ON
1234
7
z Precautions when setting
Even if the Master’s protocol is changed during communication between Master and slaves (LS
inverters), the communication is resumed automatically in case of adjusting the DIP switch on the
option card in accordance with the master’s protocol.
5.
5.1.
5.1.1.
COMMUNICATION PROTOCOL
z Use RS485 protocol (for LS only) and Modbus-RTU protocol. RS485 and Modbus-RTU protocol are
Open protocol. For more information, contact LS distributor.
z Computer or other host acts as Master while inverters act as slaves. The inverter responds to
Read/Write command from Master.
RS485 Protocol
Basic format
z Command message (Request):
ENQ Inverter No. CMD Data SUM EOT
1 byte 2 byte 1 byte n byte 2 byte 1 byte
z Normal response (Acknowledge Response):
ACK Inverter No. CMD Data SUM EOT
1 byte 2 byte 1 byte n * 4 byte 2 byte 1 byte
z Negative response (Negative Acknowledge Response):
NAK Inverter No. CMD Error code SUM EOT
1 byte 2 byte 1 byte 2 byte 2 byte 1 byte
z Description:
* Request starts with “ENQ” and ends with “EOT”.
* Acknowledge Response starts with “ACK” and ends with “EOT”.
* Negative Acknowledge Response starts with “NAK” and ends with “EOT”.
* “Inverter Number” represents the number of Inverters and indicates in 2 byte ASCII-HEX.
(ASCII-HEX: Hexadecimal consists of ‘0’ ~ ‘9’, ‘A’ ~ ‘F)
* CMD: Capital letter (“IF Error” when small letter is used.)
Character ASCII-HEX Command
‘R’ 52h Read
‘W’ 57h Write
‘X’ 58h Request for Monitor Register
‘Y’ 59h Action for Monitor Register
Æ Modbus-RTU protocol selection
To Next Page
Loading...