This Information Applies To: 5100, 5110, 5800, and 5900 ICP-OES instruments
Issue
The ICP-OES operator can identify the source of plasma ignition failure. The main cause is air entering the plasma.
Steps to follow
Excessive air entering the plasma. Check the following:
The peristaltic pump tubing is clamped and has sufficient clamping pressure. Usually, air is being pulled into the nebulizer because the pump tubing is not properly clamped during ignition. At ignition, the plasma is sensitive to too much air being self-aspirated into the plasma.
Check that the autosampler probe is down inside the rinse vessel and that the rinse solution is flowing properly to the nebulizer
The torch may be damaged, dirty, or not assembled correctly. Try a new torch. If the torch end is highly contaminated it can become conductive, making plasma ignition less consistent.
The torch contains liquid sample. Clean and dry the torch.
The nebulizer may have some damage and leak.
There may be a leak at nebulizer gas fitting. Check to ensure the nebulizer gas tubing from the instrument to the nebulizer fitting is tight and secure.
The spray chamber is not draining properly. If the spray chamber is not draining properly, due to insufficient pressure on the peristaltic pump pressure arms, then water droplets will go up into the torch and prevent ignition.
Check the drain tubing fitting and ensure that the rinse solution is flowing out the spray chamber properly. Always check the torch and ensure it is clean and completely dry.
A large droplet may have entered the plasma. Check that the spray chamber is clean and nebulizer is producing a fine mist. If using a single pass spray chamber, consider changing to a double-pass spray chamber.
Insufficient plasma flow and/or excessive auxiliary flow.
Work coil damaged and bent down.
Problem with ignitor. Check for a visible spark and listed for the ignition sound.
Check that the argon supply has not recently changed.
Check that there is sufficient argon supply and pressure is in the range 500 to 600 kPa (73 to 88 psi). It is better to set the pressure at the regulator to 600 kPa (88 psi) to identify possible line pressure drops. Ideally a second regulator has been installed within three meters or 10 feet of the instrument. If running 30 m of 6 mm or 1/4-" ID tubing to the instrument at 500 kPa, the line pressure drop is adequate to affect plasma ignition. If possible, watch the regulator while trying to ignite the plasma, and watch to ensure that the pressure doesn't fall below 80 psi. Raise the pressure if necessary.
This test identifies a leak in the sample introduction system.
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Warning: The plasma operates at 10,000 K. Prevent damage to the torch by turning the plasma on for a short period of time. Do not exceed 10 seconds.
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Unclamp and remove the spray chamber from the bottom of the torch. Seal the bottom of the torch with Parafilm and attempt ignition. If the plasma lights, the sample introduction system will have an air leak. Check that the nebulizer and spray chamber connections are sealed, in particular the helix seal.
Contact you local Agilent Service Center if you re unable to identify and correct the problem.
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Learn how to effectively troubleshoot your Agilent ICP-OES:
ICPOES-MULTI-2210e - Agilent 5000 Series ICP-OES Troubleshooting System Issues e-learning course available from Agilent education |
