[Nut-upsuser] Fwd: Cyberpower usbhid-ups wrong battery voltage

davor emard davoremard at gmail.com
Wed Apr 2 09:19:58 UTC 2008

I think the firmware is broken as it didn't apply correction
factor/offset to get volts in the HID diescriptors.

I haven't scanned the protocol - but *I think* in the HID
report descriptors contains fields for measured value of
the battery voltage and the physical unit (V, mV) that
describes the value. Unit can be a physical unit but also
some undimensioned value (that may need correction
factor and offset)

I wonder is the cyberpower really outputting volts wrong
or does it report an undimensioned value which in the
upsc gets interpreted as volts although it is not true volt
measure report

Best regards, Davor

On 4/2/08, Arjen de Korte <nut+users at de-korte.org> wrote:
> > I have cyberpower value 800E connected via usb.
> > In the status battery voltage is too high 20V - 21V
> > while measurement at the battery terminals gives 13.6V
> This value is reported by the UPS in 'UPS.PowerSummary.Voltage' and we
> display it 'as is'. It could be that the measuring circuit in your UPS is
> broken, or that all similar models require a correction factor / offset.
> There is really nothing we can do about the device reporting 'wrong
> values' at this time.
> --
> Eindhoven - The Netherlands
> Key fingerprint - 66 4E 03 2C 9D B5 CB 9B  7A FE 7E C1 EE 88 BC 57

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