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INTAB Interface-Teknik AB
4.3
Trig Window - Pre/Post Trig Recording
The PC-Logger 3150 is often used as a trouble-shooter to catch transient
events. The area of interest is often the time just prior to the fault condition and
then a certain amount after.
The fault condition would trigger the stop.
The time before (pre) and after (post) this event constitute the "Trig Window".
Windows are programmed as a parameter in the "/RECORD/PARAMETERS/"
section of the "PC-Logger 3100 PC soft". It requires "circulating" memory
which is consequently automatically switched on.
The window is programmed as a pre-trig time and a total time. The post-trig
time will of course be the difference between the total and pre-trig time.
The recording, started with the trig-window active, will first go through a "pre-
amble", corresponding to the pre-trig period, when it is insensitive to stop
trigs. After the pre trig period it will register a stop-trig when it occurs and
then continue for the post-trig period before stopping.
The recording can be left to run for very long periods thanks to the
"circulating" or endless memory. The window with correct time will just "slide
along" and always be there for transferral after the stop-trig and post trig
period.
The entire recording can, of course, be transferred to computer. It is, however,
usually more practical to just transfer the window. The software will give you
the choice!
When the transferred "window" is presented as graphs, a vertical line
indicating where the stop-trig occurred, is shown on the computer screen.
