Mitsubishi QJ71C24N - RS-422;485 Interface Specifications; RS-422;485 Terminal Block Specifications

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MELSEC-Q
3 SPECIFICATIONS
3.3 RS-422/485 Interface Specifications
The following shows the RS-422/485 interface specification.
3.3.1 RS-422/485 terminal block specifications
The following shows the specifications of the RS-422 connector and RS-422/485
terminal block that connect to an external device.
Signal
abbreviation
Signal name
Signal direction
C24
External
device
SDA
SDB
RDA
RDB
SG
FG
FG
Send data (+)
Send data (–)
Receive data (+)
Receive data (–)
Signal ground
Frame ground
Frame ground
SG
SDA
SDB
RDA
RDB
SG
RDB
RDA
SDB
(FG)
SDA
QJ71C24N-R4
QJ71C24N
QJ71C24
(FG)
(FG)
(1) The following describes the control signals.
1) SDA, SDB signals
These are signals to send data from the Q series C24 to the external
device.
2) RDA, RDB signals
These are signals for the Q series C24 to receive data from the external
device.
(2) Terminating resistor
Connect the termination resistor according to section 4.2.2.
(3) Terminal
(a) Terminal block (QJ71C24N)
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 crimp-on terminal manufacturers. Crimp-on
terminals with insulation sleeves cannot be used.
(b) Plug-in socket block (QJ71C24N-R4)
Remove the shielded part of the cable and directly connect the cable to the
plug-in socket block.
Use the plate terminal (supplied with the product) to connect the braided
shield wire to the FG terminal on the plug-in socket block. (Refer to Section
4.4.)
(4) Tightening torque
For details on the tightening torque for the RS-422/485 terminal block, refer to
Section 4.1.