Svantek SV 973, User Manual

Page: 41 / 212

SVAN 973 User Manual
41
Note: When a signal
recording is waiting for the level trigger the “level”
icon appears
alternatively with the grey „signal” icon.
/
Gradient trigger
The Gradient + trigger starts a signal recording for Rec. Time under the
condition: the value of the Leq result ( Source ) averaged by 0.5 ms is greater than
the threshold value ( Level ) the speed of this Source result changing (gradient) is
greater than the gradient threshold ( Gradient
). In other cases, recording doesn’t
start, but if it has been already started it can be continued until the Rec. Time has
elapsed. The instrument checks the trigger condition also during the recording
and if the condition is met the recording will continue for another
Rec. Time .
Integration period trigger
When the Integr. Per trigger is selected, a signal recording is triggered every time
the measurement starts, and recording will last minimum Rec. Time . If the trigger
condition appears during recording (when Integration Period is shorter than
Rec. Time ), from this moment, the recording will continue for the next Rec. Time
and so on.
Manual trigger
When the Trig.manual trigger is selected, the signal
recording starts and ends after pressing simultaneously
the
◄
and
►
keys during the measurement. After
pressing these keys, the screen with the corresponding
message appears. The registration always stops after
period defined by the
Rec
. Time
parameter.
Note: When a signal recording is waiting for the gradient trigger manual
trigger or “integration period” trigger, the flashing “trigger” icon
superimposes on the grey „signal” icon.
The Filter position enables the user to choose the broadband frequency filter
during a wave recording: Z , A , C , B or LF .
The Sampling parameter defines the sampling frequency of wave recording:
24 kHz or 12 kHz .
The Signal Gain position enables the user to choose the gain of the recorded
signal: 0 dB
…
40 dB .
.
The Source position indicates the trigger source. Only one measured result can
be used as a triggering source in all modes, namely the instantaneous LEQ from
the first profile (with appropriate filter and detector), which is denoted here as
Leq(1) .
The threshold ( Level ) can be set in the range from 24 dB to 136 dB. The Source
value compares with the Level value every 0.5 milliseconds.
Checking triggering condition
The Tr. Period parameter defines the time interval for
checking the triggering condition as: Logger Step , 0.5ms ,
100ms and 1s .
►