ABB REG316 4 Series Operating Instructions Manual page 380

ABB Switzerland Ltd REG 316*4 1MRB520049-Uen / Rev. F
E. Setting instructions
General:
The disturbance recorder function may only be configured
once for each set of parameters.
The special "disturbance recorder" function serves to record cur-
rent and voltage waveforms and measured function variables
when a protection function picks up. A battery buffered 64 kByte
memory is provided for this purpose, which enables 9 analogue
and 8 binary signals to be recorded within a maximum of approx.
5 seconds.
To ensure that the memory is not filled by useless data, record-
ing only takes place after a starting signal (trigger signal). Each
time a start signal is generated, the data are recorded for a pre-
defined time and saved as an "event". Thus depending on the
definitions of the relevant times, the memory has capacity for
between 1 and approx. 56 events.
To enable the circumstances leading up to an event and also the
responses after an event to be studied, an event comprises
three parts, the pre-event data (recorded before the start signal),
the data of the event itself and the post-event data. The dura-
tions of these three periods can be independently defined.
How the data prior to an event is obtained requires a little more
explanation. Data are continuously recorded from the instant the
programming of the perturbograph function has been completed.
They are fed into a ring shift register, the older data at the
beginning being overwritten as soon as the register is full. This
cyclic overwriting of the ring register continues until a start signal
initiates the recording of an event (trigger signal). Thus the cir-
cumstances immediately prior to the actual event are available in
the ring register.
The duration of the record of the actual event is determined by
the tripping signal (trigger signal), i.e. recording continues for as
long as it is active (recording mode A). If the tripping signal is
very short, recording lasts for at least 100 milliseconds and if it is
very long, recording is discontinued upon reaching the maximum
duration (set event time). A second mode of operation is also
provided (recording mode B), for which the duration of recording
always equals the set event time regardless of the duration of
the trigger signal.
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