Jump to main content

# Harmonic Analysis Command

When the Demo Meter application receives an `HRR[n]` command, it configures the metrology library to enable the harmonics computation and to calculate the data corresponding to the harmonic number n. Then, the metrology driver receives the data from the library and computes the rms currents and voltages of the selected harmonic, and sends the data back to Demo Meter application.

The following example computes the values for the 3rd harmonic.

    HRR[3]
    The calculated harmonic Irms/Vrms:
    Vrms_Har_CH00(V)    Vrms_Har_CH01(V)    Vrms_Har_CH02(V)    Irms_Har_CH03(A)
    0.235               0.185               0.203               0.001
    Irms_Har_CH04(A)    Irms_Har_CH05(A)    Irms_Har_CH06(A)    Irms_Har_CH07(A)
    0.001               0.001               0.000               0.000

There is an extended version of this command, the HRRX command, which allows 2 new functionalities:

- Start the analysis and computation of RMS values, and keep updating it on every integration period, until a new HRRX command with a specific parameter is received
- Perform the analysis and computation for one harmonic order

The following example shows the command to Start analysis (parameter ‘1’) for harmonic 3rd.

    HRRX[1][3]The calculated harmonic Irms/Vrms:
    Vrms_Har_CH00(V)    Vrms_Har_CH01(V)    Vrms_Har_CH02(V)    Irms_Har_CH03(A)
    0.235               0.195               0.210               0.001
    Irms_Har_CH04(A)    Irms_Har_CH05(A)    Irms_Har_CH06(A)    Irms_Har_CH07(A)
    0.001               0.001               0.000               0.000

To stop the harmonic analysis, the command HRRX is sent with parameter ‘0’ (Stop). The last computed values are printed again on the Console.

    HRRX[0][3]The calculated harmonic Irms/Vrms:
    Vrms_Har_CH00(V)    Vrms_Har_CH01(V)    Vrms_Har_CH02(V)    Irms_Har_CH03(A)
    0.244               0.209               0.224               0.001
    Irms_Har_CH04(A)    Irms_Har_CH05(A)    Irms_Har_CH06(A)    Irms_Har_CH07(A)
    0.001               0.001               0.000               0.000

Note: Between the HRRX[1][X] printed output, and the HRRX[0] one, nothing is printed to the Console, all calculations are made by the Driver and sent to application, but no prints are made, to avoid overloads. User may decide to add code to handle every calculation in their own way. In the meantime, the Console can be used for different commands, it is not blocked.

Rev: E