Hello all , We are switching over from Totalchrome software to OpenlabCDS. I need guidance around custom calculation & report generation using Openlab . Could anybody help me please ? Thanks a lot

Our current total chrome software calculates the weight of the compound using following formula .

Wt of component = (areacounts/total areacounts )*(1/(1/RF)) where RF is response factor. This weight is then normalized to obtain normalized wt% by using formula (calcwt/total wt )*100

The wt% thus obtained is corrected for air interference using following formula: N2-4(O2)= corrected N2.

The data is then re normalized to 100% = This is corrected wt%

Corrected Wt % is used to calculate moles using molecular wt of the components. calculated moles= corrected wt%/MW

These calculated moles are used to calculate mol%= (calcmol/total mol) *100

Our current final report contains component Id , wt%, Corrected wt % & mol % . I am looking to generate a similar report

  • Hi 

    In OpenLab, have a look at he Help and Learning section on Calibration in OpenLab.  There are a couple of options in the Calibration>General tab of your OpenLab Processing method.

    Wt of component is easy, assuming that you have a calibration that calculates the response factor, or you manually enter the response factor in the calibration table of the Processing method.

    Then it becomes more challenging... I think you have no option other than to head to the custom calculations because of this line:

    N2-4(O2)= corrected N2

    I'm not familiar with the analysis that you are doing, so I can't really give you more detail than this. Maybe providing more details about all of the analytes you're trying to measure might help.

    I'm not sure that you'll get the full answer here on the community forum, but may have to look for some training/consultancy to help you build and test the calculations.


  • Thanks Andy for responding . This is analysis of gases using GC-TCD . Most of the response factors used are obtained from Dietz factors except that for H2 . Could you / anyone guide  me with the custom calculator ?

  • Hi 

    For custom calculations, you could start with the OpenLab Help and Learning "How to" guides.

    If you want to do all of this in custom calculations, you will need calculations like these to start with

    A variable named TotalArea with scope Injection using the formula


    I will add more to this thread, when I have time later today!


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