The modern industry equipment uses PLC to take the primary control circuit massively, PLC takes the entire equipment's core part, its software has forgiven the technique of production, the control logic, the equipment data, the processing parameter and the information communication and so on important content, the frequency conversion velocity modulation technology is one kind changes motor's power supply frequency to pick serves the motor velocity modulation purpose the technology. Uses PLC and the frequency changer may realize the multistage fast control, this article unifies the electric motor five sections of fast controls the applications, elaborated PLC and the frequency changer realize the multistage fast in the factory on conveyer belt's application.
[key word] Frequency changer Multistage fast Parameter
