CHAPTER 5: SETTINGS GROUPED ELEMENTSL60 LINE PHASE COMPARISON SYSTEM – INSTRUCTION MANUAL 5-1895The line pickup feature uses a combination of undercurrent and undervoltage to identify a line that has been de-energized(line end open). Alternately assign a FlexLogic operand to the TERMINAL OPEN setting that specifies the terminal status.Three instantaneous overcurrent elements are used to identify a previously de-energized line that has been closed onto afault. Faults other than close-in faults can be identified satisfactorily with the distance elements.Co-ordination features are included to ensure satisfactory operation when high-speed automatic reclosure (AR) isemployed. The AR CO-ORD DELAY setting allows the overcurrent setting to be below the expected load current seen afterreclose. Co-ordination is achieved by all of the LINE PICKP UV elements resetting and blocking the trip path before the ARCO-ORD DELAY times out. The AR CO-ORD BYPASS setting is normally enabled. It is disabled if high speed autoreclosure isimplemented.The line pickup protection incorporates zone 1 extension capability. When the line is being re-energized from the localterminal, pickup of an overreaching zone 2 or excessive phase current within eight power cycles after the autorecloserissues a close command results in the LINE PICKUP RCL TRIP FlexLogic operand. For security, the overcurrent trip issupervised by an undervoltage condition, which in turn is controlled by the VT FUSE FAIL OP operand with a 10 mscoordination timer. If a trip from distance is not required, then it can be disabled with the LINE PICKUP DISTANCE TRIP setting.Configure the LINE PICKUP RCL TRIP operand to perform a trip action if the intent is zone 1 extension.The zone 1 extension philosophy used here normally operates from an under-reaching zone, and it uses an overreachingdistance zone when reclosing the line with the other line end open. The AR ACCELERATE setting is provided to achieve zone1 extension functionality if external autoreclosure is employed. Another zone 1 extension approach is to applypermanently an overreaching zone, and reduce the reach when reclosing. This philosophy can be programmed via theautoreclose scheme.LINE PICKUP FUNCTION — This setting enables and disables the line pickup feature.LINE PICKUP SIGNAL SOURCE — Selects the signal source for line pickup protection.PHASE IOC LINE PICKUP — Specifies the level of line current required to declare a line pickup operation when the line is re-energized.LINE END OPEN PICKUP DELAY — Specifies the time during which the line is de-energized before the line pickup logic isarmed.LINE END OPEN RESET DELAY — Specifies the time during which the line pickup logic remains armed once the line has beenre-energized.AR CO-ORD BYPASS — The coordination timer allows the overcurrent detector to be set below the expected load currentseen after reclose. When this setting is enabled (the default value), the coordination timer is bypassed. Disable this setting(removing the bypass and inserting the timer) if high speed autoreclosure is employed. AR CO-ORD BYPASS:EnabledRange: Disabled, Enabled AR CO-ORD PICKUPDELAY: 0.045 sRange: 0.000 to 65.535 s in steps of 0.001 AR CO-ORD RESETDELAY: 0.005 sRange: 0.000 to 65.535 s in steps of 0.001 TERMINAL OPEN:OffRange: FlexLogic operand AR ACCELERATE:OffRange: FlexLogic operand LINE PICKUP DISTANCETRIP: EnabledRange: Disabled, Enabled LINE PICKUP BLOCK:OffRange: FlexLogic operand LINE PICKUPTARGET: Self-resetRange: Self-reset, Latched, Disabled LINE PICKUPEVENTS: DisabledRange: Disabled, Enabled
