7300CV MODBUS COMMUNICATION PROTOCOL
File No. :PC-CV-08
Version : 1.A
Page :
2/34
1. Communication Data Frame
7300CV series inverter can be communication controlled by the PC or other controller with the
communication protocol, Modbus ASCII Mode & Mode RTU, RS485 or RS232.
Frame length maximum 80 bytes
1.1 Hardware installation
Slave 7300CV
Station 01
Slave 7300CV
Station 02
Slave 7300CV
Station 03
Slave 7300CV
Station FE
Controller
(PLC / HMI or
PC )
Option Card
Option Card
Option Card
Option Card
RS-485
Interface
RSA RSB
RSA
RSB
RSA
RSB
RSA
RSB
Response
Request
** The network is terminated at each end with an external terminating resistor (120 ohm, 1/4 watt).
1.2 Data format frame FOR ASCII MODE
STX(3AH)
Start Bit = 3AH
Address Hi
Address Lo
Communication Address(Station):
2-digit ASCII Code
Function Hi
Function Lo
Function Code (command):
2-digit ASCII Code
Command Start Address
Command Start Address
Command Start Address
Command Start Address
Command Start byte:
4-digit ASCII Code
Data length
Data length
Data length
Data length
The length of the command:
4-digit ASCII Code
LRC Check Hi
LRC Check Lo
LRC Check Code:
2-digit ASCII Code
END Hi
END Lo
End Byte:
END Hi=CR(0DH),END Li = LF(0AH)
Data format frame FOR RTU MODE
MASTER (PLC etc.) send request to SLAVE, whereas SLAVE response to MASTER. The signal
receiving is illustrated here.
120
Ω
1/4w
120
Ω
1/4w
