13.10.5 Technical dataTable 366:technical dataFunction ValueBuffer capacity Maximum number of analog inputs 30Maximum number of disturbance reports 10013.11 Disturbance recorder13.11.1 IntroductionThe Disturbance recorder function supplies fast, complete and reliable informationabout disturbances in the power system. It facilitates understanding systembehavior and related primary and secondary equipment during and after adisturbance. Recorded information is used for different purposes in the shortperspective (for example corrective actions) and long perspective (for examplefunctional analysis).The Disturbance recorder acquires sampled data from selected analog- and binarysignals connected to the Disturbance report function (maximum 40 analog and 96binary signals). The binary signals available are the same as for the event recorderfunction.The function is characterized by great flexibility and is not dependent on theoperation of protection functions. It can record disturbances not detected byprotection functions. Up to ten seconds of data before the trigger instant can besaved in the disturbance file.The disturbance recorder information for up to 100 disturbances are saved in theIED and the local HMI is used to view the list of recordings.13.11.2 Principle of operationDisturbance recording (DR) is based on the acquisition of binary and analogsignals. The binary signals can be either true binary input signals or internal logicalsignals generated by the functions in the IED. The analog signals to be recorded areinput channels from the Transformer Input Module (TRM), Line Differentialcommunication Module (LDCM) through the Signal Matrix Analog Input (SMAI)and possible summation (Sum3Ph) function blocks and some internally derivedanalog signals. For details, refer to section "Disturbance report DRPRDRE".Disturbance recorder collects analog values and binary signals continuously, in acyclic buffer. The pre-fault buffer operates according to the FIFO principle; olddata will continuously be overwritten as new data arrives when the buffer is full.The size of this buffer is determined by the set pre-fault recording time.Section 13 1MRK 505 208-UEN BMonitoring532Technical reference manual
