First, let's take a summary look at Parts 1 through 9: We explained that electrcon current is the movement of negatively charged electrons through a completed circuit (when switch CLOSED). Electrons leave the negative terminal of the voltage source, travel through the circuit and return to the positive terminal of the same voltage source. This concept is important because the battery and the generator are connected in a parallel circuit arrangement. If the battery supplies electron current (engine OFF), the electrons leave the -BATT terminal and return to the +BATT. If the generator supplies electron current (engine RUN), the electrons leave the -GEN terminal and return to +GEN. For the full summary and Part 10, click here for the PDF.