Control commands
When F0-02 (command source) is selected as 2: communication control, the host computer can control the related
commands such as start and stop of the inverter through this communication address. The control commands are
defined as follows :
Inverter running status communication
address
Read Status Word Definition
2000H
1 : Forward operation
2 : Reverse operation
3 : Forward jog
4 : Reverse jog
5 : Free stop
6 : Decelerate to stop
7 : Fault reset
Communication settings
The communication setting value is mainly used for the given data when the frequency source, torque upper limit
source, V/F separation voltage source, PID given source, PID feedback source, etc. are selected as communication
given in the product. Its communication address is 1000H. When the host computer sets the communication address
value, its data range is -10000~10000, corresponding to the relative given value -100.00%~100.00
3. Modbus communication protocol
The product series inverter provides RS485 communication interface and supports Modbus-RTU slave
communication protocol. Users can realize centralized control through computer or PLC, set inverter running
commands, modify or read parameters, read inverter working status and fault information, etc. through this
communication protocol. The serial communication protocol defines the content and format of information transmitted
in serial communication. These include: host polling (or broadcast) format; host encoding method, including:
parameters required for action, transmission data and error checking, etc. The response of the slave also adopts the
same structure, including: action confirmation, return data and error checking, etc. If the slave has an error in receiving
the information, or cannot complete the action required by the master, it will organize a fault message as a response
and feed it back to the master .
4. Communication data structure
The Modbus-RTU protocol communication data format of the product series inverter is as follows, the inverter only
supports the reading or writing of Word-type parameters, and the corresponding communication read operation
command is 0x03 ; 10 , support byte or bit read and write operations :
Example 1: Read parameter d - 01 (set frequency) , query d- 01 to set the frequency parameter, and receive a return
value of 0 Hz
Modbus
address
Function
code
Parameter
number high
Parameter
Number low
High word
count
Word count
low
CRC
low
order
CRC
high
0x 01
0x03
0x70
0x01
0x00
0x01
0x81 0xF7
Answer:
Modbus address Function code Number of bytes Data high Data low
CRC
Low order
CRC
high
0x01
0x03
0x20
0x00
0x00
0xB8
0x 44
Example 2: Write the parameter F 0 -08 (maximum frequency of the inverter) to 20.0 0Hz , and the return setting value
is set successfully
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