Areva MiCOM P441, Technical Manual

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P44x/EN AD/E44 Update Documentation
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MiCOM P441, P442 & P444
3.3 Platform software
To provide the internal interface between the settings database and each of the relay’s user
interfaces, i.e. the front panel interface and the front and rear communication ports, using
whichever communication protocol has been specified (Courier, Modbus, IEC60870-5-103;
DNP3 ,UCA2).
3.3.1 Record logging
…/… The relay maintains four logs: one each for up to 96 alarms (with 64 application alarms:
32 alarms in alarm status 1 and another group of 32 alarms in alarm staus 2 and 32 alarms
platform (see GC annex for mapping), 250 event records, 5 fault records and 5 maintenance
records
3.4.1 Overview - protection and control scheduling
…/… For the P441-442-444 feeder protection relay, the protection task is executed twice per
cycle, i.e. after every 24 samples for the sample rate of 48 samples per power cycle used
by the relay…/…
3.4.5 Disturbance Recorder
The disturbance recorder operates as a separate task from the protection and control task. It
can record the waveforms for up to 8 analogue channels and the values of up to 32 digital
signals. The recording time is user selectable up to a maximum of 10 seconds. The
disturbance recorder is supplied with data by the protection and control task once per cycle.
The disturbance recorder collates the data that it receives into the required length
disturbance record. It attempts to limit the demands it places on memory space by saving the
analogue data in compressed format whenever possible. This is done by detecting changes
in the analogue input signals and compressing the recording of the waveform when it is in a
steady-state condition. The compressed (with Kbus or ModBus only – IEC is not
compressed) disturbance records can be decompressed by MiCOM S1 which can also
store the data in COMTRADE format, thus allowing the use of other packages to view the
recorded data.
Since C1.x the disturbance files are no more compressed. This version manage the
disturbance task with 24 samples by cycle (since B1x & C1x). Maximum storage
capacity is equivalent to 28 events of 3sec which gives 84sec of duration max.