DFC series single-se servo amplifier is an accessory of combined instrument in DDZ type electric unit, which receives the nsmitting and regulating and manual control r units, automatically regulates the operating mechanism and completes the regulating task by cooperating with the electric actuating mechanism. It is widely used in the regulating and control system of automation in the process of production in power plant, chemical industry, petroleum, metallurgy, mining and light industry when it works with other units of DDZ-type meters.