Sepam - HV/MV Protection and control units (ENG) - Trinet

Definition of symbolsThis sheet gives the meaning of the symbols usedin the different block diagrams in the control andmonitoring function data sheets.c "falling": delays the disappearance of a data item for a time T.X 0 t SLogic functionsc "OR"XTXY≥1SZEquation: S = X + Y + ZSPulse processingc “Rising”: creates a short pulse (1 cycle) each time a data item appears.c "AND"XYZ&SXXSEquation: S = X.Y.Zc exclusive "Or"SXYZ=1Sc “Falling”: creates a short pulse (1 cycle) each time a data item disappears.XSS = 1 if one and only 1 input is set to 1(S = 1 if X + Y + Z = 1)c ComplementThese functions are capable of usingcomplementary data.XSXSN.B. The disappearance of a data item may be caused by the loss of auxiliarypower.Bistable functionThe bistables are used to store data (e.g. protection output latching).Equation: S = X ( S=1 if X=0 )SR10BTime delaysTwo types of time delays:c "rising": delays the appearance of a data itemfor a time T,SXt0 SRBXSTEquation: B = S + R.BPlease noteThe status of data stored by the bistables is saved in Sepam in the eventof power failures.2 Control and monitoring functions