MATRIX 400™ REFERENCE MANUAL
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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 M16 19-pin connector are used for RS485 full-duplex
communication:
Pin Name Function
M TX+ RS485 Transmit Data (+)
N TX- RS485 Transmit Data (-)
U RX+ RS485 Receive Data (+)
T RX- RS485 Receive Data (-)
L GND Ground
MATRI
X
GND
RX+
RX-
TX-
TX+
USER INTERFACE
TX485
RX485
SHIELD
Reference Ground
L
U
T
N
M+
K
-
+
-
Earth Ground Earth Ground
Chassis
Figure 78 - 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.
MATRI
X
GND
RX+
RX-
TX-
TX+
USER INTERFACE
RX485
SHIELD
Reference Ground
L
U
T
N
M+
K
-
Earth Ground Earth Ground
Chassis
Figure 79 - RS485 Full-duplex Connections using Only TX Signals