Fuse failFuse fail Line VoltageLine Bus Voltage LinereferencevoltageBus voltage52ANSI10000079-2-en.vsdSynchroCheckVHighBusSC > 50 – 120% of GblBaseSelBusVHighLineSC >50 – 120% of GblBaseSelLineVDiffSC < 0.02 – 0.50 p.u.PhaseDiffM < 5 – 90 degreesPhaseDiffA < 5 – 90 degreesFreqDiffM < 3 – 1000 mHzFreqDiffA < 1000 mHzANSI10000079 V2 EN-USFigure 102: Principle for the synchronism check function13.1.2.3 Energizing check M12310-3 v11The main purpose of the energizing check function is to facilitate the controlled re-connection ofdisconnected lines and buses to energized lines and buses.The energizing check function measures the bus and line voltages and compares them to bothhigh and low threshold values. The output is given only when the actual measured conditionsmatch the set conditions. Figure 103 shows two substations, where one (1) is energized and theother (2) is not energized. The line between CB A and CB B is energized (DLLB) from substation 1via the circuit breaker A and energization of station 2 is done by CB B energization check device forthat breaker DBLL. (or Both).1 2A BEnergizingCheckLine voltageBus voltageANSI10000078-4-en.vsdVLiveBusEnerg > 50 - 120 % of GblBaseSelBusVLiveLineEnerg > 50 - 120 % of GblBaseSelLineVDeadBusEnerg < 10 - 80 % of GblBaseSelBusVDeadLineEnerg < 10 - 80 % of GblBaseSelLineVMaxEnerg < 50 - 180 % of GblBaseSelBus and/orGblBaseSelLineANSI10000078 V4 EN-USFigure 103: Principle for the energizing check functionSection 13 1MRK 511 358-UUS AControl256Application manual
