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Calculates the DC and/or the RMS values of an input waveform or array of waveforms. The data type you wire to the signal in input determines the polymorphic instance to use. Details  Example

Use the pull-down menu to select an instance of this VI.

Select an instanceAveraged DC-RMS for 1 ChanAveraged DC-RMS for N Chan

Averaged DC-RMS for 1 Chan

	reset resets the history of your time signal. You typically use reset to reset the exponentially averaged measurement.
	signal in is the input waveform.
	averaging type is the type of averaging used during the measurement. In this single-point-per-block VI, the integration time is selected automatically by your input record length. 0 Linear—Integration time is equal to the record length. 1 Exponential—Time constant is half the record length.
	averaging time defines dt of DC value waveform and RMS value waveform in seconds. The default is –1.00, corresponding to average time = input block duration. For linear averaging, each output data point results from performing the averaging process for the time period specified by averaging time. For exponential averaging, each output data point results from exponential integration performed for the time period specified by averaging time using exp. time constant.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	averaging control contains the advanced parameters used to completely control the DC or RMS measurement. window for DC is the window to be applied to the time record before DC computation. 0 Rectangular (no window) 1 Hanning 2 Low side lobe output function selects the type of measurements to be performed. If you need only DC or RMS measurements, selecting these components separately increases the processing speed. 0 DC only 1 RMS only 2 DC and RMS window for RMS is the window to be applied to the time record before RMS computation. 0 Rectangular, (no window) 1 Hanning 2 Low side lobe exp. time constant specifies the time constant (RC) of your DC or RMS measurement. exp. time constant = –1.00 corresponds to a value of input block duration/2. Set Ignore input time stamp to TRUE when you do not want the VI to check for continuity using t0 values.
	data ready indicates the DC value waveform and RMS value waveform contain data. A value of FALSE means that the waveforms do not contain data.
	DC value waveform indicates DC values of signal in computed over averaging time seconds and time stamped continuously from the last reset.
	RMS value waveform indicates RMS values of signal in computed over averaging time seconds and time stamped continuously from the last reset.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.
	measurement info returns information about your measurement, mainly warnings for inconsistencies in your input signal. uncertainty is reserved for future use. Warning is TRUE if a warning is generated during processing. comments contains a warning message when Warning is true.

Averaged DC-RMS for N Chan

It is assumed that the array of input waveforms is the result of a multichannel acquisition where each element in the array of waveforms is a distinct and separate channel of data.

	reset resets the history of your time signal. You typically use reset to reset the exponentially averaged measurement.
	signals in is the array of input waveforms.
	averaging type is the type of averaging used during the measurement. In this single-point-per-block VI, the integration time is selected automatically by your input record length. 0 Linear—Integration time is equal to the record length. 1 Exponential—Time constant is half the record length.
	averaging time defines dt of DC value waveform and RMS value waveform in seconds. The default is –1.00, corresponding to average time = input block duration. For linear averaging, each output data point results from performing the averaging process for the time period specified by averaging time. For exponential averaging, each output data point results from exponential integration performed for the time period specified by averaging time using exp. time constant.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	averaging control contains the advanced parameters used to completely control the DC or RMS measurement. window for DC is the window to be applied to the time record before DC computation. 0 Rectangular (no window) 1 Hanning 2 Low side lobe output function selects the type of measurements to be performed. If you need only DC or RMS measurements, selecting these components separately increases the processing speed. 0 DC only 1 RMS only 2 DC and RMS window for RMS is the window to be applied to the time record before RMS computation. 0 Rectangular, (no window) 1 Hanning 2 Low side lobe exp. time constant specifies the time constant (RC) of your DC or RMS measurement. exp. time constant = –1.00 corresponds to a value of input block duration/2. Set Ignore input time stamp to TRUE when you do not want the VI to check for continuity using t0 values.
	data ready indicates the DC value waveform and RMS value waveform contain data. A value of FALSE means that the waveforms do not contain data.
	DC value waveforms is an array of waveforms containing DC values.
	RMS value waveforms is an array of waveforms containing RMS values.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.
	measurements info is an array that returns information about your measurement, mainly warnings for inconsistencies in your input signal. uncertainty is reserved for future use. Warning is TRUE if a warning is generated during processing. comments contains a warning message when Warning is true.

Averaged DC-RMS Details

This VI gives more precise control over the individual calculations (DC and/or RMS) than the Basic Averaged DC-RMS VI.

This VI is designed to process a single channel or multiple channels continuously, typically from within a For Loop or a While Loop.

Note  The Averaged DC-RMS VI assumes that consecutive data blocks are continuous. If they are not, the VI returns a warning in measurement info, unless Ignore input time stamp is enabled.

Example

Refer to the Advanced DC-RMS Measurement VI in the labview\examples\measure\maxmpl.llb for an example of using the Averaged DC-RMS VI.