Svantek SV 971A, Руководство пользователя

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SV 971A User Manual
43
Slope trigger
The Slope+ / Slope - trigger starts a signal recording under the condition: rising
value of the Leq result ( Source ) integrated by 0.5 ms passes above/below the
threshold level ( Level ).
After pressing the <Start> key the instrument checks the trigger condition with steps, defined by the
Tr. Period parameter, and if condition is met starts the signal recording. Recording lasts minimum
Rec. Time , and during this time the instrument continues to check the trigger condition with the
Tr. Period step. Provided that Tr. Period is shorter than Rec. Time , if next trigger condition is met during
Rec. Time the instrument triggers recording again, so it will continue from this moment by additional
Rec. Time and so on. If during next recording time there are no triggers, recording will be stopped after
the last trigger plus Rec. Time . Assuming, that after first recording trigger conditions continue to be
checked, new wave recording may start during the same measurement time.
The attached example shows that between
measurement start and stop two records
were created. The first record is equal to the
Rec. Time , because during this period no
second trigger condition has been met.
During
the second recording the
measurement was stopped, and the record
is shorter than
Rec. Time .
Note:
When a signal recording is waiting for the slope trigger the “slope”
icon superimposes on the grey „signal” icon.
/
Level trigger
The Level+ / Level
–
trigger starts a signal recording which will last the Rec. Time
under the condition: value of the Leq result ( Source ) integrated by 0.5 ms is
greater/lower than the threshold value ( Level
). In other cases, recording doesn’t
start, but if it has been already started it can be continued until the Rec. Time has
elapsed.
If during Rec. Time a trigger condition
appears, recording will be prolonged for
another
Rec. Time from the moment of that
trigger condition and so on.
Note:
When a signal recording is waiting for the level trigger the “level”
icon appears alternatively with the grey „signal” icon.
/
Gradient trigger
The G 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