[Nut-upsdev] Tripplite Smart1500SLT configuration?

[Arjen de Korte]

>>> Is that normal behavior? At what point does the UPS get shut off to
>>> protect the battery from total discharge? I'll confess I am fairly
>>> ignorant about what's supposed to happen here, but I understand you
>>> don't want to let these batteries go completely dead.
>> I suggest that you first read the INSTALL document that came with NUT.
>> If
>> anything is not clear after reading this (and the other documentation it
>> references), come back to the mailinglist. I don't reply to messages
>> sent
>> to me in private, unless a consulting fee is involved.
>>
> My humble apologies - I hit reply, expecting that it would go to the
> list (most of the lists I subscribe to are set up that way) and didn't
> notice it was addressed to an individual. So sorry!
>
> I actually have read trunk/INSTALL, trunk/README, most of the files in
> trunk/docs. I think I have a pretty good idea  how it works, but I'm not
> entirely sure about this one point about whether or not the UPS can be
> instructed to power itself off to spare the battery from going totally
> dead. This is important to me because I live up in the mountains and in
> the winter we lose power several times every winter for longer than most
> UPS's can stay up. Their purpose is to keep things up over the glitches
> and short outages.

You typically need to modify the system 'halt' script. How this works is
mentioned in the last paragraph of the INSTALL document or (more in
detail) the 'docs/shutdown.txt' document. Some distributions will provides
hooks for that (openSUSE for instance), on others you may need to do that
yourself. From looking at the 'upsc' output, I'm fairly certain that your
UPS supports shutting it down. On some systems, you may need to add '-u
root' to the shutdown command line, if udev/hotplugging is no longer
available at the time 'upsdrvctl shutdown' runs.

[...]

> Thank you for straightening me out on that one. I guess I am surprised
> that that this UPS is showing a ups.load=12%. When I put the same load
> on the other UPS I have (an APC 1500) it shows about an 80 Watt
> continuous load. I thought it was possible there might be a scale factor
> difference still in play.

The 'ups.load' parameter reports the apparent load of the UPS, so for a
1500 VA rating UPS, this would boil down to about 180 VA. This may (or may
not be) equal to a load of 80 W (note the difference between the apparent
and real power). You also have to understand that both resolution and
accuracy of almost all values reported is (too) low and many times more
driver by marketing people than a useable feature.

"A UPS is not a measuring instrument."

Best regards, Arjen
-- 
Eindhoven - The Netherlands
Key fingerprint - 66 4E 03 2C 9D B5 CB 9B  7A FE 7E C1 EE 88 BC 57