Waveform Storage - Siemens 7SR51 Device Manual

Waveform Storage

3.6.2
Waveform records plot the instantaneous magnitude of each analogue input channel, the status of each
binary input, binary output, virtual I/O and LED. The values are recorded at each sampling point used by the
relay software.
Each recorded analogue waveform displays an input identifier and the instantaneous values at both cursor
positions (user variable).
Each binary waveform displays the input/output number and the initiating condition(s) e.g. external input or
protection element.
The latest 20 records can be stored, the most recent is waveform 1.
Waveform records are stored in real time into RAM memory and then archived to non-volatile memory as a
background task during quiescent periods, (see
seconds of waveform data allocated to records of 10 s, 5 s, 2 s or 1 s. When the waveform archive buffer is
full, the triggering of a new waveform record causes the oldest record to be overwritten.
NOTE
i
i
If a new record is triggered before the oldest record in RAM is archived, data can be lost. If records are
expected in rapid succession, such as with short deadtime autoreclose, this setting should be selected to
suit.
20 records are stored in the archive regardless of their duration.
Stored waveforms can be deleted from the relay fascia using the Data Storage > Clear Waveforms
setting or from Reydisp.
Relay waveform storage is triggered (initiated) by user selected relay operations, from the relay fascia (Wave-
form Storage > Trigger Waveform), from a suitably programmed binary input or from the data comms
channel(s). An output is provided to indicate when a new record has been stored.
The IEC 61850 implementation supports the file transfer model to transfer the waveform records in
COMTRADE format with a MMS file directory name /COMTRADE/*.
Waveform Storage Settings
Parameter: Waveform Storage > Function Storage
•
Default Setting:
Waveform storage is triggered from operation of any of the selected protection or control elements.
Waveform storage can also be triggered from the relay fascia, from a suitably programmed binary input
or via the data comms channel(s).
Parameter: Waveform Storage > Pre-Trigger Storage
•
Default Setting:
The percentage of waveform storage prior to waveform triggering is user configurable e.g. for a 1 second
waveform record the default setting displays 500 ms of pre-fault trigger waveforms and 500 ms of post-
fault trigger waveforms.
Parameter: Waveform Storage > Record Duration
•
Default Setting:
The duration of each stored record is 1 s, 2 s, 5 s or 10 s.
If records are expected in rapid succession, such as with short deadtime autoreclose, this setting should
be selected to suit.
Reyrolle 7SR5, Overcurrent Protection Device, Device Manual
C53000-G7040-C014-1, Edition 11.2019
3.2 Device Configuration ). The RAM has a total capacity of 10
Device Functionality
3.6 Data Storage
113