The Trip value recorder calculates the values of all selected analog input signalsconnected to the Disturbance report function. The result is magnitude and phaseangle before and during the fault for each analog input signal.The trip value recorder information is available for the disturbances locally in theIED.The trip value recorder information is an integrated part of the disturbance record(Comtrade file).13.10.2 Function blockThe Trip value recorder has no function block of it’s own.13.10.3 Signals13.10.3.1 Input signalsThe trip value recorder function uses analog input signals connected to A1RADRto A3RADR (not A4RADR).13.10.4 Operation principleTrip value recorder calculates and presents both fault and pre-fault amplitudes aswell as the phase angles of all the selected analog input signals. The parameterZeroAngleRef points out which input signal is used as the angle reference.When the disturbance report function is triggered the sample for the faultinterception is searched for, by checking the non-periodic changes in the analoginput signals. The channel search order is consecutive, starting with the analoginput with the lowest number.When a starting point is found, the Fourier estimation of the pre-fault values of thecomplex values of the analog signals starts 1.5 cycle before the fault sample. Theestimation uses samples during one period. The post-fault values are calculatedusing the Recursive Least Squares (RLS) method. The calculation starts a fewsamples after the fault sample and uses samples during 1/2 - 2 cycles depending onthe shape of the signals.If no starting point is found in the recording, the disturbance report trig sample isused as the start sample for the Fourier estimation. The estimation uses samplesduring one cycle before the trig sample. In this case the calculated values are usedboth as pre-fault and fault values.The name of the analog input signal that appears in the Trip value recorder functionis the user-defined name assigned when the IED is configured. The same name isused in the Disturbance recorder function .1MRK 502 034-UEN - Section 13Monitoring417Technical Manual
