CHAPTER 5: SETTINGS GROUPED ELEMENTSL90 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL 5-2735In general, a breaker failure scheme determines that a breaker signaled to trip has not cleared a fault within a definitetime, so further tripping action must be performed. Tripping from the breaker failure scheme should trip all breakers, bothlocal and remote, that can supply current to the faulted zone. Usually operation of a breaker failure element causesclearing of a larger section of the power system than the initial trip. Because breaker failure can result in tripping a largenumber of breakers and this affects system safety and stability, a very high level of security is required. BF1 USE TIMER 2:YesRange: Yes, No BF1 TIMER 2 PICKUPDELAY: 0.000 sRange: 0.000 to 65.535 s in steps of 0.001 BF1 USE TIMER 3:YesRange: Yes, No BF1 TIMER 3 PICKUPDELAY: 0.000 sRange: 0.000 to 65.535 s in steps of 0.001 BF1 BKR POS1 φA/3P:OffRange: FlexLogic operand BF1 BKR POS2 φA/3P:OffRange: FlexLogic operand BF1 BREAKER TEST ON:OffRange: FlexLogic operand BF1 PH AMP HISETPICKUP: 1.050 puRange: 0.020 to 30.000 pu in steps of 0.001 BF1 N AMP HISETPICKUP: 1.050 puRange: 0.020 to 30.000 pu in steps of 0.001 BF1 PH AMP LOSETPICKUP: 1.050 puRange: 0.020 to 30.000 pu in steps of 0.001 BF1 N AMP LOSETPICKUP: 1.050 puRange: 0.020 to 30.000 pu in steps of 0.001 BF1 LOSET TIMEDELAY: 0.000 sRange: 0.000 to 65.535 s in steps of 0.001 BF1 TRIP DROPOUTDELAY: 0.000 sRange: 0.000 to 65.535 s in steps of 0.001 BF1 TARGET:Self-ResetRange: Self-reset, Latched, Disabled BF1 EVENTS:DisabledRange: Disabled, Enabled BF1 PH A INITIATE:OffRange: FlexLogic operandValid only for 1-Pole breaker failure schemes BF1 PH B INITIATE:OffRange: FlexLogic operandValid only for 1-Pole breaker failure schemes BF1 PH C INITIATE:OffRange: FlexLogic operandValid only for 1-Pole breaker failure schemes BF1 BKR POS1 φB:OffRange: FlexLogic operandValid only for 1-Pole breaker failure schemes BF1 BKR POS1 φC:OffRange: FlexLogic operandValid only for 1-Pole breaker failure schemes BF1 BKR POS2 φB:OffRange: FlexLogic operandValid only for 1-Pole breaker failure schemes BF1 BKR POS2 φC:OffRange: FlexLogic operandValid only for 1-Pole breaker failure schemes
