Siemens 7SR224 - Page 224

7SR224 Argus Installation
©2010 Siemens Protection Devices Limited Chapter 5 Page 14 of 16
Figure 5.4-2 Data Comms to Multiple Devices Using Sigma 3 and F.O. Ring Network
The fibre optic data comms link will be broken if the relay element is withdrawn from the case.
Laptop computer or
Control System
Sigma
3
Tx
Rx Tx
Rx
RS 232 straight
through cable
USB or 9 pin male
D connector
25 pin male D
connector
62
.5/
125µm fibre optic with ST
connectors
Tx
Rx
Tx
Rx