5-372
L90 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
CONTROL ELEMENTS
CHAPTER 5: SETTINGS
5
Figure 5-213: IEC 255-8 sample operate and reset curves
The thermal overload protection element estimates accumulated thermal energy E using the following equations
calculated each power cycle. When current is greater than the pickup level, I
n
> k × I
B
, element starts increasing the
thermal energy:
Eq. 5-47
When current is less than the dropout level, I
n
> 0.97 × k × I
B
, the element starts decreasing the thermal energy:
Eq. 5-48
where
∆
t is the power cycle duration
n is the power cycle index
t
op(In)
is the trip time calculated at index n as per the IEC255-8 cold curve or hot curve equations
t
rst(In)
is the reset time calculated at index n as per the reset time equation
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 ...