Technical Data
4.2 Protection Interfaces and Connections
SIPROTEC, 7SD80, Manual
E50417-G1140-C474-A1, Release date 09.2011
295
To select the modes of the Cu protection interface connection, please observe the following criteria:
The connection must be established in the selected mode.
The number of message errors (per minute and/or per hour) should be as small as possible (operational
measured value).
Mode
Signal noise ratio, S/N (the higher
this value the better)
Attenuation, D (the smaller this
value the better)
01 and 02
≥
12 db
≤
40 dB
03 and 04
≥
6 db
≤
40 dB
05 and 06
≥
6 db
≤
30 dB
(the signal noise ratio and the attenuation are operational measured values)
It can be possible to select several modes for a cable. Due the smaller disturbance sensitivity, modes 01 and 03 are rec-
ommended.
We recommend the following for the lines listed here as examples:
Line 1 (telephone line): Mode 03 (largest range 20 km)
Line 2 (signal line): Mode 06 (largest range 20 km for high transmission rates)
Line 3 (PVC line): Mode 03 (Range 16 km if SNR is good. The high attenuation is due to the range here)