12.8.3 Signals12.8.3.1 Input signalsThe trip value recorder function uses analog input signals connected to A1RADR toA3RADR (not A4RADR).12.8.4 Operation principleTrip value recorder calculates and presents both fault and pre-fault magnitudes as well asthe phase angles of all the selected analog input signals. The parameter ZeroAngleRefpoints out which input signal is used as the angle reference.When the disturbance report function is triggered the sample for the fault interception issearched for, by checking the non-periodic changes in the analog input signals. Thechannel search order is consecutive, starting with the analog input with the lowest number.When a fault interception point is found, the Fourier estimation of the pre-fault values ofthe complex values of the analog signals starts 1.5 cycle before the fault sample. Theestimation uses samples during one period. The post-fault values are calculated using theRecursive Least Squares (RLS) method. The calculation starts a few samples after thefault sample and uses samples during 1/2 - 2 cycles depending on the shape of the signals.If no starting point is found in the recording, the disturbance report trig sample is used asthe start sample for the Fourier estimation. The estimation uses samples during one cyclebefore the trig sample. In this case the calculated values are used both as pre-fault and faultvalues.The name of the analog signal that appears in the Trip value recorder function is the user-defined name assigned when the IED is configured. The same name is used in theDisturbance recorder function .The trip value record is stored as a part of the disturbance report information (LMBRFLO)and managed in PCM600 or via the local HMI.12.8.5 Technical dataTable 394:DRPRDRE technical dataFunction ValueBuffer capacity Maximum number of analog inputs 30Maximum number of disturbance reports 100Section 12 1MRK 511 287-UUS AMonitoring494Technical manual
