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Owning Palette: Tachometer Processing VIs

Installed With: Sound and Vibration Measurement Suite

Locates tachometer pulse positions in analog tachometer signals and calculates the rotational speed of the device. The data type you wire to the analog tacho signal input determines the polymorphic instance to use.

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

Select an instance OAT Analog Tacho Process (1 Tacho)OAT Analog Tacho Process (N Tachos)

OAT Analog Tacho Process (1 Tacho)

	reset? specifies the initialization of the internal states. The first time this VI runs, or when reset? is TRUE, the internal states initialize to zero. If reset? is FALSE, this VI sets the internal states to the final states from the previous call to the VI. The default is FALSE.
	missing pulses? specifies if pulses are missing in analog tacho signal. If missing pulses? is TRUE, this VI finds and interpolates the missing pulses. The default is FALSE.
	analog tacho signal specifies the input analog tachometer signal.
	threshold specifies the trigger level that a tachometer pulse must cross to be considered valid. The default is Inf. When threshold is Inf, this VI sets the threshold level automatically.
	pulse/revolution specifies the number of pulses the tachometer generates during each revolution. The default is 1.
	hysteresis specifies a level above or below the threshold level. Use hysteresis to reduce false triggering that noise in an analog tachometer signal might cause. When the slope is Rising, the analog tachometer signal must fall below threshold minus hysteresis before this VI detects the next pulse. When the slope is Falling, the analog tachometer signal must rise above threshold plus hysteresis before this VI detects the next pulse. The default is 0.
	error in describes error conditions that occur before this node runs. The default is no error. If an error occurred before this node runs, the node passes the error in value to error out. This node runs normally only if no error occurred before this node runs. If an error occurs while this node 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 node ran or FALSE (checkmark) to indicate a warning or that no error occurred before this node 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 node that produced the error or warning. The default is an empty string.
	pulse width specifies the minimum number of points a valid tachometer pulse must contain. pulse width must be greater than zero. The default is 2.
	slope specifies the type of edge that indicates the arrival of a tachometer pulse. 0 Rising—(Default) Specifies that a rising edge indicates the arrival of a tachometer pulse. 1 Falling—Specifies that a falling edge indicates the arrival of a tachometer pulse.
	speed profile returns information about the tachometer pulse arrival time and the rotational speed at each pulse. time [s] returns the arrival time, in seconds, of each tachometer pulse. speed [RPM] returns the rotational speed, in revolutions per minute, of each tachometer pulse.
	actual threshold returns the threshold that this VI uses.
	speed position info returns the position information of the speed [RPM] subparameter. positions [s] returns the locations of the samples, in seconds. samples/rev returns the number of samples in each revolution.
	no tacho? indicates whether tachometer pulses exist in analog tacho signal.
	error out contains error information. If error in indicates that an error occurred before this node ran, error out contains the same error information. Otherwise, it describes the error status that this node 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 node that produced the error or warning.

OAT Analog Tacho Process (N Tachos)

	reset? specifies the initialization of the internal states. The first time this VI runs, or when reset? is TRUE, the internal states initialize to zero. If reset? is FALSE, this VI sets the internal states to the final states from the previous call to the VI. The default is FALSE.
	missing pulses? specifies if pulses are missing in analog tacho signals for each channel. If missing pulses? is TRUE, the VI finds and interpolates the missing pulses. The default is FALSE.
	analog tacho signals specifies the input analog tachometer signal for each channel.
	threshold specifies, for each channel, the trigger level that a valid tachometer pulse must cross to be considered valid. The default is Inf. When threshold is Inf, this VI sets the threshold automatically.
	pulse/revolution specifies, for each channel, the number of pulses the tachometer generates during each revolution. The default is 1.
	hysteresis specifies, for each channel, a level above or below the threshold level. Use hysteresis to reduce false triggering that noise in an analog tachometer signal might cause. When the slope is Rising, the analog tachometer signal must fall below threshold minus hysteresis before this VI detects the next pulse. When the slope is Falling, the analog tachometer signal must rise above threshold plus hysteresis before this VI detects the next pulse. The default is 0.
	error in describes error conditions that occur before this node runs. The default is no error. If an error occurred before this node runs, the node passes the error in value to error out. This node runs normally only if no error occurred before this node runs. If an error occurs while this node 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 node ran or FALSE (checkmark) to indicate a warning or that no error occurred before this node 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 node that produced the error or warning. The default is an empty string.
	pulse width specifies, for each channel, the minimum number of points a valid tachometer pulse must contain. pulse width must be greater than zero. The default is 2.
	slope specifies, for each channel, the type of edge that indicates the arrival of a tachometer pulse. 0 Rising—(Default) Specifies that a rising edge indicates the arrival of a tachometer pulse. 1 Falling—Specifies that a falling edge indicates the arrival of a tachometer pulse.
	speed profiles returns information about the tachometer pulse arrival time and the rotational speed at each pulse for each channel. time [s] returns the arrival time, in seconds, of each tachometer pulse. speed [RPM] returns the rotational speed, in revolutions per minute, of each tachometer pulse.
	actual threshold returns the threshold that this VI uses for each channel.
	speed position info returns the position information of speed [RPM] for each tachometer signal. positions [s] returns the locations of the samples, in seconds. samples/rev returns the number of samples in each revolution.
	no tacho? indicates whether tachometer pulses exist in analog tacho signals for each channel.
	error out contains error information. If error in indicates that an error occurred before this node ran, error out contains the same error information. Otherwise, it describes the error status that this node 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 node that produced the error or warning.