[Nut-upsdev] Mustek PowerMust 848

[Marian Ciobanu]

> Mark the note about BATTERY CHARGE in the blazer man page. What you're
> attempting may appear to work for *one* load condition and the battery
> capacity you have now, but it *will* fail if the either load or
> battery capacity changes. Please familiarize yourself with the Peukert
> equation before attempting to 'improve' the calculation and find that
> this can't be done with the values that are reported by the UPS.

The blazer manual warns that using a linear approximation based on
voltage is quite inaccurate. So I think it is improvable. True, it's not
going to get very accurate, but is the current implementation the best
that can possibly be done? The UPS reports a "load", which is related to
current. I think it should be used when determining a charge. (A
calibration program would be nice too.)

Anyway, I have to run my experiments first. My goal is to have a variable
that goes from 100, when the battery is fully charged and the AC power is
lost, to 0, when the UPS starts to warn that it has reached the "low
battery" level. This should work for dynamic loads, decreasing faster as
the load increases. If I make significant progress, I'll report back
sometime next week.


------------------

>> Did I misunderstand something in the manual?
>
> Absolutely. See what is written under EXTRA ARGUMENTS.

Well, the BATTERY CHARGE section doesn't mention
"default.battery.voltage.high", only "battery.voltage.high". True, you
find the "default" thing in EXTRA ARGUMENTS, but why look there if
BATTERY CHARGE tells you clearly what to do and if you are a simple
user, and not the developer who knows that there are "default" variables,
which are treated slightly differently from the rest. I think it would
be a good idea to replace "battery.voltage.high" with
"default.battery.voltage.high" in blazer's manual.

Best regards,
  Ciobi