BMS error – State of Charge is shown incorrectly

Battery management determines the State of Charge (how full is my battery?) by calculation. If this representation is incorrect, there could be a number of different causes:

  • The State of Charge is largely determined and calculated by the current sensor in the battery system. So it is very important that this measurement is accurate. To do this, check the following settings:
    • Does the current sensor indicate a negative value while discharging (driving)? If this is a positive value, the direction can be reversed from the current sensor in the BMS control panel at Configuration/general –> ” reverse direction”
    • Does the current sensor indicate a positive value while charging? –> if not the case then the current sensor is not mounted in the correct position. The current sensor must measure both the current going into and out of the battery system
    • Does the current sensor corretly indicates “0” amps if there are no consumers at the high voltage battery? –> turn off all consumers by pressing the emergency stop, for example, and calibrate the value in the BMS control panel at Configuration/general –> ” Reset current to 0″
  • Is the correct battery capacity (Ah) set in the BMS control panel at configure/SOH –> cell capacity. You can check this set value in the BMS control panel at Status / SOC/SOC –> capacity. Here the capacity in Coulomb is shown. Dividing this value by 3600 should indicate the battery capacity in Ah.
  • Has the package already been charged 100% once? –> Fully charge the battery system until it indicates ” charging finished.” At this moment the State of Charge is calibrated to 100%

Also watch our video for instuctions: