Hioki LR8431-20 - Setting Criteria for Pre-Trigger Recording (Pre-Trig)

4.1 Setting Criteria to Start and Stop Recording
72
Select the [Start] or [Start&Stop] trigger timing setting
to record waveforms both before and after trigger
event
s.
However, pre-trigger recording is disabled when [Stop]
trigger timing
is
selected.
Make the setting on the [Trig & Alm] screen.
Setting Criteria for Pre-Trigger Recording (Pre-Trig)
T
For the [Pre-Trig] setting, specify the time (or
number of days) to record before a trigger event.
To record waveforms after a trigger event, simply spec-
ify a recording time that is longer than the pre-trigger
recording time.
Difference between [Waiting for pre-trigger] and [Wait-
ing for trigger]
When measurement is started, the specified pre-trigger
length is recorded. This period is indicated as the [Waiting
for pre-trigger].
After the specified pre-trigger length has been recorded, the
period indicated as [Waiting for trigger] continues until a
trigger occurs.
During the [Waiting for pre-trigger] period, trigger events
are not recognized even when the trigger criteria are met.
The maximum settable
time span is displayed.
Change 1’s digit
Change 10’s digit
T
Pre-Tirg: 15 minutes
Recording
length
(10 minutes)
Recording ends
at trigger event
Recording Time shorter than 
Pre-Trigger Time
Recording Time longer than 
Pre-Trigger Time
T
Pre-Tirg: 5 minutes
Recording
length
(15 minutes)
Records both before
and after trigger event
Recording ends
when recording
length has passed
Pre-Trigger vs. Recording Time