Read supply voltage of remote device

Hello,

i want to ask, how is it possible to read the right board supply voltage of a remote xbee device with python.

The supply voltage read with %V is 0,02 V above the right supply voltage at the VCC pin of the module.

Because of this failure my temperature value of my remote xbee device with the ADC isn’t right. The module is powered by a battery and a grove development board. Powered with USB there is the same failure.