GE L60 Instruction Manual

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

Contents

GE Multilin L60 Line Phase Comparison Relay 5-1655 SETTINGS 5.6 CONTROL ELEMENTS5This element is primarily used to collect trip requests from protection elements and other inputs to generate output oper-ands to initiate trip operations. Three pole trips will only initiate reclosure if programmed to do so, whereas single pole tripswill always automatically initiate reclosure. The TRIP 3-POLE and TRIP 1-POLE output operands can also be used as inputsto a FlexLogic™ OR gate to operate the faceplate Trip indicator LED.THREE POLE OPERATION:In applications where single pole tripping is not required this element provides a convenient method of collecting inputs toinitiate tripping of circuit breakers, the reclose element and breaker failure elements.SINGLE POLE OPERATION:This element must be used in single pole operation applications.In these applications this element is used to:• determine if a single pole operation should be performed• collect inputs to initiate three pole tripping, the recloser and breaker failure elements• collect inputs to initiate single pole tripping, the recloser and breaker failure elements• assign a higher priority to pilot aided scheme outputs than to exclusively local inputs.This element works in association with other L60 elements (see Chapter 8 for a complete description of single pole opera-tions) that must be programmed and in-service for successful operation. The necessary elements are: Recloser, BreakerControl, Open Pole Detector, and Phase Selector. The recloser must also be in the “Reset” state before a single pole tripcan be issued. Outputs from this element are also directly connected 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 to thiselement. In pilot-aided scheme applications (DUTT, PUTT, POTT, Hybrid POTT, and Directional Blocking) a timer can beused to delay the output decision until data from a remote terminal is received from communications facilities, to prevent athree pole operation where a single pole operation is permitted.• TRIP MODE: This setting is used to select the required mode of operation. If selected to “3 Pole Only” outputs for allthree phases are always set simultaneously. If selected to “3 Pole & 1 Pole” outputs for all three phases are set simul-taneously unless the phase selector or a pilot aided scheme determines the fault is single-phase-to-ground. If the faultis identified as being AG, BG or CG only the operands for the faulted phase will be asserted.• TRIP 3-POLE INPUT-1(6): This setting is used to select an operand representing a fault condition that is not desired toinitiate a single pole operation, e.g. phase undervoltage. Use a FlexLogic OR -gate if more than six inputs are required.• TRIP 1-POLE INPUT-1(6): Selects an operand representing a fault condition that is desired to initiate a single pole trip-and-reclose if the fault is single phase to ground, e.g. distance Zone 1. Use a FlexLogic™ OR -gate if more than sixinputs are required. The inputs do not have to be phase-specific as the phase selector 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. Thisoperand calls for a three-pole trip if any protection element configured under TRIP 1-POLE INPUT remains picked-up. TheOpen Pole Detector provides blocking inputs to distance elements, and therefore the latter will reset immediately afterthe TRIP 1-POLE operand is asserted. For other protection elements used in single-pole tripping, the user must ensurethey will reset immediately after tripping, otherwise the fact that they are still picked up will be detected as an evolvingfault and the relay will trip three-poles. For example, if high-set phase instantaneous overcurrent is used (TRIP 1-POLEINPUT X: “ PHASE IOC1 OP ”), then OPEN POLE OP ΦA shall be used for blocking Phase A of the Instantaneous Overcur-rent element. In this way, after tripping Phase A, the Phase A Instantaneous Overcurrent element is forced to reset.Phases B and C are still operational and can detect an evolving fault as soon as 8 ms after tripping Phase A. Neutraland negative-sequence instantaneous overcurrent elements shall be blocked from the OPEN POLE BLK N operandunless the pickup setting is high enough to prevent pickup during single-pole reclosing.• TRIP RECLOSE INPUT-1(6): Selects an operand representing a fault condition that is desired to initiate three polereclosing, e.g. Phase Distance Zone 1. Use a FlexLogic™ OR-gate if more than six inputs are required.• TRIP FORCE 3-POLE: Selects an operand that will force an input selected for single pole operation to produce a threepole operation. The AR DISABLED FlexLogic™ operand is the recommended value for this setting. Power system con-figurations or conditions which require such operations may be considered as well.NOTE