MODBUS Protocol 95
Appendix II: MODBUS Protocol Specification
1. Communication setting
F4.00＝X1XX, select MODBUS RTU protocol；
Note: X represents that the bit is arbitrary number.
2. Communication function
Complete communication between upper machine and inverter, including
sending operation command to inverter, setting running frequency, rewriting
function code parameter, reading running status of inverter, monitoring parameter,
fault message and function code parameter.
3. Protocol format
MODBUS RTU format
ADU
＞3.5
character
transmission
interval
Slave
machine
address
Function
code
Data
CRC
check
＞3.5
character
transmission
interval
PDU
1.1 Interpretation of protocol format
1. Slave address
0 is broadcast address and the slave address can be set as 1-30.
2. PDU part
(1) Function code 03: Read functional parameters, running status, monitoring
parameter and fault message of multiple inverters, and 6 inverter parameters
with continuous address at most in one time.
Sent by main machine:
PDU PART
03
Data length (Byte) 1
Register initial address
High
Low
1
1
Number of registers
High
Low
1
1
E500 Series Universal Low-Power Inverter
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