The SmartAP PDB pinout diagram is shown below. The larger pads in the rear side are intended for the main battery connection. Up to 4 independent batteries can be connected using the thick wires (e.g. 8-10 AWG). The thick wires are essential to be able to handle high current loads. Both top and bottom, and left and right sides have pads for a ESC power supply connection. Therefore, up to 12 ESCs can be connected.