GE Multilin T60 Transformer Protection System 5-775 SETTINGS 5.4 SYSTEM SETUP5Figure 5–19: DISTURBANCE DETECTOR LOGIC DIAGRAMThe disturbance detector responds to the change in currents of twice the current cut-off level. The default cut-off thresholdis 0.02 pu; thus by default the disturbance detector responds to a change of 0.04 pu. The metering sensitivity setting (PROD-UCT SETUP DISPLAY PROPERTIES CURRENT CUT-OFF LEVEL) controls the sensitivity of the disturbance detectoraccordingly.EXAMPLE USE OF SOURCES:An example of the use of sources is shown in the diagram below. A relay could have the following hardware configuration:This configuration could be used on a two-winding transformer, with one winding connected into a breaker-and-a-half sys-tem. The following figure shows the arrangement of sources used to provide the functions required in this application, andthe CT/VT inputs that are used to provide the data.INCREASING SLOT POSITION LETTER -->CT/VT MODULE 1 CT/VT MODULE 2 CT/VT MODULE 3CTs VTs not applicable827092A3.CDRSOURCE 1CURRENT PHASORPRODUCT SETUP/DISPLAYPROPERTIES/CURRENTCUT-OFF LEVELPRODUCT SETUP/DISPLAYPROPERTIES/CURRENTCUT-OFF LEVELPRODUCT SETUP/DISPLAYPROPERTIES/CURRENTCUT-OFF LEVELSOURCE 2CURRENT PHASORSOURCE 6CURRENT PHASORACTUALSETTINGSETTINGSETTINGACTUALACTUALFLEXLOGIC OPERANDFLEXLOGIC OPERANDFLEXLOGIC OPERANDI_1I_1I_1SRC 1 50DD OPSRC 2 50DD OPSRC 6 50DD OPI_2I_2I_2I_0I_0I_0ORORORWhere ’ is 2 cycles oldIWhere ’ is 2 cycles oldIWhere ’ is 2 cycles oldII I_1 - _1’ >2*CUT-OFFI I_1 - _1’ >2*CUT-OFFI I_1 - _1’ >2*CUT-OFFI I_2 - _2’ >2*CUT-OFFI I_2 - _2’ >2*CUT-OFFI I_2 - _2’ >2*CUT-OFFI I_0 - _0’ >2*CUT-OFFI I_0 - _0’ >2*CUT-OFFI I_0 - _0’ >2*CUT-OFF
