Since the rotor of the alternator is driven by the engine through the belt, and the speed ratio of the engine to the alternator is 1.7 to 3, the range of the speed of the alternator rotor is very large, which will cause the output voltage of the generator to occur. Large changes can not meet the working requirements of automotive electrical equipment. In order to meet the constant voltage requirements of electrical equipment, the alternator must be equipped with a voltage regulator so that its output voltage remains substantially constant under all operating conditions of the engine. Vacuum Ground Sewage Discharging System Ground Sewage Discharging System,Semi Vacuum Drainage System,Indoor Vacuum Drainage System,Outdoor Vacuum Drainage System CRRC SHANDONG CO., LTD. , https://www.crrcsd.com