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CHAPTER 9: THEORY OF OPERATION
OUTPUT LOGIC AND EXAMPLES
B30 BUS DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
9-11
9
Figure 9-9: Output logic of biased differential protection
9.6.2 Internal and external fault example
Two examples of relay operation are presented: an external fault with heavy CT saturation and an internal fault.
The protected bus includes six circuits connected to CT terminals F1, F5, M1, M5, U1, and U5, respectively. The circuits F1,
F5, M1, M5, and U5 are capable of feeding some fault current; the U1 circuit supplies a load. The F1, F5, and U5 circuits are
significantly stronger than the F5 and M1 connections.
The M5 circuit contains the weakest (most prone to saturation) CT of the bus.
The first of the following figures presents the bus currents and the most important logic signals for the case of an external
fault. Despite very fast and severe CT saturation, the B30 remains stable.
The second figure presents the same signals but for the case of an internal fault. The B30 trips in 10 ms (fast form-C output
contact).
Содержание b30
Страница 10: ...x B30 BUS DIFFERENTIAL SYSTEM INSTRUCTION MANUAL TABLE OF CONTENTS ...
Страница 14: ...1 4 B30 BUS DIFFERENTIAL SYSTEM INSTRUCTION MANUAL FOR FURTHER ASSISTANCE CHAPTER 1 INTRODUCTION 1 ...
Страница 50: ...2 36 B30 BUS DIFFERENTIAL SYSTEM INSTRUCTION MANUAL SPECIFICATIONS CHAPTER 2 PRODUCT DESCRIPTION 2 ...
Страница 208: ...4 86 B30 BUS DIFFERENTIAL SYSTEM INSTRUCTION MANUAL FLEXLOGIC DESIGN USING ENGINEER CHAPTER 4 INTERFACES 4 ...
Страница 441: ...CHAPTER 5 SETTINGS CONTROL ELEMENTS B30 BUS DIFFERENTIAL SYSTEM INSTRUCTION MANUAL 5 233 5 Figure 5 123 Time out mode ...
Страница 486: ...5 278 B30 BUS DIFFERENTIAL SYSTEM INSTRUCTION MANUAL TESTING CHAPTER 5 SETTINGS 5 ...
Страница 514: ...6 28 B30 BUS DIFFERENTIAL SYSTEM INSTRUCTION MANUAL PRODUCT INFORMATION CHAPTER 6 ACTUAL VALUES 6 ...
Страница 528: ...7 14 B30 BUS DIFFERENTIAL SYSTEM INSTRUCTION MANUAL TARGETS MENU CHAPTER 7 COMMANDS AND TARGETS 7 ...
Страница 554: ...9 14 B30 BUS DIFFERENTIAL SYSTEM INSTRUCTION MANUAL OUTPUT LOGIC AND EXAMPLES CHAPTER 9 THEORY OF OPERATION 9 ...
Страница 600: ...A 16 B30 BUS DIFFERENTIAL SYSTEM INSTRUCTION MANUAL FLEXANALOG ITEMS APPENDIX A FLEXANALOG OPERANDS A ...
Страница 608: ...C 6 B30 BUS DIFFERENTIAL SYSTEM INSTRUCTION MANUAL COMMAND LINE INTERFACE APPENDIX C COMMAND LINE INTERFACE C ...
Страница 616: ...iv B30 BUS DIFFERENTIAL SYSTEM INSTRUCTION MANUAL ABBREVIATIONS ...
Страница 632: ...xvi B30 BUS DIFFERENTIAL SYSTEM INSTRUCTION MANUAL INDEX ...