Amplitude and Levels Express VI

LabView Acquire Signals Express VIs

Amplitude and Levels Express VI

Owning Palette: Time-Domain Measurements Express VIs

Installed With: LabVIEW SignalExpress

Measures DC, RMS, positive and negative peak, and peak-to-peak values of a signal.

You can measure DC and RMS values with linear or exponential averaging. If you select Linear, you can apply a window to the signal.

You also can individually export the different measurement results.

Dialog Box Options
Block Diagram Inputs
 Place on the block diagram  Find on the Functions palette

Dialog Box Options

ParameterDescription
Input SignalDisplays the input signal.
  • Displayed signal—Specifies the signal(s) to display in the preview graph(s). This option appears only when you select a group of signals for the input.
    Note  If the input signals include scalar values that depend on the values of input waveform signals, you cannot specify to display all signals in the preview graph(s).
Autoscale amplitudeAutoscales the preview graph along the y-axis. The default is to autoscale the amplitude.
Input/OutputContains the following options:
  • Input signal—Specifies the input signal to be measured.
  • Export DC value—Exports the DC value to the Project View.
  • Export RMS value—Exports the RMS value to the Project View.
  • Export +Peak value—Exports the positive peak value to the Project View.
  • Export -Peak value—Exports the negative peak value to the Project View.
  • Export Peak-Peak value—Exports the difference between the positive and negative peak values to the Project View.
ConfigurationContains the following options:
  • DC-RMS Setup—Contains the following options:
    • Averaging type—Sets the type of averaging to linear or exponential. The default is Linear.
    • Window—Sets the type of window when you use linear averaging. Windowing can sometimes help increase measurement accuracy for signals that are dominated by periodic components

      Window is not available if you select Exponential as the averaging type. Window contains the following options: Rectangular (none), Hanning, and Low side lobe. The default is Rectangular (none).
  • Peak Setup—Contains the following option:
    • Hold peaks—Specifies to hold the peak levels until you click the Reset Amplitude and Levels button or the Reset All button or restart your measurement. The default is to not hold the peak levels.
  • DC-RMS Results—Contains the following options:
    • DC value—Returns the measured DC value.
    • RMS value—Returns the measured RMS value.
  • Peak Results—Contains the following options:
    • +Peak value—Returns the positive peak value of the input signal.
    • -Peak value—Returns the negative peak value of the input signal.
    • Peak-peak value—Returns the difference between the positive and negative peak values of the input signal.

Block Diagram Inputs

ParameterDescription
Input SignalDisplays the input signal.
  • Displayed signal—Specifies the signal(s) to display in the preview graph(s). This option appears only when you select a group of signals for the input.
    Note  If the input signals include scalar values that depend on the values of input waveform signals, you cannot specify to display all signals in the preview graph(s).