N-Tron ESERV-M12T, User Manual

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Appendices ESERV-M12T Modbus Gateway
58 ESERV-M12T (Rev. 1210)
APPENDIX D: CONNECTOR PINOUT
ESERV-M12T SERIAL PORT PINOUTS
Terminal RS-232
RS-422/RS-485 4-
Wire
RS-485 2-Wire
A RTS (Output) TXA(-) DATA A(-)
B TD (Output) TXB(+) DATA B(+)
C CTS (Input) RXA(-) ---
D RD (Input) RXB(+) ---
E GND GND GND
In the RS-422 mode, TX lines are outputs and RX lines are inputs. Connect the Modbus gateway TXB(+) line to the
RXB(+) line of the Modbus network, and the Modbus gateway TXA(-) to the RXA(-) of the Modbus network.
Ground is signal ground and provides a common mode reference for the RS-422 Receiver and Transmitters.