Copyright © Sigicom AB 2020
18
3.2.3.
Transient Recording
When an instantaneous value exceeds the selected trigger level for any of
the three channels, a transient recording of all three channels is initiated.
A transient recording can also be initiated via the Menu of the graphical
user interface (“Manual trigger”, see section 5.8).
Each channel has a trigger level which can be set through INFRA Net or
the graphical user interface. Their maximum and minimum values depend
on the selected measurement standard. The trigger levels are common for
all standards.
Note!
It is very important to set to an adequate trigger level. When set too
high, there will be no recordings. If, on the other hand, the level is set too
low, there will be lots of (continuous) triggering/recordings, which would
lead to:
•
Increase of battery consumption.
•
Lots of data storage on memory card.
•
High data transfer rate/cost.
The length of the recording is 1 second before the trigger point plus an
adjustable time between 1 and 40 seconds. The adjustable time is referred
to as “Record time” in the graphical user interface and “Transient time” in
INFRA Net.
For each maximum value (“EVT” in the graphical user interface) of the
transients, a frequency is estimated using a zero-crossing algorithm, see
description of this in section 3.2.2.
3.2.4.
Overload Handling
If analog or digital overload occurs in one or more samples during an
interval period, the interval value of that interval period is tagged with an
overload flag. Similarly, if analog or digital overload occurs in one or
more samples during recording of a transient, the corresponding transient
will be tagged with an overload flag. In this way INFRA Net can indicate
possible overload in its interval and transient data reports.
Overload is indicated in the display with a “>” before the value.
