Maintaining the Axial Pre-Optic Window

Answer

This Information Applies To: Agilent 5100, 5110, 5800, 5900 ICP-OES

Issue

The axial pre-optic window needs checking from time to time to ensure it is clean.

If the axial pre-optic window is dirty, it must be cleaned or replaced to ensure adequate sensitivity in the UV region of the emission spectrum. If the axial wavelength calibration fails for wavelengths less than 190 nm, this may indicate that the axial pre-optic window is dirty.

Steps to follow

Follow the steps in this article to clean or replace the axial pre-optic window:

Caution: Always turn off your instrument before attempting to remove the window and do not operate the instrument while the window is removed.

Warning: Hot Surface. The torch compartment and components in it become extremely hot during instrument operation and remain hot for some time after the instrument has been switched off. Allow the torch compartment to cool for at least five minutes before attempting to remove any component. Use heat-resistant gloves.

To remove the axial pre-optic window Assembly:

1. Remove the torch and snout. See Figure 1.

   
   Figure 1. Torch Compartment
   1. Axial pre-optic window assembly, 2. Cone, 3. Cone thumb screws, 4. Snout, 5. Radial pre-optic window assembly, 6. RF coil, 7. Torch

2. Remove the three cone thumb screws.

3. Pull down the Cone from the assembly.

4. Gently pull down on the axial pre-optic window assembly.

5. Tilt the top of the assembly towards the back, and then slide it to the right to remove from the torch compartment. (See Figure 2.)

   
   Figure 2. Removing the axial pre-optic window assembly

6. Check the axial pre-optic window, and replace or clean as needed.

To clean the pre-optic window

1. Soak the optics window in a dilute 5% v/v laboratory detergent for 30 minutes.
2. Thoroughly rinse with de-ionized water.
3. If the contamination is not removed, soak the pre-optics window in dilute 5% v/v nitric acid for 1 hour.
4. Thoroughly rinse with de-ionized water.
5. Rinse with clean, reagent grade isopropyl alcohol 2-propanol.
6. Dry the pre-optics window using one of the following options:
   
   • Air dry at room temperature
   • Dry in a drying oven set between 40–80 °C 104–176 °
   • Use a clean, filtered compressed gas such as argon, nitrogen, or compressed air.

Caution: Do not use hydrofluoric acid to clean the pre-optics window. Always wear gloves when handling the pre-optics window. Avoid touching the faces of the window. Handle the pre-optics window by the edges only. Avoid wiping the faces of the window to prevent scratching the window.

Warning: Chemical hazard: The cleaning procedure may involve the use of corrosive or other hazardous chemicals. Many acids, including nitric acid, are corrosive and can cause severe burns when they come into contact with the body. It is essential that appropriate protective clothing be worn always when handling all chemicals.

To install the axial pre-optic window assembly:

1. Tilt the top of the axial pre-optic window assembly towards the back of the instrument and then slide it up into the housing. See Figure 3.

   
   Figure 3. Installing the Axial pre-optic window Assembly

   Caution: Do not hit the RF coil. The axial pre-optic window assembly must be replaced before fitting the cone. The cone will not fit properly if the axial pre-optic window assembly is not installed.

2. Align the holes in the assembly with the screws and then push the assembly in.

3. Install the cone onto the assembly.

4. Tighten the three thumb screws firmly by hand.
   
   

Learn more on how to effectively troubleshoot your Agilent ICP-OES: ICPOES-5110-1270e - Agilent 5110 ICP-OES Maintenance and Troubleshooting e-learning course available from Agilent education