Mask and Limit Testing
- Updated2025-07-30
- 5 minute(s) read
Performs limit testing on Signals.

Dialog Box Options
| Option | Description |
|---|---|
| Upper Limit | Contains the following options:
|
| Lower Limit | Contains the following options:
|
| Result Preview | Displays a preview of the measurement. The Result Preview plot indicates the value of the selected measurement with a dotted line.
If you wire data to the Express VI and run the VI, Result Preview displays real data. If you close and reopen the Express VI, Result Preview displays sample data until you run the VI again. If the cutoff frequency values are invalid, Result Preview does not display valid data. |
Inputs/Outputs
error in
—
Describes error conditions that occur before this node runs.
Signals
—
Contains the input signal or signals.
Lower Limit
—
Specifies the lower limit for mask and limit testing. The value you wire to this input overrides the value you set in the configuration dialog box.
Upper Constant
—
Compares Signals to the value in Upper Constant. The value you wire to this input overrides the value you set in the configuration dialog box.
Lower Constant
—
Compares Signals to the value in Lower Constant. The value you wire to this input overrides the value you set in the configuration dialog box.
Upper Limit
—
Specifies the upper limit for mask and limit testing. The value you wire to this input overrides the value you set in the configuration dialog box.
Point Evaluation
—
Returns the results of the limit testing at each data point. If Point Evaluation is TRUE, the data point is less than or equal to the upper limit and greater than or equal to the lower limit.
Tested Signals
—
Returns the upper and lower limits, the input signal, and the failures.
error out
—
Contains error information. This output provides standard error out functionality.
Passed
—
Indicates the result of limit testing. If Passed is TRUE, the signal is less than or equal to the upper limit and greater than or equal to the lower limit. |
The Express VI compares Signals with the upper and lower limits you set and returns the result of the comparison at each data point. The Express VI also returns an array of waveforms that contains the upper limit and lower limit, the signal, and the failures.
error in
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Signals
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Upper Constant
—
Point Evaluation
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error out
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Passed
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