ABB REL670 Installation And Commissioning Manual page 99

Table 17: Test points for phase-earth loop L3-E (Ohm/loop)
Test point Value
1
[
2
= ⋅
X X
3
R=0
2
[
2
= ⋅
X X
3
R=RIPE
3
2
= ⋅
X 0.85
= ⋅
R 0.85
4
3
= ⋅
X RFFwPE
2
3
= ⋅ ⋅
R 3
2
5
=
X RLdFw
R= RLdFw
6 X=0
R= RLdFw
7
= − ⋅
X 0.8 RLdFw
R=0.8·RLdFw
Distance protection
]
+
1 XN
]
+
1 XN
[
]
⋅ +
X 1 XN
3
2 ] 1
⋅ ⎡ + ⋅
⎣ X 1 XN
tan(60 )
3
RFFwPE
⋅
tan( ArgLd )
⋅
tan( ArgLd )
Comments
≈
X 0.981
≈
R 0.567 ( 1
+
RFFwPE )
°
≈
X 1.732 RFFwPE
X=-0.386· RLdFw
Verifying settings by secondary
[
]
⋅ +
X 1 XN
⋅ + +
X L XNL) RFFwPE
⋅
Chapter 11
injection
91