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GE Multilin
L30 Line Current Differential System
10-5
10 APPLICATION OF SETTINGS
10.2 CURRENT DIFFERENTIAL (87L) SETTINGS
10
•
For relay 3, channel 1 communicates to relay 1 and channel 2 communicates to relay 2
Consequently, to achieve the maximum sensitivity of 0.2 pu at the terminal with a CT ratio of 2000/5 (400 amps line primary
differential current), the following pickup values are chosen:
(EQ 10.17)
Choosing relay as a reference with a breakpoint value of 5.0 pu, breakpoints for relays 2 and 3 are calculated as follows:
(EQ 10.18)
(EQ 10.19)
To verify the calculated values, we have:
(EQ 10.20)
This satisfies the equality condition indicated earlier.
During on-load tests, the differential current at all terminals should be the same and generally equal to the charging current
if the tap and CT ratio settings are chosen correctly.
Pickup relay 1
0.4
Pickup relay 2
0.2
Pickup relay 3
0.8
Breakpoint relay 2
Breakpoint relay 1
CT
ratio
relay 1
CT
ratio
relay 2
----------------------------------------
5.0
1000 5
2000 5
--------------------
2.5
Breakpoint relay 3
Breakpoint relay 1
CT
ratio
relay 1
CT
ratio
relay 3
----------------------------------------
5.0
1000 5
500 5
--------------------
10.0
Breakpoint relay 1
CT
ratio
relay 1
5.0 1000 5
1000
Breakpoint relay 2
CT
ratio
relay 2
2.5 2000 5
1000
Breakpoint relay 3
CT
ratio
relay 3
10.0 5000 5
1000
Содержание L30
Страница 10: ...x L30 Line Current Differential System GE Multilin TABLE OF CONTENTS ...
Страница 30: ...1 20 L30 Line Current Differential System GE Multilin 1 5 USING THE RELAY 1 GETTING STARTED 1 ...
Страница 58: ...2 28 L30 Line Current Differential System GE Multilin 2 4 SPECIFICATIONS 2 PRODUCT DESCRIPTION 2 ...
Страница 126: ...4 30 L30 Line Current Differential System GE Multilin 4 3 FACEPLATE INTERFACE 4 HUMAN INTERFACES 4 ...
Страница 370: ...5 244 L30 Line Current Differential System GE Multilin 5 10 TESTING 5 SETTINGS 5 ...
Страница 396: ...6 26 L30 Line Current Differential System GE Multilin 6 5 PRODUCT INFORMATION 6 ACTUAL VALUES 6 ...
Страница 450: ...10 10 L30 Line Current Differential System GE Multilin 10 4 INSTANTANEOUS ELEMENTS 10 APPLICATION OF SETTINGS 10 ...
Страница 464: ...A 10 L30 Line Current Differential System GE Multilin A 1 PARAMETER LISTS APPENDIX A A ...
Страница 600: ...C 30 L30 Line Current Differential System GE Multilin C 7 LOGICAL NODES APPENDIX C C ...
Страница 610: ...D 10 L30 Line Current Differential System GE Multilin D 1 IEC 60870 5 104 APPENDIX D D ...
Страница 622: ...E 12 L30 Line Current Differential System GE Multilin E 2 DNP POINT LISTS APPENDIX E E ...
Страница 634: ...F 12 L30 Line Current Differential System GE Multilin F 3 WARRANTY APPENDIX F F ...
Страница 644: ...x L30 Line Current Differential System GE Multilin INDEX ...