GE Power ManagementL90 Line Differential Relay5-655 SETTINGS 5.5 GROUPED ELEMENTS5PHS DIST Z2 VOLT LEVEL:This setting is relevant for applications on series-compensated lines, or in general, if series capacitors are located betweenthe relaying point and a point for which the zone shall not overreach. For plain (non-compensated) lines, this setting shallbe set to zero. Otherwise, the setting is entered in per unit of the phase VT bank configured under the DISTANCE SOURCE.See the THEORY OF OPERATION chapter for more details, and the APPLICATION OF SETTINGS chapter for informationon how to calculate this setting for applications on series compensated lines.PHS DIST Z2 DELAY:This setting enables the user to delay operation of the distance elements and implement a stepped distance protection.The distance element timer applies a short dropout delay to cope with faults located close to the zone boundary when smalloscillations in the voltages and/or currents could inadvertently reset the timer.PHS DIST Z2 BLK:This setting enables the user to select a FlexLogic™ operand to block a given distance element. VT fuse fail detection isone of the applications for this setting.Figure 5–26: PHASE DISTANCE Z2 OP SCHEMEFLEXLOGIC OPERANDSFLEXLOGIC OPERANDFLEXLOGIC OPERANDSSETTINGPH DIST Z2 PKP ABPH DIST Z2 PKP BCPH DIST Z2 PKP CAPH DIST Z2 OP ABPH DIST Z2 OP BCPH DIST Z2 OP CAPH DIST Z2 OPPHS DIST Z2DELAY:20 msec20 msec20 msec 837020A4.CDRORtttPKPPKPPKP
