Skip to main content

Tanks with Zero Measurement or Tolerance

This analysis rule includes the list of tank elements that have a mass or volume measuring zero or have a zero value for the measurement tolerance.

Due to the tank geometry, a tank typically has a non-zero inventory even when considered empty. A value of zero for the mass or volume can indicate the following:

  • An invalid gauge to volume calculation.

  • An invalid volume to mass calculation.

  • Missing data.

  • Invalid tank configuration.

    A zero tolerance value is also atypical since it allows no error to be placed on that value in the balancing calculations, such as the mass balance. A value of zero for the mass or volume tolerance can indicate the following:

  • An invalid mass/volume tolerance Attribute value.

  • A missed or invalid tolerance Attribute configuration.

The following table lists a sample log output for this analysis.

Sample Log

TimeSeverityElementAttributeMessage
7/25/2005 13:22...REPORTING TANKS WITH ZERO MEASUREMENT/TOLERANCE - BASIS= VOLUME
7/25/2005 13:22ErrorTankATolerance Attribute VolumeTolerance has a value of 0(L)
7/25/2005 13:22ErrorTankBMeasurement Attribute NetVolume has a value of 0(L) , Tolerance Attribute VolumeTolerance has a value of 0(L)

Analysis Method​

  1. Collect a list of all tank elements in the current Case that satisfy the following criteria:
  • Status Attribute value is IS (In Service).
  1. Based on the analysis basis selection, mass or volume, check if the measurement is zero. If the manual adjustment value is True, then use a corrected value for the comparison.
  2. Based on the analysis basis selection, mass or volume, check if the measurement tolerance is zero. If the manual adjustment value is True, then use a corrected value tolerance for the comparison.
  3. Write to the log section of the case. Report the violating tank information.

Configuration Using the Wizard​

The configuration of the Tanks with Zero Measurement or Tolerance is a selection of the General Gross Error Analysis Rule. You open the window for configuring the test (shown in the following figure) from the General Gross Error Analysis Rule Wizard.

  1. Open the Gross Error Configuration window as described in Configuring - General Gross Error Analysis Rule.

  2. On the Tanks tab, select Tanks with zero measurement or tolerance.

    A Tanks with zero measurement or tolerance - Attributes window opens.Figure 382: Tanks with zero measurement or tolerance - Attributes window

  3. Select measurement basis and Attributes according to the following table:

    Attributes

    SelectionsDescription
    Measurement BasisSelect either mass or volume basis.
    MeasuredTank inventory actual measurement. The default is 'MeasuredMass' or 'NetVolume' depending on mass or volume selection.
    CorrectedTank inventory corrected measurement. The default is 'CorrectedMass' or 'CorrectedVolume' depending on mass or volume selection.
    Manual FlagFlag to indicate if a corrected measurement was used for the tank inventory. The default is to 'ManualAdjustmentFlag'.
    ToleranceTank measured value tolerance. The default is to 'MassTolerance' or 'VolumeTolerance' depending on mass or volume selection.
    Corrected ToleranceTank corrected value tolerance. The default is to 'CorrectedMassTolerance' or 'CorrectedVolumeTolerance' depending on mass or volume selection.
    StatusTank in/out of service status. The default is to 'ObjectStatus'.

  4. Click OK to finish the configuration.

    The text "CONFIGURED" displays next to the 'Tanks with zero measurement or tolerance' selection.

  5. To run this test, see Running the General Gross Error Analysis.