GE D30 Instruction Manual

Also see for D30 series: Communications manual Communications guide Instruction manual Instruction manual Instruction manual

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CHAPTER 5: SETTINGS CONTROL ELEMENTSD30 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL 5-2335The maximum number of autoreclosure elements available is equal to the number of installed CT banks.The autoreclosure feature is intended for use with transmission and distribution lines, in three-pole tripping schemes forsingle breaker applications. Up to four selectable reclosures "shots" are possible prior to locking out. Each shot has anindependently settable dead time. The protection settings can be changed between shots if required, using FlexLogic.Logic inputs are available for disabling or blocking the scheme.Faceplate panel LEDs indicate the state of the autoreclose scheme as follows:• Reclose Enabled — The scheme is enabled and can reclose if initiated• Reclose Disabled — The scheme is disabled• Reclose In Progress — An autoreclosure has been initiated but the breaker has not yet been signaled to close• Reclose Locked Out — The scheme has generated the maximum number of breaker closures allowed and, as the faultpersists, does not close the breaker again; known as "Lockout." The scheme can also be sent in "Lockout" when theincomplete sequence timer times out or when a block signal occurs while in "reclose in progress." The scheme must bereset from Lockout in order to perform reclose for further faults.The reclosure scheme is considered enabled when all of the following conditions are true:• The AR1 FUNCTION is set to “Enabled”• The scheme is not in the "Lockout" state• The "Block" input is not asserted• The AR1 BLK TIME UPON MNL CLS timer is not activeThe autoreclose scheme is initiated by a trip signal from any selected protection feature operand. The scheme is initiatedprovided the circuit breaker is in the closed state before protection operation.The reclose-in-progress (RIP) is set when a reclosing cycle begins following a reclose initiate signal. Once the cycle issuccessfully initiated, the RIP signal seals-in and the scheme continues through its sequence until one of the followingconditions is satisfied:• The close signal is issued when the dead timer times out, or• The scheme goes to lockoutWhile RIP is active, the scheme checks that the breaker is open and the shot number is below the limit, and then beginsmeasuring the dead time.Each of the four possible shots has an independently settable dead time. Two additional timers can be used to increase theinitial set dead times 1 to 4 by a delay equal to AR1 DELAY 1 or AR1 DELAY 2 or the sum of these two delays depending on theselected settings. This offers enhanced setting flexibility using FlexLogic operands to turn the two additional timers “on”and “off.” These operands can possibly include AR1 SHOT CNT =n, SETTING GROUP ACT 1, and so on. The autoreclose providesup to maximum 4 selectable shots. Maximum number of shots can be dynamically modified through the settings AR1REDUCE MAX TO 1 (2, 3), using the appropriate FlexLogic operand.Scheme lockout blocks all phases of the reclosing cycle, preventing automatic reclosure, if any of the following occurs:• The maximum shot number was reached• A "Block" input is in effect (for instance, Breaker Failure or bus differential protection operated)• The "Incomplete Sequence" timer times outThe recloser is latched in the Lockout state until a "reset from lockout" signal is asserted, either from a manual close of thebreaker or from a manual reset command (local or remote). The reset from lockout can be accomplished by operatorcommand, by manually closing the breaker, or whenever the breaker has been closed and stays closed for a preset time.After the dead time elapses, the scheme issues the close signal. The close signal is latched until the breaker closes or thescheme goes to Lockout.The D30 is provided with this optional feature, specified as an option at the time of ordering. Using theorder code for your device, see the order codes in chapter 2 for details.