Termination Resistor Setting; Connection Diagram - Mitsubishi MELSEC iQ-F FX5 User Manual

Termination resistor setting

Make sure to provide a termination resistor at both ends of the wire.
The built-in RS-485 port, FX5-485-BD and FX5-485ADP have a built-in termination resistor.
Set the termination resistor selector switch as below.
Wiring
Two-pair wiring
One-pair wiring
■FX5U CPU module built-in RS-485 port
■FX5-485-BD

Connection diagram

■One-pair wiring
Built-in RS-485 port
FX5-485-BD
FX5-485ADP
SDA
(TXD+)
SDB
(TXD-)
RDA
(RXD+)
*2
RDB
(RXD-)
SG
*1 Make sure to perform Class-D grounding on the shield of the twisted pair cable to be connected.
*2 Set the termination resistor selector switch to 110 Ω
*3 Set the termination resistor selector switch to 330 Ω
3 PARALLEL LINK FUNCTION
56
3.5 Wiring
Termination
resistor selector
switch
Termination
resistor
selector switch
Built-in RS-485 port
FX5-485-BD
FX5-485ADP
SDA
(TXD+)
SDB
(TXD-)
RDA
(RXD+)
RDB
(RXD-)
SG
Class-D grounding *1
Termination resistor selector switch
330 Ω
110 Ω
■FX5UC CPU module built-in RS-485 port
■FX5-485ADP
■Two-pair wiring
Built-in RS-485 port
FX5-485-BD
FX5-485ADP
SDA
(TXD+)
*3
SDB
(TXD-)
RDA
(RXD+)
*2 *3
RDB
(RXD-)
SG
Termination
resistor selector
switch
Termination
resistor selector
switch
Built-in RS-485 port
FX5-485-BD
FX5-485ADP
SDA
(TXD+)
SDB
(TXD-)
RDA
(RXD+)
RDB
(RXD-)
SG
Class-D grounding *1
*3
*3