[Nut-upsuser] ups.test.result meaning

Gene Heskett gheskett at shentel.net
Sun Nov 1 08:05:54 GMT 2020

On Saturday 31 October 2020 21:59:32 Rick Dicaire wrote:

> > > battery.voltage: 16.0
> >
> > At that voltage, 5 of the 12 cells are shorted
> >
> > > output.voltage: 138.0
> >
> > too high by about 15 volts
> >
> > Wow!  That battery is beyond toasted, shoulda been replaced months
> > ago. And the output voltage is a bit much if its truthfull.
> Thanks for the response Gene!
> I've ordered a replacement unit.
> I'm not sure about the output voltage readings, I have four CyberPower
> CP1500AVRLCDa UPSs and they all show 136-139v output.
> My CyberPower OR1500LCDMRM1U reports 124v.
> I still don't know what triggers the warning in the test though...
The voltage, 16 volts,  is well below a 12 cell, 2 battery voltages LB 
trigger point.  A LA battery capacity vs voltage is not a linear 
correlation. Fully charged, it should be showing about 26.5 to maybe 
even 27 volts. A 10% charge s/b seen at around 24 volts.  Yours is down 
to 16 volts, and its working like crazy trying to charge a 12 cell LA 
battery with 5 shorted cells. Which will quickly result in more shorted 
cells because of the overcharge of the remaining good cells. I'd take it 
out of service until replacement batteries arrive.

I once tried to use 4 wet batteries in an older NCR UPS, but found it 
charger set for 56 volts and the batteries were boiling. So I found the 
adjuster and turned it down to 52.5 as I replaced all 4 batteries again. 
It still cooked the next set of batteries in around 90 days. I recycled 
it, replaced it with a belkin but it wasn't adjustable and fried a set 
of gel-cells a year. Replaced it with another belkin which treated its 
batteries better, 3 years a set, now there an APC in that circuit I can 
use as a footstool. Been there about 2 years and holding up well so far, 
but its taken the ups people 25 years to learn how to deal with gelcell 
batteries. They don't deal with overcharge as well as std wet batteries 
which you can replace the gassed away water.

I am a C.E.T. a retired broadcast Chief Engineer and have experience with 
both wet and gel-cell. I took over a transmitter site for Nebraska ETV 
in about 1970, and inherited a well cooked set of 220 AH truck batteries 
to start the 250kw Cummins stdby generator. One of the first things I 
had to do was go get a pair of fresh batteries because they would not 
turn that 335 over to start it.  Had a battery charger that was boiling 
the new batteries, so I raised the resistor in series with the charger, 
and kept raising it, until the trickle charge rate was down to about 10 
milliamps which still kept those new batteries at a 1.265 Specific 
Gravity, needing about a pint of distilled water a year to restore 
liquid levels. 7 years later when I went down the road to a new office 
door and lots more sheckles, those now old batteries still looked new, 
and would still turn that 335 comealong wrong side out starting it. From 
signal to start to useable power output was under 2 seconds. It was 
firing and running well enough to kick the starter bendix back out in 
half a turn.

I don't think any of the UPS makers have an engineer with that sort of 
long term experience with lead acid batteries. They are burning up the 
gel-cells from over charging. They look at the battery sales as part of 
their cash cow and will use every trick they can to raise the ratings.

But now I'm officially a retired old fart at 86, so what do I know? ;-)

Cheers, Gene Heskett
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page <http://geneslinuxbox.net:6309/gene>

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