Run Stopper - HBM SomatXR CX23-R User Manual

Application Note: Stopping a test after a defined time period
To stop a test run after a defined time period:
1. Add a Time channel
2. Add a Signal calculator
test run duration.
3. Add a Run stopper channel with the Signal calculator channel as the input channel.
CX23-R and EX23-R
NOTE
The pulse counter frequency output is also updated if the time period since the
last set of edges exceeds the current output. This results in improved results as
the pulse train slows or stops.
Output rate factor: Specify the down sample factor that determines the output
channel sample rate. For example, for an input channel with a sample rate of
10000 S/s and an Output rate factor of 1000, the output channel sample rate is 10
S/s. The value must be an integer of 10 or greater.
Output scale factor: Specify the scale factor to convert the output data from Hz
to the desired physical units. The Output scale factor cannot be zero.
Minimum output frequency: Specify the minimum frequency, f , of the output
channel between 0.001 and 1.0 Hz. If a new pulse is not detected within the period
of 1/ f , the output value is set to f . The value remains at f until the detected pulse
period is less than 1/ f . For example, if the minimum output frequency is 0.1 Hz
and the input channel is a 50 Hz pulse train that suddenly stops, the pulse counter
output remains at 50 Hz until a new pulse frequency is detected or until 10
seconds (1/ f ) have elapsed; at that point, the output value is set to 0.1 Hz. This
minimum output frequency is also the initial output value until the first pulse is
detected.
NOTE
The accuracy of the pulse frequency measurements depends on only the sample
rate of the input channel. For example, using an input channel sampled at 2000
S/s provides 1% accuracy of a 20-Hz pulse signal and 0.1% of a 2-Hz pulse
signal. As a general rule, the input sample rate should be 100 times the maximum
expected pulse frequency to provide 1% or better accuracy of the entire pulse
frequency range.
4.4.12 Run stopper
The Run stopper channel stops a test run when the logical input channel becomes
TRUE.
NOTE
Because the input channel is processed in frames that can be buffered, the test
run does not stop immediately but typically stops within a fraction of a second
after the input channel becomes TRUE. In the worst case, assume that several
seconds could elapse before the test run stops.
with the name elapsed_time.
channel with the expression elapsed_time >= 600, where 600 seconds is the desired
a4275-8.0 en HBM: public
4 Setting up and running a test
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