7SR210 & 7SR220 Configuration Guide
1.1.2 Standard rear RS485 connection
Figure 2.1-2 Standard rear RS485 connection to a PC
1.1.3 Optional rear fibre optic connection
Figure 2.1-3 Additional (Optional) rear fibre optic connection to a PC
Sigma devices have a 25 pin female D connector with the following pin out.
Pin Function
2 Transmit
Data
3 Received
Data
4
Request to Send
5
Clear to Send
6
Data set ready
7 Signal
Ground
8
Received Line Signal Detector
20 Data
Terminal
Ready
©2011 Siemens Protection Devices Limited
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