ABB REG650 - Page 142

IdUnre
IDL1MAG
2nd and
5th
Harmonic
I D L
1
AND
Cross Block
from L2 or L3
OpCrossBlock=On
IBIAS
TRIPUNREL1
STL1
TRIPRESL1
B
L K H
L 1
en07000020.vsd
a
b
b>a
AND
C
r o s
s B l o
c k
t o L 2
o r L
3
AND
AND
AND
BLKUNRES
BLOCK
BLKRES
OR
1
INTFAULT
IEC07000020 V2 EN
Figure 57: Generator differential logic diagram 1.
Internal/
External
Fault
discrimin
ator
STL1
STL2
STL3
OR
AND
E
X
T
F
A U
L
T
INTFAULT
TRNSSENS
T R N S U N R
en07000021.vsd
Constant
IBIAS
a
b
b>a
Neg.Seq. Diff
Current
Contributions
OpNegSeqDiff=On
AND
BLKNSSEN
BLKNSUNR
BLOCK
IEC07000021 V2 EN
Figure 58: Generator differential logic diagram 2.
Section 6 1MRK 502 048-UEN A
Differential protection
136
Technical manual