Migration from RS-485 to EtherCAT for closed loop step motor drive

This paper explains a method for migration from RS-485 to EtherCAT for the closed loop step motor drive. Since realtime Ethernet is an alternative for the low speed fieldbus that uses RS-485 or CAN, the low speed fieldbus based legacy system (e.g. RS-485 based motor drive) also needs to support real-time Ethernet. Therefore, migration from the low speed fieldbus to real-time Ethernet becomes more important. In this paper, a migration method from RS-485 to EtherCAT is proposed for the closed loop step motor drive. While this paper explains the migration method from RS-485 to EtherCAT, the method can be applied to a range of migration types, from the low speed fieldbus to real-time Ethernet. The EtherCAT based closed loop step motor drive is developed and performance is analyzed and compared to the RS-485 and Mechatrolink ||| based motor drives.