Sefram
CHAPITRE 3. GETTING STARTED
F
IGURE
3.16 : Combination of conditions
In the example above, if one of the defined conditions is true, then recording is triggered
(1)
. If the voltage of
analog channel 1 is less than 50V OR if the RMS value of channel 2 is greater than 25V for 100 ms, then recording
is triggered
(2).
3.7.6
Pre-trigger
When the start condition is a trigger or a combination of triggers, the user can configure a pre-trigger. This corres-
ponds to a number of samples or a time to be recorded before the trigger condition. The user can configure the
duration of this window
(1).
Please note that if the event before the pre-trigger duration has been met, its duration
will be shorter unless the inhibit option
(2)
is enabled.
Example 60s pre-trigger without inhibit
If the event starts at 15s, recording will begin and the pre-trigger will only be 15s long.
Example 60s pre-trigger with inhibit
If the event occurs after 15s, recording will not start. The event must occur again after 60s to be taken into
account ; recording will start and the pre-trigger will be 60s as defined by the user.
F
IGURE
3.17 : Pre-trigger
By activating Inhibit
(2)
, triggering is ignored if the pre-trigger window is not full :
DAS
User manual
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