4.5 Voltage protection4.5.1 Three-phase overvoltage protection PHPTOV4.5.1.1 IdentificationFunction description IEC 61850identificationIEC 60617identificationANSI/IEEE C37.2device numberThree-phase overvoltage protection PHPTOV 3U> 594.5.1.2 Function blockGUID-871D07D7-B690-48FD-8EA1-73A7169AE8BD V1 ENFigure 248: Function block4.5.1.3 FunctionalityThe three-phase overvoltage protection PHPTOV is applied on power systemelements, such as generators, transformers, motors and power lines, to protect thesystem from excessive voltages that could damage the insulation and causeinsulation breakdown. The three-phase overvoltage function includes a settablevalue for the detection of overvoltage either in a single phase, two phases or threephases.PHPTOV includes both definite time (DT) and inverse definite minimum time(IDMT) characteristics for the delay of the trip.The function contains a blocking functionality. It is possible to block functionoutputs, timer or the function itself, if desired.4.5.1.4 Operation principleThe function can be enabled and disabled with the Operation setting. Thecorresponding parameter values are "On" and "Off".The operation of the three-phase overvoltage protection can be described using amodule diagram. All the modules in the diagram are explained in the next sections.Section 4 1YHT530004D05 DProtection functions466 615 seriesTechnical Manual
