[Nut-upsuser] fake battery.charge on MGE UPS

[Jablonovsky Alexander]

I'm sorry about a wrong place to address, because my problem most likely
is in a hardware, not the NUT software. I had tried to contact the MGE
support team, but got no answer.

I have purchased the MGE Ellipse 650 UPS, and after testing it with the
Linux/NUT package (v. 2.0, mge-shut driver) found out that the
battery.charge indicator and related things (battery.lifetime, low
battery signal) don't function properly. Replacing the unit did not help.

After switching the UPS on battery.charge ALWAYS shows 85%, unrelated of
real battery status. Then, in the ON LINE state this variable slowly
counts up, and in the ON BATTERY state counts down (more faster). That's
all! If the battery have REALLY fully charged, the battery.charge
reaches 30% and triggers the LOW BATTERY signal in ~20 min, reaches 0%
in ~30 min, but the UPS can provide power, for example, above 1 hour.
If the battery have ran down before, the UPS can drop power after 2 min 
on battery run with battery.charge=78% and without LOW BATTERY warning! 
Sorry, but I want to have a UPS with battery monitoring, not a clock 
with alarm! This behavior makes the computer interface and software 
totally useless (except for the OL/OB status)!

With best regards,
Jabonovsky Alexander, the system administrator