[Nut-upsuser] Incorrect 'low battery' detected with Back-UPS XS 1200 (usbhid-ups)

[Arjen de Korte]

> That is a lot more informative, thanks.
>
>> http://www.uno-code.com/files/nut.output.txt
>
> Ouch, this really sucks! It looks like the feature reports for this UPS
> are completely bogus and that we should only use the reports we get on the
> interrupt pipeline for this unit (which seem to be correct). That is not
> what we should expect, although we can probably work around that (even if
> I have no idea how yet).

Just for testing purposes *only* (this *will* break if you actually use
this to monitor your UPS), you could run

    /lib/nut/usbhid-ups -x pollfreq=86400 -a apc1

If you don't change any variables and also don't issue commands to your
UPS, you might be able to see some good values with 'upsc apc1 at localhost'.
Note that 'upsc' will require that 'upsd' is running, but you must *not*
run 'upsmon'.

This will basically increase the intervals for the periodic check for the
UPS feature reports to once a day, but it won't prevent the driver from
checking them completely. Also, when you change a variable or issue a
command, the feature reports will be requested anyway, so this doesn't
allow you to monitor the UPS, since it will initiate a shutdown
immediately then.

Best regards, Arjen