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      1. Ask Professor Rudy
      2. How To
      3. AlcoTest

      How to create an offset and new method, Validate the system, and test a sample on an Alcotest

      Below are the steps for creating an offset, validation of the system, and testing a sample on an Alcotest.

      Validation of System (Basic Test each Day)

      1. Clean Prism and U-tube

        1. Refractometer: Clean prism three times with ethanol, dry with towel

        2. Density meter: Flush U-tube with ethanol, dry

      2. Validate

        1. Refractometer: Place distilled water on prism, and enter refractometer software. Accessories->refractometer

          1. Check that value is 1.3330, if not zero system to distilled water.

        2. Density: Inject distilled water into U-tube

          1. Menu 123->Calibration 519->Calibration Verification->Water at 20C.

      If this fails recalibration system see manual calibration adjustment. 

      Testing a Sample

      1. Clean: Clean Prism on refractometer and U-tube on density meter using same cleaning procedures as above.

      2. Place product on prism and inside U-Tube. Pg. 63 Manual.

        1. Make sure no bubbles are in U-Tube! Use pressure if necessary.

      3. Select Method, and then select the Proper Method/Product from the list. Select Start.

      Creating a New Product/Method and Applying Offset from Distillation for Obscured Products

      STEP 1. VALIDATE AND CLEAN

      1. Validate system as described in SOP
      2. Clean density meter and refractometer

      STEP 2. DETERMINE OFFSET

      1. Choose Rudolph factory default method AlcoTestABV AOAC.

      2. Load sample in density meter and refractometer

      3. Confirm no bubbles in U-Tube

      4. Measure and write down the value from AlcoholABV AOAC in Line 1 Measured Result.

      5. Obtain a reference result by another method and confirm the units of that result (US Proof, AOAC ABV, UK Proof, OIML ABV). Write value down in Reference Result Line 2 above

      STEP 3. CREATE CUSTOM PARAMETER pg 60 manual

      1. Menu->Operational Parameters->Instrument Configuration->Concentrations->Custom Parameter->Add
      2. Choose a name for your new Parameter/Product e.g. Captain Morgan Percent Alcohol Corrected.
      3. Input Current Reading from Measured Result from line 1 above.
      4. Input Reference Reading from Reference Result line 2 above
      5. Select Group=Polynomial & Parameters=AlcoholABV AOAC

      STEP 4. CREATE CUSTOM METHOD pg 39 manual

      1. Menu->Method Management->Add/Copy->Copy from an Existing Method
      2. Select AlcoTest ABV AOAC. Select continue
      3. Rename Copy AlcoTest ABV AOAC method to Product Name e.g. Captain Morgan
      4. Edit this new Method/Product.
        1. Display Parameters.
        2. Under Group select Custom, this is where offset parameters are stored.
        3. Select your new offset parameter that you created from Step 3. ( e.g. Captain Morgan Percent Alcohol Corrected)
        4. Add this to the last parameter on the list with arrows.
        5. Save and exit, load your new method and test