User 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).
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