Fieldbus Appendix - ANYBUS®-S Modbus RTU
DOC. ABS-APPENDIX-RTU Rev 1.00
2003-04-28
3 Hardware design
3.1 Fieldbus Connectors
The Modbus RTU standard recommends the use of a 9 pin female D-sub connector. Depending on the protection class and type of application, other connector designs are also allowed.
3.1.1 D-SUB
Pin |
Name |
Functiion |
|
|
|
Housing |
PE |
Protective Earth |
|
|
|
1 |
- |
Not connected |
|
|
|
2 |
RS232 - TX |
Transmit signal |
|
|
|
3 |
RS232 - RX |
Receive signal |
|
|
|
4 |
- |
Not connected |
|
|
|
5 |
GND (GALV) |
Ground |
|
|
|
6 |
+5 V (GALV) |
Power supply |
|
|
|
7 |
RS 485 B - LINE |
|
|
|
|
8 |
RS 485 A - LINE |
|
|
|
|
9 |
- |
Not connected |
|
|
|
Table 1: D-SUB
3.1.2 Screw terminal
Pin |
Name |
Functiion |
|
|
|
1 |
RS232 - TX |
Transmit signal |
|
|
|
2 |
GND (GALV) |
Ground |
|
|
|
3 |
RS485 A - LINE |
|
|
|
|
4 |
RS485 B - LINE |
|
|
|
|
5 |
RS232 - RX |
Receive signal |
|
|
|
6 |
PE |
Protective Earth |
|
|
|
Table 2: Screw terminal
HMS INDUSTRIAL NETWORKS AB |
9 |