12.1.7.4 Energizing checkVoltage values are measured in the IED and are available for evaluation by theSynchronism check function.The function measures voltages on the busbar and the line to verify whether they are liveor dead. To be considered live, the value must be above 80% of set UBase selected forGblBaseSelBus or GblBaseSelLine and to be considered dead it must be below 40% of setUBase selected forGblBaseSelBus or GblBaseSelLine.The frequency on both sides of the circuit breaker is also measured. The frequencies mustnot deviate from the rated frequency more than +/-5Hz.The Energizing direction can be selected individually for the Manual and the Automaticfunctions respectively. When the conditions are met the outputs AUTOENOK andMANENOK respectively will be activated if the fuse supervision conditions are fulfilled.The output signal can be delayed independently for MANENOK and AUTOENOKconditions. The Energizing direction can also be selected by an integer input AENMODErespective MENMODE, which for example, can be connected to a Binary to Integerfunction block (B16I). Integers supplied shall be 1=off, 2=DLLB, 3=DBLL and 4= Both.Not connected input with connection of INTZERO output from Fixed Signals(FIXDSIGN) function block will mean that the setting is done from Parameter Settingtool. The active position can be read on outputs MODEAEN resp MODEMEN. Themodes are 0=OFF, 1=DLLB, 2=DBLL and 3=Both.The inputs BLOCK and BLKENERG are available for total block of the completeSESRSYN (25) function respective block of the Energizing check function. TSTENERGwill allow testing of the function where the fulfilled conditions are connected to a separatetest output.12.1.7.5 Fuse failure supervisionExternal fuse failure signals or signals from a tripped fuse switch/MCB are connected tobinary inputs that are configured to the inputs of SESRSYN (25) function in the IED.Alternatively, the internal signals from fuse failure supervision can be used whenavailable. There are two alternative connection possibilities. Inputs labelled OK must beconnected if the available contact indicates that the voltage circuit is healthy. Inputslabelled FF must be connected if the available contact indicates that the voltage circuit isfaulty.The VB1OK/VB2OK and VB1FF/VB2FF inputs are related to the busbar voltage and theVL1OK/VL2OK and VL1FF/VL2FF inputs are related to the line voltage. Configurethem to the binary input or function outputs that indicate the status of the external fusefailure of the busbar and line voltages. In the event of a fuse failure, the energizing checkfunction is blocked. The synchronism check function requires full voltage on both sides,thus no blocking at fuse failure is needed.1MRK 502 048-UUS A Section 12Control355Technical manual
