P12x/EN T/Eb6 - Schneider - error

Application GuideP12x/EN AP/Eb6MiCOM P120/P121/P122/P123 Page 75/7833. ROLLING AND PEAK VALUE DEMANDS (P122 & P123 ONLY)MiCOM P122 and P123 relays can store the 3 phases rolling average and maximumsubperiod values. The description and principle of calculation are presented hereafter.33.1 Rolling demandCalculation of the rolling demand value for IA, Ib and IC currents is done the following way:• Calculation of the average of the RMS values on a "Rolling Sub Period" period.The width of the period "Rolling Sub Period" can be set under the "RECORDS/RollingDemand/Sub Period" menu.Setting range: from 1 to 60 minutes.• Storage of these values in a sliding window.Calculation of the average of these average values (sliding window values) on the number of"Num of Sub Periods" periods.The number of Sub Period "Num of Sub Periods" can be set under the "RECORDS/RollingDemand/Num of Sub Per" menu.Setting range: from 1 to 24.• Display of the first result under the MEASUREMENTS menu only after the storage of"Num of Sub Periods" periods. The 3 phases Rolling average value are displayed:Rolling Average IA RMSRolling Average IB RMSRolling Average IC RMS−The calculation is reset either via the front operator interface (Key c) without entering apassword, or by a remote command.NOTE:In case of loss of power supply the rolling demand are not stored.A modification of the settings (either "Rolling Sub Period" or "Num ofSub Periods" parameter) reset the calculation.Example:Sub Period = 5 mnNum of Sub Period = 2At the end of the Sub Period 2:Rolling average value = (average value 1 + average value 2)/2At the end of the Sub Period 3:New Rolling average value = (average value 2 + average value 3)/2