External Wiring With Rs-422/485 Interface; Rs-422/485 Terminal Block Specifications - Mitsubishi Melsec-L Series User Manual

6.3 External Wiring with RS-422/485 Interface

6.3.1 RS-422/485 terminal block specifications

SG
(FG)
(FG)
LJ71C24
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This section explains the specifications of RS-422/485 and how to connect them with
external devices.
The following shows the specifications of the RS-422 connector and RS-422/485
terminal block that connect to an external device.
SDA
Mnemonic
SDB
SDA
RDA
SDB
RDA
RDB
RDB
SG
FG
FG
(1) The following describes the control signals.
1) SDA, SDB signals
These are signals to send data from the C24 to the external device.
2) RDA, RDB signals
These are signals for the C24 to receive data from the external device.
(2) Terminating resistor
Connect the termination resistor referring section 6.3.3.
(3) Suitable crimp-on terminals
Use 1.25-3 for the solderless terminal to be attached on the terminal block.
Use the UL certified crimp-on terminal. For crimping the terminal, use the tools
recommended by the crimp-on terminal manufactures. Crimp-on terminals with
insulation sleeves cannot be used.
(4) Tightening torque
For details on the tightening torque for the RS-422/485 terminal block, refer to
Section 6.1.1.
Signal name
C24
Send data (+)
Send data (–)
Receive data (+)
Receive data (–)
Signal ground
Frame ground
Frame ground
6 SETTING AND WIRING
Signal direction
External device
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