CHAPTER 5: SETTINGS GROUPED ELEMENTSG30 GENERATOR PROTECTION SYSTEM – INSTRUCTION MANUAL 5-2195Table 5-34: Operating and polarizing signalsMode of operation• When the function is “Disabled” or the operating current is below 5% × CT nominal, the element output is logic “0”• When the function is “Enabled,” the operating current is above 5% × CT nominal, and the polarizing voltage is abovethe PRODUCT SETUP DISPLAY PROPERTIES VOLTAGE CUT-OFF LEVEL value, the element output is dependent on thephase angle between the operating and polarizing signals:– The element output is logic “0” when the operating current is within polarizing voltage ±90°– For all other angles, the element output is logic “1”• Once the voltage memory has expired, the phase overcurrent elements under directional control can be set to block ortrip on overcurrent as follows:– When BLOCK WHEN V MEM EXP is set to “Yes,” the directional element blocks the operation of any phaseovercurrent element under directional control when voltage memory expires– When BLOCK WHEN V MEM EXP is set to “No,” the directional element allows tripping of phase overcurrent elementsunder directional control when voltage memory expiresIn all cases, directional blocking is permitted to resume when the polarizing voltage becomes greater than the polarizingvoltage threshold.SettingsPHASE DIR 1 FUNCTION — This setting enables and disables the phase directional overcurrent protection element.PHASE DIR 1 SIGNAL SOURCE — This setting is used to select the source for the operating and polarizing signals. Theoperating current for the phase directional element is the phase current for the selected current source. The polarizingvoltage is the line voltage from the phase VTs, based on the 90° or quadrature connection and shifted in the leadingdirection by the element characteristic angle (ECA).PHASE DIR 1 BLOCK — Assertion of the operand assigned to this setting blocks operation of the phase directionalovercurrent element.PHASE DIR 1 ECA — This setting specifies the element characteristic angle, that is, the angle by which the polarizing voltageis shifted in the leading direction to achieve dependable operation. In the design of the UR-series elements, a block isapplied to an element by asserting logic 1 at the blocking input. Program the phase directional overcurrent element usingthis setting so that the output is logic 1 for current in the non-tripping direction.PHASE DIR 1 POL V THRESHOLD — This setting is used to establish the minimum level of voltage for which the phase anglemeasurement is reliable. The setting is based on VT accuracy.PHASE DIR 1 BLOCK WHEN V MEM EXP — This setting is used to select the required operation upon expiration of voltagememory. When set to "Yes," the directional element blocks the operation of any phase overcurrent element underdirectional control, when voltage memory expires. When set to "No," the directional element allows tripping of phaseovercurrent elements under directional control.PHASE DIR 1 EVENTS — This setting enables and disables the logging of phase directional overcurrent events in thesequence of events recorder.Phase Operating signal Polarizing signal V polABC phase sequence ACB phase sequenceA angle of IA angle of VBC × (1∠ECA) angle of VCB × (1∠ECA)B angle of IB angle of VCA × (1∠ECA) angle of VAC × (1∠ECA)C angle of IC angle of VAB × (1∠ECA) angle of VBA × (1∠ECA)
