Protocol Content; Application Styles; Chapter Twelve Appendix; Appendix One: Rs485 Communication Protocol - Veichi Electric AC60 series Manual

Appendix one: RS485 communication protocol

1. Communication protocol
The AC60 series frequency inverter can select the RS485 communication
interface. The international standard ModBus communication protocol is
adopted for master-slave communication. The consumer can carry out
centralized control by PC/PLC, upper machine, main station frequency inverter
etc (Setting of the frequency inverter control command, running frequency,
relative function parameters modification, frequency inverter working state
and malfunction information monitoring etc.) to adapt to the special
application requirements.

2. Protocol content

This ModBus serial communication protocol defines asynchronous transfer
information content and formats used in the serial communication. Including:
host machine roll poling and broadcasting、slave machine responsive format;
Content of the data frame of host machine organizes including: slave machine
address (or the broadcast address), demand to act function code, back to data
and error checking etc. Slave machines responding adopts the identical
structure. The contents including: action being affirmed, back to data and
error checking and so on. During the period of slave machine receiving frame
If mistakes happen, or the action that the host machine demands can not be
accomplished, it will organize one frame of malfunction information as
response and feedback to host machine.

3. Application styles

AC60 series frequency inverter is connected to " single host and many
slave machines"control network with RS232/RS485 master line.
4. Bus configuration
(1)Interface mode

Chapter twelve Appendix

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