User`s manual
MGate MB3000 User’s Manual Hardware: MB3270, MB3270I
7-5
Pin Assignments
DB9 (Male)
The MGate MB3000 uses DB9 (male) serial ports to connect Modbus RTU or ASCII devices. Each
port supports three serial interfaces: RS-232, RS-422, and RS-485 (both 2 and 4-wire).
15
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Pin RS-232
RS-422
RS-485 (4W)
RS-485 (2W)
1 DCD TxD- ---
2 RxD TxD+ ---
3 TxD RxD+ Data+
4 DTR RxD- Data-
5 GND GND GND
6 DSR --- ---
7 RTS --- ---
8 CTS --- ---
Power Input, Relay Output
V2+ V2-
V1+ V1-
Shielded
Ground
DC Power
Input 1
DC Power
Input 1
Relay
Output
Relay
Output
DC Power
Input 2
DC Power
Input 2