Schweitzer Engineering Laboratories SEL-387E - Page 47

Date Code 20080110 Protection Functions iii
SEL-387E Instruction Manual
Time-Overcurrent Pickup....................................................................................3-50
Time-Overcurrent Curve and Time-Dial.............................................................3-50
Time-Overcurrent Element Reset Characteristic.................................................3-50
Instantaneous and Definite-Time Overcurrent Elements ............................................3-50
Instantaneous and Definite-Time Element Pickup and Time Delay Settings .............3-50
Overcurrent Element External Torque-Control...........................................................3-51
Overcurrent Settings for Example Application ...........................................................3-51
Time Overcurrent Curve Reference Information................................................................3-52
Over-/Undervoltage Element......................................................................................................3-55
Application Description ......................................................................................................3-55
Operating Characteristic .....................................................................................................3-55
Setting Descriptions ............................................................................................................3-57
Undervoltage Element Enable (E27)...........................................................................3-57
Overvoltage Element Enable (E59).............................................................................3-57
Phase Undervoltage Element Pickups (27PnP)...........................................................3-58
Phase-Phase Undervoltage Element Pickups (27PPn) ................................................3-58
Positive-Sequence Undervoltage Element Pickup (27V1P)........................................3-58
Phase Overvoltage Element Pickups (59PnP).............................................................3-58
Residual Overvoltage Element Pickups (59GnP) .......................................................3-58
Negative-Sequence Overvoltage Element Pickup (59QP)..........................................3-58
Phase-Phase Overvoltage Element Pickups (59PPn) ..................................................3-58
Positive-Sequence Overvoltage Element Pickup (59V1P)..........................................3-58
Definite-Time Characteristic.......................................................................................3-59
Frequency Element .....................................................................................................................3-59
Application Description ......................................................................................................3-59
Operating Characteristic .....................................................................................................3-59
Setting Descriptions ............................................................................................................3-61
Frequency Element Enable (E81) ...............................................................................3-61
Phase Undervoltage Block (27B81P)..........................................................................3-61
Frequency Element Pickups (81DnP) .........................................................................3-61
Frequency Element Time Delays (81DnD).................................................................3-61
Volts/Hertz Element....................................................................................................................3-61
Application Description ......................................................................................................3-61
Operating Characteristic .....................................................................................................3-61
Setting Descriptions ............................................................................................................3-64
Recommendations .......................................................................................................3-64
Phase Potential Connection (DELTA_Y) ...................................................................3-64
Volts/Hertz Protection Enable (E24)...........................................................................3-64
Protected Winding Line-to-Line Voltage (VNOM)....................................................3-64
Power Transformer Winding Connection (24WDG) ..................................................3-64
Level 1 Volts/Hertz Element Pickup (24D1P) ............................................................3-65
Level 1 Time Delay (24D1D) .....................................................................................3-65
Level 2 Composite Curve Shape (24CCS)..................................................................3-65
When 24CCS = DD:............................................................................................3-65
When 24CCS = ID: .............................................................................................3-66
When 24CCS = I: ................................................................................................3-66
When 24CCS = U:...............................................................................................3-67
When 24CCS = DD, ID, I, or U: .........................................................................3-67
Volts/Hertz Setting Reference Information ........................................................................3-68