This App will be useful to Protection Engineers,Commissioning Engineers and Design Engineers.For 51 and 51N protection , there are different Time current characteristics as per IEC ,IEEE and ANSI like IEC Normal Inverse,IEC Very Inverse,IEC Extreme inverse.The tripping time varies depending on the TCC,TMS , Fault current and Ip setting in the relay.With this App one can find out the tripping time of the relay for a particular Fault Current .TMS also can be calculated for a given tripping time.