CDE360 Vector Control AC Drive Chapter 8 Communication Protocol
8.5 Functions of Protocol
The main function of the MODBUS protocol is to read, write the AC drive function code parameters
and non functional code parameters, different parameters determine different operation request.
The AC drive MODBUS protocol support command code as shown in table 2.
Table 8- 2 Function code illustration
Function code
（
HEX
）
Description
03H
Read AC drive function code or status word
06H
Change AC drive function code or control word
The AC drive function code parameters and non functional code parameters are mapped to Modbus
read write registers. The read and write attribute and the range of function code parameters
(maximum, minimum) observe the instructions of AC drive using manual. Non functional code
parameters including the run command, running state, run / stop parameters and fault information.
Communication Address of Function Parameters of the AC Drive
The converter function code parameters, control parameters and monitor parameters are
mapped to Modbus read write registers.
The function code parameter attribute and range can reference the user manual instructions
follow the frequency converter.
The group code of the function code mapped to high byte of Modbus register, and the internal
group index mapped to low byte of Modbus register.
The control parameters and monitor parameters are also function code group.
Function code group number and the mapping register address high byte correspondence are listed
in the following table:
