ABB Relion 670 Series Applications Manual page 448

Section 16
Monitoring
ANSI05000045 V2 EN-US
Figure 206: Simplified network configuration with network data, required for settings of the
For a single-circuit line (no parallel line), the figures for mutual zero-sequence impedance (X
R ) and analog input are set at zero.
0M
Power system specific parameter settings are not general settings but specific setting included in
the setting groups, that is, this makes it possible to change conditions for the Fault locator with
short notice by changing setting group.
The source impedance is not constant in the network. However, this has a minor influence on the
accuracy of the distance-to-fault calculation, because only the phase angle of the distribution
factor has an influence on the accuracy. The phase angle of the distribution factor is normally very
low and practically constant, because the positive sequence line impedance, which has an angle
close to 90°, dominates it. Always set the source impedance resistance to values other than zero. If
the actual values are not known, the values that correspond to the source impedance
characteristic angle of 85° give satisfactory results.
16.8.3.1 Connection of analog currents
Connection diagram for analog currents included IN from parallel line shown in figure
442
R +jX
0L
R +jX
1L
R +jX
1A 1A
Z =Z
0m 0m
R +jX
0L
R +jX
1L
DRPRDRE
LMBRFLO
fault location-measuring function
0L
1L
R +jX
1B 1B
+jX
0m
0L
1L
ANSI05000045_2_en.vsd
1MRK 511 358-UUS A
,
0M
M13769-16 v4
207
Application manual