ABB REL670 - Page 92

84
Distance protection Chapter 11
Verifying settings by secondary
injection
Figure 27: Distance protection (ZM) characteristic with test points for phase to earth mea-
surements
Table 16 is used in conjunction with figure 27.
Table 15: Test points for phase-to-phase loops L1-L2 (Ohm/Loop)
X1+XN
R
X
(Ω / loop)
50%
80%
1
2
3
4
5
6
7
8
9
10
11
80% of RLdFw
40% of RLdFw
RFPE
12
en05000369.vsd
13
a
c
b
alt. 80% of
RFPE (Load
encroachment)
Test point Reach Set value Comments
1 X X1
set
R 0
2 X X1
set
R R1
set
3 X 0.8 x X1
set
R 0.8 x R1
set
+ RFPP/2
4 X 0.5 x X1
set
R 0.5 x R1
set
+ RFPP/2
5 X 0.85 x RFPP x tan (ArgRLd) ArgRLd = angle for the maximal load transfer
R 0.85 x RFPP
6 X RLdFw x tan (ArgLd)
R RLdFw
7 X RLdFw x tan (ArgLd)
R 0
8 X –0.2143 x RFPP/2 Exact: 0.8 x RFPP/2 (ArgDir)
R 0.8 x RFPP/2