GE D60 Instruction Manual

Also see for D60: Communications manual Communications guide Instruction manual Instruction manual Instruction manual

Contents

5-294 D60 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUALCONTROL ELEMENTS CHAPTER 5: SETTINGS5The trip output element works in association with other D60 elements that must be programmed and in-service forsuccessful operation. The necessary elements are: recloser, breaker control, open pole detector, and phase selector. Therecloser must also be in the “Reset” state before a single pole trip can be issued. Outputs from this element are also directlyconnected as initiate signals to the breaker failure elements.At least one internal protection element or digital input representing detection of a fault must be available as an input tothis element. In pilot-aided scheme applications, a timer can be used to delay the output decision until data from a remoteterminal is received from communications facilities, to prevent a three pole operation where a single pole operation ispermitted.The following settings are available for the trip output element.TRIP MODE — This setting is used to select the required mode of operation. If selected to “3 Pole Only” outputs for all threephases are always set simultaneously. If selected to “3 Pole & 1 Pole” outputs for all three phases are set simultaneouslyunless the phase selector or a pilot aided scheme determines the fault is single-phase-to-ground. If the fault is identified asbeing AG, BG, or CG only, the operands for the faulted phase are asserted.TRIP 3-POLE INPUT1 to TRIP 3-POLE INPUT6 — These settings are used to select an operand representing a fault conditionthat is not wanted to initiate a single pole operation (for example, phase undervoltage). Use a FlexLogic OR-gate if morethan six inputs are required.TRIP 1-POLE INPUT1 to TRIP 1-POLE INPUT6 — These settings are used to select an operand representing a fault conditionthat is wanted to initiate a single pole trip-and-reclose if the fault is single phase to ground (for example, distance zone 1).Use a FlexLogic OR-gate if more than six inputs are required. The inputs do not have to be phase-specific as the phaseselector determines the fault type.The AR FORCE 3-P TRIP operand is asserted by the autorecloser 1.5 cycles after single-pole reclosing is initiated. This operandcalls for a three-pole trip if any protection element configured under TRIP 1-POLE INPUT remains picked-up. The open poledetector provides blocking inputs to distance elements, and therefore the latter resets immediately after the TRIP 1-POLEoperand asserts. For other protection elements used in single-pole tripping, ensure that they reset immediately aftertripping, otherwise the fact that they are still picked up is detected as an evolving fault and the relay trips three-poles. Forexample, if high-set phase instantaneous overcurrent is used (TRIP 1-POLE INPUT X: “PHASE IOC1 OP”), then OPEN POLE OP ΦAis used for blocking phase A of the instantaneous overcurrent element. In this way, after tripping phase A, the phase ainstantaneous overcurrent element is forced to reset. Phases B and C are still operational and can detect an evolving faultas soon as 8 ms after tripping phase A. Neutral and negative-sequence instantaneous overcurrent elements are blockedfrom the OPEN POLE BLK N operand unless the pickup setting is high enough to prevent pickup during single-pole reclosing.TRIP RECLOSE INPUT1 to TRIP RECLOSE INPUT6 — These settings select an operand representing a fault condition that iswanted to initiate three pole reclosing (for example, phase distance zone 1). Use a FlexLogic OR-gate if more than sixinputs are required. These inputs also include the TRIP 1-POLE INPUT1 to TRIP 1-POLE INPUT6 values, which are intended toinitiate three-pole reclosing in situations where single-pole tripping commands are changed to three-pole trippingcommands. This can happen in cases where the phase selector identifies a multi-phase fault or the AR FORCE 3P TRIPcommand is present.TRIP SEAL-IN DELAY — This setting specifies the minimum time that trip command signals are maintained to providesufficient time to open the breaker poles. If a value of “0” is specified, then the output signal is reset once the protectionelements initiating the trip are reset. If a value other than “0” is specified, then the protection elements must reset and thetimer initiated at the first trip command must expire.TRIP RESET — This setting selects the option to reset the trip latches. If “Pole Curr OR Custom” is chosen, then program theOPEN POLE CURRENT PKP setting accordingly. If “CBaux OR Custom” is chosen, then set the breakers appropriately. Both the“Current” and “CBaux” options can be complimented by custom conditions using the BKR ΦA OPEN, BKR ΦB OPEN, and BKRΦC OPEN settings indicated below. Alternately, a purely custom condition can be applied to reset trip output latches.To ensure correct operation of the single pole tripping feature, any non-distance protection used for single poletripping (such as high-set overcurrent using the instantaneous or directional overcurrent elements) must beblocked by the OPEN POLE OP ΦA, OPEN POLE OP ΦB, or OPEN POLE OP ΦC operands. For example, instantaneousovercurrent phase A is blocked by OPEN POLE OP ΦA operand. This blocking condition is pre-wired for distanceprotection.