[Nut-upsuser] [Bug 215389] [NEW] No battery charge percentage on belkin usb avr

[Carlos Rodrigues]

On Fri, Apr 11, 2008 at 8:02 PM, Arnaud Quette <aquette.dev at gmail.com> wrote:
> 2008/4/10, David Erosa <david.erosa at gmail.com>:
>  >  After updating to last nut package (2.2.1-2.1ubuntu6), the megatec_usb
>  >  driver seems to be working, except for the charge percentage:
[...]
>  >  F => FAILED [short read]
>  >  F detail: (0 bytes) =>
>  >  Cannot calculate charge percentage for this UPS. <-****************
[...]
>  >  So I tried the svn version (as today, revision 143) and the result is:
>  >  F => OK [#230.0 002 12.00 50.0]
>  >  12.0V battery, interval [9.7V, 13.7V]. <-----****************
>  >  Done setting up the UPS.

The first snippet shows that the driver couldn't get the ratings from
the UPS, and without those values there's no way to calculate the
charge percentage. There have been some improvements in reliability
while talking to the UPS, so maybe that's why the newer version works.

You can always use the battvolts option though, like Arnaud said. And
it looks like you need to use it because the calculated percentage
doesn't look correct (assuming the UPS is fully charged). The thing
is, for a given nominal battery voltage, different models from
different vendors behave differently, and there is no way to tell them
apart to ajust the calculation.

-- 
Carlos Rodrigues