When the ignition key is in the position "ON ("ON"), current from the battery flows from the terminal "L" generator through the voltage regulator to the output "E", while the battery charging indicator lamp is on. When the engine is started, the output voltage increases as the generator speed increases. When the output voltage becomes greater than the voltage on the battery, then part of the energy generated by the generator goes to recharge the battery. At the same time, the output voltage "L" the potential difference between the battery and the output also increases "L" disappears, after which the battery charging control lamp goes out. If the output voltage goes out of regulation, the voltage regulator transistor changes the voltage in such a way that the generator voltage remains constant.