My less than a year old BMV-712 smart started showing .03 volts on fully charged batteries. The SOC is showing appropriate % reduction during use so I know that the proper voltage is getting to the display. Using the app on my phone I haven’t found a place to reset the voltage on the display. Any suggestions please?
If the shunt is still tracking SOC, then supply voltage must be getting to it.
Do you have an AUX voltage input on the shunt? If so, then try using that as the input.
Do you mean it shows 0.03V as the actual measurment or it shows an offset, for example 14.03V instead of 14.00V, so 0.03V offset?
First one sounds like an internal defect, since the voltage input is also used to power the unit. If that voltage would be missing then the BMV as a whole would be off. Likely a warranty situation.
Second situation can not be calibrated. BMVs are calibrated at the factory with an accuracy of 0.4%. You would need to calculate if the 0.03V are outside of that accuracy or not. If its within the accuracy, then thats ok, outside possibly also warranty situation.
SOC is tracked by current, thats what the shunt is for. Voltage is only used to reset the SOC to 100% on a full battery.