7SR21 & 7SR22 Performance Specification
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3.8.2 Operate Level ........................................................................................................ 64
3.8.3 Operate Angle ....................................................................................................... 64
3.9 Load Blinder (21LB – 1P) ................................................................................................... 65
3.9.1 Reference .............................................................................................................. 65
3.9.2 Operate Level ........................................................................................................ 65
3.9.3 Operate Angle ....................................................................................................... 65
Section 4: Control Functions.......................................................................................................... 66
4.1 Check Synchronising .......................................................................................................... 66
4.1.1 Reference .............................................................................................................. 66
4.1.2 Live/Dead Line/Bus Detector Elements .................................................................. 66
4.1.3 Line and Bus Undervoltage Elements..................................................................... 67
4.1.4 Voltage Difference ................................................................................................. 67
4.1.5 General Autoreclose Timers ................................................................................... 67
4.1.6 CS/SS/COZ Line and Bus Phase Angle Difference ................................................ 67
4.1.7 CS/SS/COZ Slip Frequency ................................................................................... 67
4.1.8 CS/SS Timer .......................................................................................................... 67
4.1.9 Split Angle Detector ............................................................................................... 68
4.1.10 Split Slip Frequency Detector ................................................................................. 68
4.2 Live/Dead........................................................................................................................... 68
4.2.1 Reference .............................................................................................................. 68
4.2.2 Live/Dead Detector Elements ................................................................................. 68