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8-28
L60 Line Phase Comparison System
GE Multilin
8.1 OVERVIEW
8 THEORY OF OPERATION
8
Figure 8–23: DUAL-BREAKER LOGIC FOR PERMISSIVE AND BLOCKING TRANSMIT SCHEMES
For tripping (permissive) schemes, a positive polarity is declared for the terminal if one breaker displays positive polarity
when its FDL flag is set, while the other breaker either does not show the negative polarity or its FDL flag is dropped out.
The transmission logic for the blocking follows a different reasoning. Here, a blocking action must be established if any of
the two breakers sees a reverse direction. It must be kept in mind that the positive and negative pulses do not necessarily
complement each other, and therefore, one must not substitute not(positive polarity) = negative polarity.
Figure 8–24: PERMISSIVE DUAL-COMPARISON SCHEME LOGIC THROUGH FAULT CONDITION
831804A1.CDR
AND
LOC
1P_RAW
FDL
1
OR
FDL
2
FDL
2
AND
LOC
1N_RAW
OR
AND
LOC
2P_RAW
FDL
2
OR
FDL
1
FDL
1
AND
LOC
2N_RAW
LOC
P_RAW
(a)
AND
LOC
1P_RAW
FDL
1
FDL
2
OR
LOC
P_RAW
(b)
AND
LOC
2P_RAW
FDL
2
FDL
1
AND
LOC
1P_RAW
LOC
2P_RAW
AND
LOC
1P_RAW
LOC
2N_RAW
AND
LOC
2P_RAW
LOC
1N_RAW
OR
AND
FDL
1
FDL
2
831805A1.CDR
F1-IA
F2-IB
F3-IC
M1-IA
M2-IB
M3-IC
87PC BKR 1 CURRENT
87PC BKR2 CURRENT
BKR1 POS
BKR 1 FDL
BKR2 POS
BKR2 FDL
BKR 1 NEG
BKR2 NEG
POS
NEG
FDL
TX POS
TX NEG
1) CB1 currents in the forward direction
on the breaker-and-a-half diameter.
2) CB2 currents in the reverse direction;
signs of shallow CT saturation (DC
component eliminated, “tail” after the
fault is cleared).
3) Composite signals of different
magnitudes but out-of-phase.
4) CB1 produces individual pulses;
FDL picks up.
5) CB2 pulses are out-of-phase;
FDL picks up.
6) Dual breaker logic effectively erases
both positive and negative pulses.
7) FDL transmits for both breaker pickups.
8) Transmitted pulses are very short (almost
perfectly erased); no 87PC operation.
87PC OP
Summary of Contents for UR series
Page 2: ......
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Page 12: ...xii L60 Line Phase Comparison System GE Multilin TABLE OF CONTENTS ...
Page 32: ...1 20 L60 Line Phase Comparison System GE Multilin 1 5 USING THE RELAY 1 GETTING STARTED 1 ...
Page 54: ...2 22 L60 Line Phase Comparison System GE Multilin 2 2 SPECIFICATIONS 2 PRODUCT DESCRIPTION 2 ...
Page 438: ...7 8 L60 Line Phase Comparison System GE Multilin 7 2 TARGETS 7 COMMANDS AND TARGETS 7 ...
Page 478: ...8 40 L60 Line Phase Comparison System GE Multilin 8 3 FAULT LOCATOR 8 THEORY OF OPERATION 8 ...
Page 502: ...A 10 L60 Line Phase Comparison System GE Multilin A 1 PARAMETER LIST APPENDIXA A ...
Page 584: ...B 82 L60 Line Phase Comparison System GE Multilin B 4 MEMORY MAPPING APPENDIXB B ...
Page 622: ...D 10 L60 Line Phase Comparison System GE Multilin D 1 PROTOCOL APPENDIXD D ...
Page 634: ...E 12 L60 Line Phase Comparison System GE Multilin E 2 DNP POINT LISTS APPENDIXE E ...
Page 642: ...F 8 L60 Line Phase Comparison System GE Multilin F 3 WARRANTY APPENDIXF F ...