Polarimeter
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      3. Polarimeter

      Dark Sample Error

      Basic troubleshooting and maintenance steps for instruments displaying a Dark Sample error for cleaning the splash glasses and sample cell.

      A Dark Sample error is commonly caused by a lamp that has failed. As a first step, confirm that the instrument lamp is on by placing your hand in the trough. The lamp is located on the left side of the instrument.

      If the lamp is not on and you have a new lamp to replace it with, please follow the Lamp Replacement Instructions below. If you do not have a replacement lamp, please request a quote for a lamp.

      If the lamp is on, please confirm that the splash glasses and sample cell end glasses are clean and that there are no bubbles in the sample cell. I've attached the sample cell reassembly instructions for reference to ensure reassembly is done properly, see page 2.
       
      Lamp Replacement Instructions
      1. Remove the small instrument cover located on the left side of the instrument.
      2. Loosen the thumb screw that holds the lamp in place. Remove the lamp by holding the sides of the connector and slide the lamp out of the instrument.
      3. To remove the lamp, gently pull down on the wires to release the legs that hold the lamp in the connector and remove the lamp.
      4. Install the new lamp in the connector by gently pulling down on the wires while you insert the legs of the lamp into the holes on the connector. Clean the lamp with a soft cloth and alcohol before installing the lamp into the Polarimeter. Tighten the thumb screw gently to hold the lamp in place.
      5. Reinstall the cover.

       

      Splash Glass Cleaning

      1. Insert your finger in the splash glass and gently pull out the splash glass on each end of the trough.
      2. Disassemble the splash glass by unscrewing the silver ring on the backside of the splash glass.
         
      3. Clean the glass with cleaner (Windex works well) and dust free cloth. 
      4. Reassemble the splash glass assembly, do not overtighten the assembly.
      5. Insert the splash assemblies back into the trough. 

       

      Sample Cell Cleaning & Reassembly

      Simplified Cleaning Procedure

      1. Flush cell with solvent i.e. Acetone, Alcohol, DSMO or similar solvent through inlet or outlet port.
      2. Dry with compressed air (nitrogen) through inlet or outlet port

      Advanced Cleaning Procedure

      Note: This cleaning method is only necessary when the simplified cleaning procedure still results in residue left by the solute. The frequency of this level of cleaning will be determined by each customer's unique application.

      1.  Remove the 4 screws at the ends of the tube using an allen wrench provided.
      2. Disassemble the cell ends
      3. Clean "wetted" pieces with Acetone, Alcohol, DSMO or similar solvent. Dry with lint free paper.
      4. Reassemble the cell ends and tighten the screws with the allen wrench provided. 
        Note: Be sure to install the glass first followed by the rubber seal, then the end cap as shown below.