Last Modified: June 25, 2019

Performs a full harmonic analysis, including measuring the fundamental frequency tone and harmonics, and returning the fundamental frequency, all harmonic amplitude levels, and the total harmonic distortion (THD).

Source of the signal and spectrum to export.

Name | Description |
---|---|

none | Uses the fastest computation. |

input signal | Exports the input signal only. |

fundamental signal | Exports the single sine tone. |

residual signal | Exports the signal minus tone. |

harmonics only | Exports detected harmonics only. |

noise and spurs | Exports the signal minus tone and harmonics. |

**Default: **none

Center frequency to use in the frequency-domain search for the fundamental tone frequency.

**Default: **-1

Frequency width, as a percentage of the sampling rate, for the frequency-domain search for the fundamental tone frequency.

**Default: **5

Highest harmonic, including the fundamental tone, used for the harmonic analysis. For example, for 3rd harmonic analysis, this control should be set to 3 to measure the fundamental, second, and third harmonic.

**Default: **19

Error conditions that occur before this node runs.

The node responds to this input according to standard error behavior.

Standard Error Behavior

Many nodes provide an **error in** input and an **error out** output so that the node can respond to and communicate errors that occur while code is running. The value of **error in** specifies whether an error occurred before the node runs. Most nodes respond to values of **error in** in a standard, predictable way.

**Default: **No error

A Boolean specifying whether to include only frequencies less than the Nyquist frequency, or half the sampling rate, in the harmonic search.

True | Includes only frequencies less than the Nyquist frequency. |

False | Searches the frequency domain beyond the Nyquist frequency by assuming that these higher frequency components have aliased. |

**Default: **True

Spectrum of the exported signal.

This output can return a cluster or a 1D array of clusters.

Start frequency, in Hz, of the spectrum.

Frequency resolution, in Hz, of the spectrum.

Computed spectrum.

Waveform of the exported signal.

This output can return a waveform or a 1D array of waveforms.

Detected fundamental frequency resulting from searching the frequency domain.

This output can return a double-precision, floating-point number or a 1D array of double-precision, floating-point numbers.

Use the center frequency and frequency width to set the frequency domain search range. All harmonics are measured at integer multiples of this fundamental frequency.

Measured total harmonic distortion up to and including the highest harmonic.

This output can return a double-precision, floating-point number or a 1D array of double-precision, floating-point numbers.

This output is defined as the ratio of the RMS sum of the harmonics to the amplitude of the fundamental tone. To compute THD as a percentage, you must multiply it by 100.

Array of amplitudes of the measured harmonics in volts if the input signal in is in volts.

This output can return a 1D array of double-precision, floating-point numbers or a 1D array of clusters.

The array index is the harmonic number including 0 (DC), 1 (fundamental), 2 (second harmonic),... *n* (*n*^{th} harmonic), up to and including the highest harmonic.

Error information.

The node produces this output according to standard error behavior.

Standard Error Behavior

**error in** input and an **error out** output so that the node can respond to and communicate errors that occur while code is running. The value of **error in** specifies whether an error occurred before the node runs. Most nodes respond to values of **error in** in a standard, predictable way.

**Where This Node Can Run: **

Desktop OS: Windows

FPGA: Not supported

Web Server: Not supported in VIs that run in a web application