Mitsubishi Electric F700 Instruction Manual page 167

Communication operation and setting
(4) RS-485 terminal wiring method
Wiring of one RS-485 computer and one inverter
Wiring of one RS-485 computer and "n" inverters (several inverters)
Computer
RDA
RDB
SDA
SDB
RSA
RSB
CSA
CSB
SG
FG
*1 Make connections in accordance with the manual of the computer used.
Fully check the terminal numbers of the computer since they change with the model.
*2 For the inverter farthest from the computer, set the terminating resistor switch to ON (100
REMARKS
For branching, connect the wires as shown below.
To computer send
To computer receive
To computer ground
(5) 2-wire type connection
If the computer is 2-wire type, pass wires across reception terminals and transmission terminals of the RS-485
terminal to enable 2-wire type connection with the inverter.
REMARKS
Create a program so that transmission is disabled (receiving state) when the computer is not sending and reception is
disabled (sending state) during sending to prevent the computer from receiving its own data.
160
Computer
RDA
RDB
SDA
SDB
RSA
RSB
CSA
CSB
SG
FG
*1
SG SG
Station 0
- - -
+ + + +
RXD
+ - + -
+ - +
TXD
SG SG
VCC
Computer
Transmission
enable
Reception
enable
SG
*2
*1
SG
SG SG
Station 1
+ - + - + -
+
RXD
To next inverter
To receive terminal
+ - + - + - +
TXD
To next inverter
To send terminal
SG SG
VCC
To next inverter
To earth (ground)
terminal
Inverter
TXD+
TXD-
RXD+
RXD-
Pass a wire
SG
*2
SG
Station n
Ω
side).