Svantek SVAN 979, User Manual

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SVAN 979 User Manual
External type trigger
When External is selected, recording starts from the external signal on the I/O
socket. In this case, it is necessary to set up the I/O Mode parameter as
Digital In ( path: < Menu> / Instrument / Multifunction I/O ).
After triggering, recording will last Recording Time (unless the measurement is
stopped earlier) and if during this time new external trigger appears the
instrument will prolong recording for another
Recording Time .
Integr. Period type trigger
When the Integr. Period trigger is selected, recording is triggering every time
the measurement starts and lasts Recording Time (unless the measurement is
stopped earlier). If the triggering condition appears during recording (when
Integration Period is shorter than Recording Time ) from this moment
recording will be continued for another Recording Time and so on.
Note: When recording is waiting for the External or Integration
Period
trigger the “trigger” icon appears alternatively with the „wave”
icon.
Source result
Only one measured result can be used as a trigger source ( Source ) for checking the trigger condition in the
Level Meter mode, namely the instantaneous RMS from the first profile (with appropriate filter and detector),
which is denoted here as Leq(1) in the sound mode and RMS(1) in the vibration mode. This position cannot be
changed.
This result averaged for the Trigger Period is compared with the Level value with the step defined by the
Trigger Period .
Threshold level
The threshold level for the logger trigger
(
Level ) can be set with 1 dB steps in the
range from 24 dB to 136 dB in the sound
mode and from 1 mm/s
2
(60 dB) to 10 km/s
2
(200 dB) in the vibration mode.
The Trigger Period parameter defines the time interval of checking the trigger
conditions. This parameter can be set as: Log. Step (same as Logger Step
value), 0.5ms , 100.0ms and 1s .
The Recording Time parameter defines the time of signal recording after every
trigger. The available values can be selected from 1s to 8h or Inf (recording will
last until measurement stop).
When Pre Trigger position is switched on the signal starts to be recorded
before the trigger. The period of such recording depends on the sample
frequency. For 48 kHz the period is 1s, for 24 kHz - 2 s, for 12 kHz - 4s.