MTS Multipurpose Elite - Manual (Page 405)

Description Callout
Valley B
Tolerance Bands C
Detector Triggers D
Enable after
You can use the Enable after command to specify how many feedback cycles occur before the activity
begins to monitor the selected signal. This allows the signal to stabilize before it is monitored.
If you select a channel for the Channel Reference, the activity begins counting cycles after the tapering is
complete.
For example, if you specify 6 cycles, and the waveform begins with a taper that includes 2 cycles, the
activity begins monitoring peaks and valleys on cycle 9.
If you do not use Channel Reference, the activity begins counting cycles immediately after the number of
cycles you specify. For instance, if you specify 6 cycles, and the waveform begins with a taper that includes
2 cycles, the activity begins monitoring for peaks and valleys on cycle 7.
In either case, if you click Stop and then Run on the Control panel, the activity restarts the count.
Reference values
If you do not select Default Reference Values, the first peak and valley detected by the activity become
the reference levels for the tolerance band.
Note:
The activity does not generate a trigger signal based on the first peak or valley.
If you select User-Defined Reference, you enter the upper and lower level values for the tolerance band.
This is a useful feature if it is possible that the first peak and valley used to establish the reference values
could be unusually large or otherwise irregular. With User-Defined Reference values, the controller uses
your preset reference values and compares them with the very first peak or valley at the start of the activity.
Note:
The Peak-Valley Change Detector activity triggers only the first time.
For More Information
Task
Reference
Peak-Valley Change Detector Activity Example (p. 405)
Peak-Valley Change Detector Activity Properties (p. 407)
Peak-Valley Change Detector Activity Example
Suppose you want to acquire a cycle of data each time the peaks or valleys of an input signal change by
a specified amount. Further, suppose you define a Peak-Valley Change Detector activity with the following
parameters:
MTS TestSuite | 405
Test Activities