SECTION 4 • PROTECTION AND CONTROL
TABLE OF CONTENTS
SECTION 4 • PROTECTION AND CONTROL ......................................................................................... 4-1
Introduction ............................................................................................................................................ 4-1
Using Protection and Control Functions ............................................................................................. 4-1
Setting Groups ....................................................................................................................................... 4-1
BESTlogic Settings for Setting Group Control ................................................................................... 4-2
Operating Settings for Setting Group Control .................................................................................... 4-5
Logic Override of the Setting Group Control Function ....................................................................... 4-9
Retrieving Setting Group Control Status from the Relay ................................................................... 4-9
Overcurrent Protection ......................................................................................................................... 4-10
50T - Instantaneous Overcurrent Protection with Settable Time Delay ........................................... 4-10
BESTlogic Settings for Instantaneous Overcurrent Protection .................................................... 4-10
Operating Settings for Instantaneous Overcurrent Protection...................................................... 4-11
Retrieving Instantaneous Overcurrent Protection Status from the Relay ..................................... 4-13
51 - Time Overcurrent Protection ..................................................................................................... 4-13
BESTlogic Settings for Time Overcurrent Protection ................................................................... 4-14
Operating Settings for Time Overcurrent Protection .................................................................... 4-15
Setting Programmable Time Current Characteristic Curve Coefficients ...................................... 4-16
Retrieving Time Overcurrent Protection Status from the Relay ................................................... 4-18
Negative-Sequence Overcurrent Protection .................................................................................... 4-18
Pickup Settings for Negative-Sequence Overcurrent ................................................................... 4-18
Coordination Settings for Negative-Sequence Overcurrent Protection ........................................ 4-19
Delta/Wye Transformer Application .............................................................................................. 4-19
Breaker Failure Protection ................................................................................................................... 4-20
BF - Breaker Failure Protection ........................................................................................................ 4-20
BESTlogic Settings for Breaker Failure Protection ....................................................................... 4-21
Operating Settings for Breaker Failure Protection ........................................................................ 4-22
Retrieving Breaker Failure Protection Status from the Relay ....................................................... 4-23
Logic Timers......................................................................................................................................... 4-23
62 - General Purpose Logic Timers ................................................................................................. 4-23
Mode 1, PU/DO (Pickup/Dropout Timer) ...................................................................................... 4-24
Mode 2, One-Shot Nonretriggerable Timer .................................................................................. 4-24
Mode 3, One-Shot Retriggerable Timer ....................................................................................... 4-24
Mode 4, Oscillator ......................................................................................................................... 4-25
Mode 5, Integrating Timer ............................................................................................................ 4-25
Mode 6, Latch ............................................................................................................................... 4-26
BESTlogic Settings for General Purpose Logic Timers ................................................................ 4-26
Operating Settings for General Purpose Logic Timers ................................................................. 4-27
Retrieving General Purpose Logic Timers Status from the Relay ................................................ 4-28
Reclosing ............................................................................................................................................. 4-28
Inputs and Outputs ........................................................................................................................... 4-29
Reclose Initiate (RI) ...................................................................................................................... 4-29
Breaker Status (STATUS) ............................................................................................................ 4-29
Reclose Wait (WAIT) .................................................................................................................... 4-29
Drive to Lockout/Block Recloser (DTL/BLK) ................................................................................ 4-29
Close (79C) ................................................................................................................................... 4-29
Recloser Running (79RNG) .......................................................................................................... 4-29
Lockout (79LO) ............................................................................................................................. 4-29
Recloser Fail Timer (79F) ............................................................................................................. 4-30
Sequence Controlled Block (79SCB) ........................................................................................... 4-30
BESTlogic Settings for Reclosing .................................................................................................... 4-30
Operating Settings for Reclosing ..................................................................................................... 4-31
Reset Timer (79RST).................................................................................................................... 4-32
Maximum Cycle Timer (MAX Cycle) ............................................................................................. 4-32
Sequence Controlled Block (SCB) ............................................................................................... 4-32
Zone-Sequence Coordination .......................................................................................................... 4-33
9289900990 Rev R
BE1-851 Protection and Control
i
