do you have beep codes for the alarms your getting? What does the UPS battery test say?
 
Yeah, I've seen batteries show correct Voltage & then fail to deliver Current sufficiently.
It especially happens with rechargeable ones, never seen it with an Alkaline.

I wanted to test their Current, but my meter would melt, unless I got another load in-line with it.

Don't forget, the local battery guy put two new ones in it on Monday morning, still nothing.
The manufacturer claimed that wasn't a good test, because they should have been charged for 8 hours before trying to turn it on.

I can't find a menu for a battery test in the manual, but there is supposed to be an indication right on the LCD if it thinks the batteries need to be replaced:

1661367510469.png


There is a display for battery remaining, & if I unplug it quickly drops.
It was doing that before, which is why I put a fresher battery in it, but that battery is currently back in my single-battery unit under my computer desk.
 
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Found the battery test button, the right-most button, held for two seconds.
Weird, it's not in the manual. Now shows 100% battery & 120 minutes run-time on battery, hmm.

add:

Do you have beep codes for the alarms your getting?
I forgot to add there is no breakdown of what the beeps mean in the manual, but it does have this:

1661371920526.png


It cycles through various displays between beeps, but none indicate a fault.

Final decision, the refurb will go in service & I'll toss this one in a closet for a spare, for parts or even temporary service.
It started with the beeping again & no amount of pressing the Mute button does any good, which is probably what happened the other morning & just got frustrated with it.
 
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Ok, well yes, it does sound like the unit rather than the batteries is actually faulty.. .does happen.
 
Weird intermittent faults are the worst, & best avoided if possible.
Luckily in this case, I have the choice to bin it, Ha!
 
Refurbed unit in service now with fresh batteries from Vietnam:

PXL_20220827_145914102.jpg


The Duracell I used to buy are made in China & they want almost $100 for a set of two now.
As expected the new ones show a runtime of over 70 minutes, which stays put, while the old ones were starting under 60 & quickly dropping.
 
I'd given up on the manufacturer, but they sent me an eMail today asking if I had resolved the issue or needed more help.
I was tempted to send them a photo of the original unit that's in pieces in a box now, HA!
but just told them I bought another & it was NOT the batteries
 
A lot of these UPS need to be re-calibrated when the batteries are replaced, they can misbehave like you described if the batteries are not behaving as expected and changing some old ones for new ones will change the behaviour significantly.

The manufacturer should have told you a correct procedure when changing the batteries which will cause the controller to re-calibrate, it's in the paper manual for my Eaton one.
 
I looked in the manual, nothing.
It wouldn't turn on at all for a while, then after a few days riding around in my vehicle it seemed fine again, but wasn't, because it still did the incessant beeping as if there was poor Power input, but there wasn't.
I would not be surprised if the manufacturer has a calibration procedure they wouldn't tell me about, because they first had to rule out the batteries 44 different ways. That's probably the main reason customers contact them, because they're trying to use flat batteries.

I'm reminded of the trouble call that was being shared around about a customer who couldn't get their computer to work & at the end of the call the customer revealed that their Power was out, HA!
 

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