Before you can use FieldLab Desktop to administer Engineering Units, you must first Add the FieldLab to FieldLab Desktop. Full instructions for doing so are here: Add a FieldLab to FieldLab Desktop
Select the FieldLab from the FieldLabs screen.
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Go to the Settings Tab and select the Change button in the Engineering Units box.
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Select the Engineering Unit you'd like to Add or Remove from the gauge.
In the pictured example, the engineering unit "bar" is selected to be added to the FieldLab.
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Move the highlighted Engineering Unit to the queue by clicking the 'Add to FieldLab' button. Save your changes by clicking the 'Save Changes' Button.
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