61000-4-30©IEC:2000–3–CONTENTSPagesFOREWORD.....................................................................................................5INTRODUCTION.................................................................................................7Clause1Scope...........................................................................................................92Normativereferences........................................................................................93Definitions.....................................................................................................114General........................................................................................................154.1Classesofperformance...........................................................................154.2Electricalvaluestobemeasured...............................................................174.3Measurementaggregationovertime...........................................................174.4Flaggingconcept....................................................................................174.5Measurementaggregationalgorithm...........................................................195Powerqualityparameters.................................................................................195.1Powerfrequency.....................................................................................195.2Magnitudeofthesupplyvoltage................................................................215.3Flicker..................................................................................................235.4Supplyvoltagedipsandswells..................................................................235.5Voltageinterruptions...............................................................................285.6Transientovervoltages.............................................................................285.7Supplyvoltageunbalance..................................................
