Methods to Improve Modbus Communication Speed in Delta Servo Systems

 In PLC applications, communication with servos often uses RS-232/485 and the Modbus protocol. However, this can limit responsiveness. Here are some methods to speed up communication using Delta A2 servo as an example:

1. Increase Baud Rate (P3-01.X)

   • Higher baud rates reduce transmission time per bit. Ensure short, well-isolated cabling to minimize errors.

2. Switch from ASCII to RTU (P3-02)

   • RTU mode uses fewer bits per packet compared to ASCII, effectively halving transmission time.

3. Utilize Mapping Parameters

   • Use P0-25 to P0-32 to map non-continuous addresses, reducing the number of communications required.

4. Synchronize with PLC Scan

   • Synchronize data refresh with PLC scan cycles to maintain consistent communication and prevent logic errors.

These techniques enhance the efficiency and responsiveness of Modbus communication in Delta servo systems, making it competitive with more complex networks like CAN bus or EtherCAT for small systems.