
APPENDIX A • TIME OVERCURRENT
CHARACTERISTIC CURVES
TABLE OF CONTENTS
APPENDIX A • TIME OVERCURRENT CHARACTERISTIC CURVES ................................................... A-1
General .................................................................................................................................................. A-1
Curve Specifications .............................................................................................................................. A-1
Time Overcurrent Characteristic Curves ............................................................................................... A-2
Time Dial Setting Cross-Reference .................................................................................................... A-3
Figures
Figure A-1. Time Characteristic Curve S1, Short Inverse (Similar to ABB CO-2) ..................................... A-5
Figure A-2. Time Characteristic Curve S2, Short Inverse (Similar To GE IAC-55) ................................... A-6
Figure A-3. Time Characteristic Curve L1, Long Inverse (Similar to ABB CO-5) ...................................... A-7
Figure A-4. Time Characteristic Curve L2, Long Inverse (Similar To GE IAC-66) .................................... A-8
Figure A-5. Time Characteristic Curve D, Definite Time (Similar To ABB CO-6) ..................................... A-9
Figure A-6. Time Characteristic Curve M, Moderately Inverse (Similar to ABB CO-7) ........................... A-10
Figure A-7. Time Characteristic Curve I1, Inverse Time (Similar to ABB CO-8) ..................................... A-11
Figure A-8. Time Characteristic Curve I2, Inverse Time (Similar to GE IAC-51) .................................... A-12
Figure A-9. Time Characteristic Curve V1, Very Inverse (Similar to ABB CO-9) .................................... A-13
Figure A-10. Time Characteristic Curve V2, Very Inverse (Similar to GE IAC-53) ................................. A-14
Figure A-11. Time Characteristic Curve E1, Extremely Inverse (Similar to ABB CO-11) ....................... A-15
Figure A-12. Time Characteristic Curve E2, Extremely Inverse (Similar to GE IAC-77) ......................... A-16
Figure A-13. Time Characteristic Curve A, Standard Inverse ................................................................. A-17
Figure A-14. Time Characteristic Curve B, Very Inverse ........................................................................ A-18
Figure A-15. Time Characteristic Curve C, Extremely Inverse ............................................................... A-19
Figure A-16. Time Characteristic Curve G, Long Time Inverse .............................................................. A-20
Tables
Table A-1. 51P, 51N, and 51Q Time Characteristic Curve Constants ...................................................... A-2
Table A-2. Characteristic Curve Cross-Reference .................................................................................... A-3
Table A-3. Time Dial Setting Cross-Reference ......................................................................................... A-4
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BE1-851 Time Overcurrent Characteristic Curves
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