Stanford Research Systems SR780, Руководство по эксплуатации и программированию

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Limit Testing 1-59
Limit Testing
This example is intended to familiarize the user with limit testing. Limit Testing tests the measurement
data against a set of defined Limit Segments. When measurement data exceeds a Limit Segment at any
point, the test fails. Each display has its own set of Limit Segments.
A Limit Segment is defined as the line between the pair of points (X0,Y0) and (X1,Y1). The segment
values between the endpoints are calculated for the displayed span. A segment may be defined as either
an Upper or Lower limit. Measurement data which is greater than an Upper limit or less than a Lower
limit cause the test to fail.
1. Press [System]
Display the System menu.
Press <Preset> Preset returns the unit to its default settings.
Press [Enter] to confirm Preset.
Preset requires confirmation to prevent accidental
reset. Wait until the self tests are completed.
2. Connect the Source Output to the Channel 1 A
Input.
Setup to analyze the source output. The default
source is a 10.24 kHz sine.
Press [Auto Scale A]
Scale the display to show all of the data.
3. Press [Analysis]
Select the Analysis menu.
Press <Limit Test>
Choose Limit Test.
Press <Edit Limits>
Show the Edit Limits menu. We can’t turn on any
testing until limits are defined.
Press <New Segment>
This function adds a new segment. The new
segment has a default position and length.
The segment is defined by its endpoints, (X0,Y0)
and (X1,Y1). These values are specified for the
current view and units, in this case, Hz for the x
values and dBVpk for the y values.
The segments are drawn in half intensity. The arrow
markers at the end points point down for upper
limits and point up for lower limits. The current
segment (whose endpoints are shown and edited in
the menu) has two additional arrows at the
endpoints.
Press <X0> Select X0 first.
Press [8] [0] [0] [0] [Enter]
Enter a value of 8000 Hz.