Optional Rear Rs485 (Com3) - Siemens Argus 7SR21 Technical Manual

Computer or
Control System
USB or 9 pin male
D connector
Fig. 2-3 Communication to Multiple Devices using Fibre-optic Ring Network
RS232 straight
through cable
Computer or
Control System
USB or 9 pin male
D connector
Fig. 2-4 Communication to Multiple Devices from Control System and Laptop using Fibre-optic Star Network

2.5 Optional Rear RS485 (COM3)

The following settings, on the COMMUNICATIONS MENU, must be configured when using the electrical 2-wire RS485
Com3 interface.
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RS232 to Fibre
Optic Converter
RS232 straight
through cable
Tx
Rx
25 pin male
D connector
To
Control
System
7SG24 Sigma 1
Tx
Master
Rx
Tx
Rx
Tx
Rx
Tx
Rx
Tx
Rx
25 pin male
D connector
Chapter 4 - Data Communications Definitions
Rx
Tx
62.5/125µm fibre optic with ST
connectors
Rx
Tx
62.5/125µm fibre optic
with ST connectors
Rx
Tx
Rx
Tx
Rx
Tx
Rx
Tx
Chapter 4 - Page 13 of 96