Abstract: In present market,most motor protectors can not realize data collecting,data processing,data communication and output control independently.It must depend on computer to realize measurement and controlling which will be interrupted once the computer malfunctions.According to these characteristics,the system selects MSP430F247 microcontroller from TI company as MCU of intelligent module and an intelligent motor protector is designed,which can realize data collecting,data processing,data communication and output control independently.It can not only measure the speed and steering of motor with rotary encoder,but also realize the overcurrent protection of motor and unbalanced protection of three-phase current.

Key words: MSP430F247 microcontroller, rotary encoder, data collecting, data communication, intelligent motor protector