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Owning Palette: Tachometer Processing VIs

Installed With: Sound and Vibration Measurement Suite

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

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

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

OAT Digital 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.
	digital tacho info specifies the tachometer information from the digital input channel of the counter device. tacho counts specifies the counter value at each tachometer pulse. The default is 0. counter timebase [Hz] specifies the frequency of the counter clock in hertz. The default is 1,000. counter task type specifies how this VI measures tachometer pulses. 0 period measurement—Specifies tacho counts as the count between two sequential pulses. 1 event counting—(Default) Specifies tacho counts as the count from the measurement start time to the pulse arrival time. counter digit specifies the number of digits the counter generates. The default is 32.
	pulse/revolution specifies the number of pulses the tachometer generates during each revolution. The default is 1.
	signal duration [s] specifies the duration of the sound or vibration signal, in seconds, synchronized with the input tachometer signal.
	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.
	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.
	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? returns TRUE if no tachometer pulses exist in the input signal. This VI returns FALSE if tachometer pulses exist in the input 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 Digital 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.
	digital tacho info specifies the tachometer information from the digital input channel of the counter device for each channel. tacho counts specifies the counter value at each tachometer pulse. The default is 0. counter timebase [Hz] specifies the frequency of the counter clock in hertz. The default is 1,000. counter task type specifies how this VI measures tachometer pulses. 0 period measurement—Specifies tacho counts as the count between two sequential pulses. 1 event counting—(Default) Specifies tacho counts as the count from the measurement start time to the pulse arrival time. counter digit specifies the number of digits the counter generates. The default is 32.
	pulse/revolution specifies the number of pulses per revolution the tachometer generates for each channel. The default is 1.
	signal duration [s] specifies the duration of the sound or vibration signal, in seconds, synchronized with the input tachometer signal for each channel.
	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.
	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.
	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? returns TRUE when no tachometer pulses exist in the input signal for each channel. This VI returns FALSE if tachometer pulses exist in the input 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.