Generally you can assume the output values from sensor are around 3.3V at full scale and calculate directly the factors :
30V / 3.3 = 9.9 for VoltageFactor
90A / 3.3 = 27.27 for CurrentFactor
Voltage calibration is pretty easy without any previous data:
- Apply power
- Check voltage displayed in PFD
- Check real voltage value measured
- Increase / decrease Voltage factor
- Find the right value so both value displayed are the same.
For current measurement you will need to set approximate value and quiet current value adjusting the "CurrentZero", do a flight and check if the energy consumed matches the capacity added after battery charging.
Finally apply a coefficient to the CurrentFactor value according to the board/charger measurement ratio for fine adjustment.