Disturbance recorderOperationM: Analog channel M is to be recorded by the disturbance recorder (Enabled)or not (Disabled).If OperationM = Disabled, no waveform (samples) will be recorded and reported in graph.However, Trip value, pre-fault and fault value will be recorded and reported. The inputchannel can still be used to trig the disturbance recorder.If OperationM = Enabled, waveform (samples) will also be recorded and reported ingraph.Event recorderEvent recorder (ER) function has no dedicated parameters.Trip value recorderZeroAngleRef: The parameter defines which analog signal that will be used as phase anglereference for all other analog input signals. This signal will also be used for frequencymeasurement and the measured frequency is used when calculating trip values. It issuggested to point out a sampled voltage input signal, for example, a line or busbar phasevoltage (channel 1-30).Sequential of eventsfunction has no dedicated parameters.14.6.3.5 ConsiderationThe density of recording equipment in power systems is increasing, since the number ofmodern IEDs, where recorders are included, is increasing. This leads to a vast number ofrecordings at every single disturbance and a lot of information has to be handled if therecording functions do not have proper settings. The goal is to optimize the settings in eachIED to be able to capture just valuable disturbances and to maximize the number that ispossible to save in the IED.The recording time should not be longer than necessary (PostFaultrecT and TimeLimit).• Should the function record faults only for the protected object or cover more?• How long is the longest expected fault clearing time?• Is it necessary to include reclosure in the recording or should a persistent faultgenerate a second recording (PostRetrig)?Minimize the number of recordings:• Binary signals: Use only relevant signals to start the recording that is, protection trip,carrier receive and/or pickup signals.• Analog signals: The level triggering should be used with great care, since unfortunatesettings will cause enormously number of recordings. If nevertheless analog input1MRK 505 337-UUS - Section 14Monitoring427Application manual
