GE Multilin G60 Generator Protection System 5-2075 SETTINGS 5.6 GROUPED ELEMENTS55.6.10 GENERATOR UNBALANCEPATH: SETTINGS GROUPED ELEMENTS SETTING GROUP 1(6) GENERATOR UNBALANCEThe generator unbalance element protects the machine from rotor damage due to excessive negative-sequence current.The element has an inverse time stage which is typically used for tripping and a definite time stage typically used for alarmpurposes. The inverse time stage operating characteristic is defined by the following equation:where Inom is the generator rated current and K is the negative-sequence capability constant nor-mally provided by the generator manufacturer.• GEN UNBAL INOM: This setting is the rated full load current of the machine.• GEN UNBAL STG1 PICKUP: This setting defines the pickup of the stage 1 element expressed as a percentage of thenominal current as specified by GEN UNBAL INOM setting. It is typically set at the maximum continuous negativesequence current rating of the machine.• GEN UNBAL STG1 K-VALUE: This setting is the negative sequence capability constant. This value is normally pro-vided by the generator manufacturer (refer to ANSI C50.13 for details).• GEN UNBAL STG1 TMIN: This is the minimum operate time of the stage 1 element. The stage will not operate beforethis time expires. This is set to prevent false trips for faults that would be cleared normally by system protections.• GEN UNBAL STG1 TMAX: This is the maximum operate time of the stage 1 element. This setting can be applied tolimit the maximum tripping time for low level unbalances. GENERATOR UNBALANCEGENERATOR UNBALFUNCTION: DisabledRange: Disabled, EnabledMESSAGE GEN UNBAL SOURCE:SRC 1Range: SRC 1, SRC 2, SRC 3, SRC 4MESSAGE GEN UNBAL INOM:0.800 puRange: 0.000 to 1.250 pu in steps of 0.001MESSAGE GEN UNBAL STG1PICKUP: 8.00%Range: 0.00 to 100.00% in steps of 0.01MESSAGE GEN UNBAL STG1K-VALUE: 1.00Range: 0.00 to 100.00 in steps of 0.01MESSAGE GEN UNBAL STG1 TMIN:0.250 sRange: 0.000 to 50.000 s in steps of 0.001MESSAGE GEN UNBAL STG1 TMAX:600.00 sRange: 0.0 to 1000.0 s in steps of 0.1MESSAGE GEN UNBAL STG1K-RESET: 240.00 sRange: 0.0 to 1000.0 s in steps of 0.1MESSAGE GEN UNBAL STG2PICKUP: 3.0%Range: 0.00 to 100.00% in steps of 0.01MESSAGE GEN UNBAL STG2 PKPDELAY: 5.0 sRange: 0.0 to 1000.0 s in steps of 0.1MESSAGE GEN UNBAL BLK:OffRange: FlexLogic operandMESSAGE GEN UNBAL TARGET:Self-ResetRange: Self-reset, Latched, DisabledMESSAGE GEN UNBAL EVENTS:DisabledRange: Enabled, DisabledT KI2 I nom⁄( )2---------------------------=
