Retrieving Reclosing Status from the Relay ..................................................................................... 4-34
Virtual Switches.................................................................................................................................... 4-36
43 - Virtual Selector Switches .......................................................................................................... 4-36
BESTlogic Settings for Virtual Selector Switches ......................................................................... 4-36
Select Before Operate Control of Virtual Selector Switches ........................................................ 4-37
Retrieving Virtual Selector Switches Status from the Relay ......................................................... 4-38
101 - Virtual Breaker Control Switch ................................................................................................ 4-38
BESTlogic Settings for Virtual Breaker Control Switch ................................................................ 4-39
Select Before Operate Control of Virtual Breaker Control Switch ................................................ 4-40
Retrieving Breaker Control Switch Status from the Relay ............................................................ 4-40
Figures
Figure 4-1. Setting Group Control Logic Block .......................................................................................... 4-2
Figure 4-2. BESTlogic Function Element Screen, Setting Group Selection .............................................. 4-3
Figure 4-3. Input Control Discrete Inputs................................................................................................... 4-4
Figure 4-4. Input Control Binary Inputs ...................................................................................................... 4-5
Figure 4-5. Setting Group Selection Screen .............................................................................................. 4-5
Figure 4-6. Automatic Operation Based on Load Change ........................................................................ 4-7
Figure 4-7. Setting Group Selection Screen .............................................................................................. 4-8
Figure 4-8. Automatic Operation Based on Cold Load Pickup .................................................................. 4-8
Figure 4-9. Instantaneous Overcurrent Logic Block ................................................................................ 4-10
Figure 4-10. BESTlogic Function Element Screen, Phase (50TP) ......................................................... 4-11
Figure 4-11. Overcurrent Screen, 50T Tab ............................................................................................. 4-12
Figure 4-12. Time Overcurrent Logic Block ............................................................................................. 4-13
Figure 4-13. BESTlogic Function Element Screen, Phase (51P) ............................................................ 4-14
Figure 4-14. Overcurrent Screen, 51 Tab................................................................................................ 4-15
Figure 4-15. Curve Coefficients Screen .................................................................................................. 4-17
Figure 4-16. Phase-to-Phase Fault Magnitude ....................................................................................... 4-18
Figure 4-17. Sequence Components for an A-B Fault ............................................................................ 4-19
Figure 4-18. Breaker Failure Logic Block ................................................................................................ 4-20
Figure 4-19. BESTlogic Function Element Screen, Breaker Failure ....................................................... 4-21
Figure 4-20. Breaker Failure Screen ....................................................................................................... 4-22
Figure 4-21. General Purpose Logic Timers Logic Block ........................................................................ 4-23
Figure 4-22. Mode 1, PU/DO (Pickup/Dropout Timer) ............................................................................ 4-24
Figure 4-23. Mode 2, One-Shot Nonretriggerable Timer ......................................................................... 4-24
Figure 4-24. Mode 3, One-Shot Retriggerable Timer .............................................................................. 4-24
Figure 4-25. Mode 4, Oscillator ............................................................................................................... 4-25
Figure 4-26. Mode 5, Integrating Timer ................................................................................................... 4-25
Figure 4-27. Mode 6, Latch ..................................................................................................................... 4-26
Figure 4-28. BESTlogic Function Element Screen, 62 ............................................................................ 4-26
Figure 4-29. Logic Timers Screen ........................................................................................................... 4-27
Figure 4-30. Reclosing Logic Block ......................................................................................................... 4-28
Figure 4-31. Recognition Dropout Timing................................................................................................ 4-29
Figure 4-32. 79SCB Logic ....................................................................................................................... 4-30
Figure 4-33. BESTlogic Function Element Screen, 79 ............................................................................ 4-30
Figure 4-34. Reclosing Screen ................................................................................................................ 4-31
Figure 4-35. S#-79SCB=1/2/3/4/5 Logic Timing Diagram ....................................................................... 4-33
Figure 4-36. S#-79SCB=2/3/4/5 Logic Timing Diagram .......................................................................... 4-33
Figure 4-37. BESTlogic Function Element Screen, Reclosing (Zone Sequence Logic) ......................... 4-34
Figure 4-38. Overall Logic Diagram for Reclosing .................................................................................. 4-35
Figure 4-39. Virtual Selector Switches Logic Block ................................................................................. 4-36
Figure 4-40. BESTlogic Function Element Screen, 43 ............................................................................ 4-37
Figure 4-41. 101 Function Block .............................................................................................................. 4-38
Figure 4-42. 101 Control Switch State Diagram ...................................................................................... 4-39
Figure 4-43. BESTlogic Function Element Screen, 101 .......................................................................... 4-39
Tables
Table 4-1. BESTlogic Settings for Setting Group Control ......................................................................... 4-3
Table 4-2. Setting Group Binary Codes..................................................................................................... 4-4
Table 4-3. Operating Settings for Setting Group Control. ......................................................................... 4-6
ii
BE1-851 Protection and Control
9289900990 Rev R