<div dir="auto">Hello.<div dir="auto"><br></div><div dir="auto">I sometimes encountered batteries that were ok, but at times one of the cells would develop a random short/open, therefore reducing the real capacity even if voltage reading was ok. In the absence of a battery load tester i would suggest running multiple tests with a load (car headlight bulb or similar) on the battery outside the ups. This is to eliminate the suspicion of a software or UPS unit fault.</div><div dir="auto"><br></div><div dir="auto">Alex. </div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, 27 Jan 2020, 02:53 Manuel Wolfshant, <<a href="mailto:wolfy@nobugconsulting.ro">wolfy@nobugconsulting.ro</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div>
<div>On 1/25/20 10:53 AM, Georgi D. Sotirov
wrote:<br>
</div>
<blockquote type="cite">
<div align="justify">OK, so yesterday evening I done a real test
cutting of the power to the UPS. And it went good... the UPS
supported my server for 28:50 minutes (i.e. the expected runtime
with this load), before forcing shutdown. The batteries could
still hold as charge was 30 % with about 15 minutes run time.
And the UPS did hold for another full 10 minutes before powering
off. These are the relevant lines from /var/log/ups:<br>
<br>
<font face="Courier New, Courier, monospace">20200124 201318 32
0.0 12 [OB] NA 0.0<br>
<font color="#ff0000">20200124 201323 30 0.0 13 [ALARM OB LB]
NA 0.0</font><br>
20200124 201328 30 0.0 13 [FSD ALARM OB LB] NA 0.0<br>
20200124 201333 30 0.0 13 [FSD ALARM OB LB] NA 0.0<br>
20200124 201338 30 0.0 13 [FSD ALARM OB LB] NA 0.0<br>
20200124 201340 30 0.0 13 [FSD ALARM OB LB] NA 0.0</font><br>
</div>
</blockquote>
<p>that looks perfectly fine<br>
</p>
<p><br>
</p>
<blockquote type="cite">
<div align="justify"> <br>
The server was shutdown properly, but for some reason it did not
power off. I saw an error from <font face="Courier New,
Courier, monospace">umount</font> about busy file system, but
I'm sure this doesn't always happen.<br>
</div>
</blockquote>
<p>the error is related to your linux system, not to nut<br>
</p>
<p><br>
</p>
<blockquote type="cite">
<div align="justify"> <br>
With everything powered off, I extracted the original batteries
to check them and measure the voltage. The batteries are Leoch
DJW12-9.0 with one of them at 12.57 V and the other at 12.64 V
(measured without load after the discharge).<br>
</div>
</blockquote>
<p>That's... surprisingly well, assuming your multimeter indicates
correct values. I would have expected values well below 12V</p>
<p><br>
</p>
<p><br>
</p>
<blockquote type="cite">
<div align="justify"> <br>
And this morning there was again a short power failure (not more
than 30 minutes, because the router connected to the battery
power from the UPS did hold up). With batteries charged up to
91% the UPS supported the server for just 07:10 minutes and
forced shutdown with 69% battery charge and over 20 minutes of
run time...<br>
<br>
<font face="Courier New, Courier, monospace">20200125 021123 70
0.0 16 [OB] NA 0.0<br>
<font color="#ff0000">20200125 021128 69 0.0 16 [FSD ALARM OB
LB] NA 0.0</font><br>
20200125 021133 69 0.0 16 [FSD ALARM OB LB] NA 0.0<br>
20200125 021138 69 0.0 16 [FSD ALARM OB LB] NA 0.0<br>
20200125 021143 69 0.0 16 [FSD ALARM OB LB] NA 0.0<br>
20200125 021148 69 0.0 16 [FSD ALARM OB LB] NA 0.0<br>
20200125 021150 69 0.0 16 [FSD ALARM OB LB] NA 0.0</font><br>
<br>
So, it seems to me that my UPS forces shutdown pretty randomly.
Why the UPS is not waiting for the preset low battery charge
value of 15%? What is actually driving this FSD ALARM and LB
signal when batteries for sure could hold up more?</div>
</blockquote>
<p><br>
</p>
<p>Can you please show us all the configuration files ? I can only
suspect that there is something wrong there because (from a
hardware point of view) the UPS behaves very very well, according
to your tests and logs.<br>
</p>
<p><br>
</p>
</div>
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