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L90 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
GROUPED ELEMENTS
CHAPTER 5: SETTINGS
5
Igd = abs(3
×
0.0333 + 0.05) = 0.15 pu, IR0 = abs(3
×
0.033 – (0.05)) = 0.05 pu, IR2 = 3
×
0.033 = 0.10 pu,
IR1 = 1.033 / 8 = 0.1292 pu, and Igr = 0.1292 pu
Despite very low fault current level, the differential current is above 100% of the restraining current.
Example 5: Internal low-current, high-load single-line-to-ground fault with no feed from the ground
Given the following inputs: IA = 1.10 pu
∠
0°, IB = 1.0 pu
∠
–120°, IC = 1.0 pu
∠
120°, and IG = 0.0 pu
∠
0°
The relay calculates the following values:
I_0 = 0.033 pu
∠
0°, I_2 = 0.033 pu
∠
0°, and I_1 = 1.033 pu
∠
0°
Igd = abs(3
×
0.0333 + 0.0) = 0.10 pu, IR0 = abs(3
×
0.033 – (0.0)) = 0.10 pu, IR2 = 3
×
0.033 = 0.10 pu,
IR1 = 1.033 / 8 = 0.1292 pu, and Igr = 0.1292 pu
Despite very low fault current level the differential current is above 75% of the restraining current.
Example 6: Internal high-current single-line-to-ground fault with no feed from the ground
Given the following inputs: IA = 10 pu
∠
0°, IB = 0 pu, IC = 0 pu, and IG = 0 pu
The relay calculates the following values:
I_0 = 3.3 pu
∠
0°, I_2 = 3.3 pu
∠
0°, and I_1 = 3.3 pu
∠
0°
Igd = abs(3
×
3.3 + 0.0) = 10 pu, IR0 = abs(3
×
3.3 – (0.0)) = 10 pu, IR2 = 3
×
3.3 = 10 pu, IR1 = 3
×
(3.33 – 3.33) = 0 pu, and
Igr = 10 pu
The differential current is 100% of the restraining current.
5.7.12 Negative sequence current
5.7.12.1 Menu
SETTINGS
GROUPED ELEMENTS
SETTING GROUP 1(6)
NEGATIVE SEQUENCE CURRENT
The L90 provides two negative-sequence time overcurrent elements, two negative-sequence instantaneous overcurrent
elements, and two negative-sequence directional overcurrent elements. For information on the negative sequence time
overcurrent curves, see the Inverse TOC Curve Characteristics section earlier.
5.7.12.2 Negative sequence time overcurrent (ANSI 51Q, IEC PTOC)
SETTINGS
GROUPED ELEMENTS
SETTING GROUP 1(6)
NEGATIVE SEQUENCE CURRENT
NEG SEQ TOC1(2)
NEGATIVE SEQUENCE
CURRENT
NEG SEQ TOC1
See below
NEG SEQ TOC2
NEG SEQ IOC1
NEG SEQ IOC2
NEG SEQ DIR OC1
NEG SEQ DIR OC2
NEG SEQ TOC1
NEG SEQ TOC1
FUNCTION: Disabled
Range: Disabled, Enabled
NEG SEQ TOC1 SIGNAL
SOURCE: SRC 1
Range: SRC 1, SRC 2, SRC 3, SRC 4
Содержание L90
Страница 14: ...1 4 L90 LINE CURRENT DIFFERENTIAL SYSTEM INSTRUCTION MANUAL FOR FURTHER ASSISTANCE CHAPTER 1 INTRODUCTION 1 ...
Страница 68: ...2 54 L90 LINE CURRENT DIFFERENTIAL SYSTEM INSTRUCTION MANUAL SPECIFICATIONS CHAPTER 2 PRODUCT DESCRIPTION 2 ...
Страница 136: ...3 68 L90 LINE CURRENT DIFFERENTIAL SYSTEM INSTRUCTION MANUAL CONNECT TO D400 GATEWAY CHAPTER 3 INSTALLATION 3 ...
Страница 224: ...4 88 L90 LINE CURRENT DIFFERENTIAL SYSTEM INSTRUCTION MANUAL FLEXLOGIC DESIGN USING ENGINEER CHAPTER 4 INTERFACES 4 ...
Страница 692: ...6 36 L90 LINE CURRENT DIFFERENTIAL SYSTEM INSTRUCTION MANUAL PRODUCT INFORMATION CHAPTER 6 ACTUAL VALUES 6 ...
Страница 708: ...7 16 L90 LINE CURRENT DIFFERENTIAL SYSTEM INSTRUCTION MANUAL TARGETS MENU CHAPTER 7 COMMANDS AND TARGETS 7 ...
Страница 742: ...9 6 L90 LINE CURRENT DIFFERENTIAL SYSTEM INSTRUCTION MANUAL TESTING CHAPTER 9 COMMISSIONING 9 ...
Страница 804: ...10 62 L90 LINE CURRENT DIFFERENTIAL SYSTEM INSTRUCTION MANUAL FAULT LOCATOR CHAPTER 10 THEORY OF OPERATION 10 ...
Страница 872: ...C 6 L90 LINE CURRENT DIFFERENTIAL SYSTEM INSTRUCTION MANUAL COMMAND LINE INTERFACE APPENDIX C COMMAND LINE INTERFACE C ...
Страница 878: ...D 6 L90 LINE CURRENT DIFFERENTIAL SYSTEM INSTRUCTION MANUAL REVISION HISTORY APPENDIX D MISCELLANEOUS D ...
Страница 882: ...iv L90 LINE CURRENT DIFFERENTIAL SYSTEM INSTRUCTION MANUAL ABBREVIATIONS ...
Страница 900: ...xviii L90 LINE CURRENT DIFFERENTIAL SYSTEM INSTRUCTION MANUAL INDEX ...