Recording Times - ABB REC 561 User Manual

1MRK 580 132-XEN
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2 Recording times

Disturbance report - Introduction
The recording times are valid for the whole Disturbance Report. The Dis-
turbance Recorder and the Event Recorder register disturbance data and
events during tRecording, the total recording time. But indications are
only registered during the fault time.
The total recording time, tRecording, of a recorded disturbance is:
tRecording = tPre + tFault + tPost, or tPre + tLim, depending on which
criterion stops the current disturbance recording.
tPre
Pre-fault Fault
Fig. 2 Recording times relationship.
The different time periods are described below:
Period Is the ...
tPre Pre-fault recording time. More correctly it should be called pre-
triggering time, because it consists of not only a pre-fault time
but also the operating time for the trigger itself.
tFault Fault time of the recording. The fault time cannot be set and
continues as long as any valid trigger condition, binary or ana-
logue, persists (unless limited by tLim the limit time, see
below).
tPost Post-fault recording time. When all activated triggers during the
fault time are reset, the current disturbance recording continues
according to the set post-fault time.
tLim Limit time, which is the maximum recording time after the dis-
turbance recording was triggered. The limit time is used to elim-
inate the consequences of a faulty trigger that does not reset
within a reasonable time interval. It limits the maximum record-
ing time of a recording and prevents subsequent overwriting of
already stored disturbances.
ABB Network Partner AB
Version 1.0-00
tLim
tPost
Post-fault
(X80132-2)