GE L60 Instructions Manual

Also see for L60: Communications manual Communications guide Instruction manual Instruction manual Instruction manual

Contents

5-280 L60 LINE PHASE COMPARISON SYSTEM – INSTRUCTION MANUALGROUPED ELEMENTS CHAPTER 5: SETTINGS5SettingsBF1 MODE — This setting is used to select the breaker failure operating mode: single or three pole.BF1 USE AMP SUPV — If set to "Yes," the element is initiated if current flowing through the breaker is above the supervisionpickup level.BF1 USE SEAL-IN — If set to "Yes," the element is sealed-in if current flowing through the breaker is above the supervisionpickup level.BF1 3-POLE INITIATE — This setting selects the FlexLogic operand that initiates three-pole tripping of the breaker.BF1 RETRIP PICKUP DELAY — This setting specifies a pickup delay for the re-trip command. Set this delay longer than thepossible spurious contact input activation duration due to transients or temporary DC grounds, taking into account thecontact input de-bounce time to avoid re-trip operation for such transients.BF1 PH AMP SUPV PICKUP — This setting is used to set the phase current initiation and seal-in supervision level. Generally thissetting detects the lowest expected fault current on the protected breaker. It can be set as low as necessary (lower thanbreaker resistor current or lower than load current)—high-set and low-set current supervision guarantee correct operation.BF1 N AMP SUPV PICKUP — This setting is used to set the neutral current initiate and seal-in supervision level. Generally thissetting detects the lowest expected fault current on the protected breaker. Neutral current supervision is used only in thethree phase scheme to provide increased sensitivity. This setting is valid only for three-pole tripping schemes.BF1 USE TIMER 1 — If set to "Yes," the early path is operational.BF1 TIMER 1 PICKUP DELAY — Timer 1 is set to the shortest time required for breaker auxiliary contact Status-1 to open, fromthe time the initial trip signal is applied to the breaker trip circuit, plus a safety margin.BF1 USE TIMER 2 — If set to "Yes," the main path is operational.BF1 TIMER 2 PICKUP DELAY — Timer 2 is set to the expected opening time of the breaker, plus a safety margin. This safetymargin was historically intended to allow for measuring and timing errors in the breaker failure scheme equipment. Inmicroprocessor relays this time is not significant. In L60 relays, which use a Fourier transform, the calculated currentmagnitude ramps-down to zero one power frequency cycle after the current is interrupted, and this lag needs to beincluded in the overall margin duration, as it occurs after current interruption. The Breaker Failure Main Path Sequencefigure that follows shows a margin of two cycles; this interval is considered the minimum appropriate for mostapplications.Note that in bulk oil circuit breakers, the interrupting time for currents less than 25% of the interrupting rating can besignificantly longer than the normal interrupting time.BF1 USE TIMER 3 — If set to "Yes," the Slow Path is operational.BF1 TIMER 3 PICKUP DELAY — Timer 3 is set to the same interval as timer 2, plus an increased safety margin. Because thispath is intended to operate only for low level faults, the delay can be in the order of 300 to 500 ms.BF1 BKR POS1 φA/3P — This setting selects the FlexLogic operand that represents the protected breaker early-type auxiliaryswitch contact (52/a). When using the single-pole breaker failure scheme, this operand represents the protected breakerearly-type auxiliary switch contact on pole A. This is normally a non-multiplied form-A contact. The contact can even beadjusted to have the shortest possible operating time.BF1 BKR POS2 φA/3P — This setting selects the FlexLogic operand that represents the breaker normal-type auxiliary switchcontact (52/a). When using the single-pole breaker failure scheme, this operand represents the protected breaker auxiliaryswitch contact on pole A. This can be a multiplied contact.BF1 BREAKER TEST ON — This setting is used to select the FlexLogic operand that represents the breaker in-service/out-of-service switch set to the out-of-service position.BF1 PH AMP HISET PICKUP — This setting sets the phase current output supervision level. Generally this setting is to detectthe lowest expected fault current on the protected breaker, before a breaker opening resistor is inserted.BF1 N AMP HISET PICKUP — This setting sets the neutral current output supervision level. Generally this setting is to detectthe lowest expected fault current on the protected breaker, before a breaker opening resistor is inserted. Neutral currentsupervision is used only in the three pole scheme to provide increased sensitivity. This setting is valid only for three-polebreaker failure schemes.