Instruction manual

25-PIN CABLE ELECTRICAL CONNECTIONS
63
5
5.4.2 RS485 Full-Duplex Interface
The RS485 full-duplex (5 wires + shield) interface is used for non-polled communication
protocols in point-to-point connections over longer distances (max 1200 m / 3940 ft) than
those acceptable for RS232 communications or in electrically noisy environments.
The following pins of the 25-pin connector are used for RS485 full-duplex communication:
Pin
Name
Function
2
TX+
RS485 Transmit Data (+)
3
RX+
RS485 Receive Data (+)
4
TX-
RS485 Transmit Data (-)
5
RX-
RS485 Receive Data (-)
7
GND
Ground
Matrix 210™
TX+
2
TX-
4
RX+
3
RX485
RX-
5
TX485
7
GND
GND
USER INTERFACE
+
-
+
-
Chassis
1
Figure 66 - RS485 Full-duplex Connections
NOTE
For applications that do not use RX485 signals, do not leave these lines
floating but connect them to GND as shown below.
Matrix 210™
TX+
2
TX-
4
RX+
3
RX485
RX-
5
7
GND
GND
USER INTERFACE
+
-
Chassis
1
Figure 67 - RS485 Full-duplex Connections using Only TX Signals