PerkinElmer AVIO 500, Customer Hardware And Service Manual

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Troubleshooting
• Organics. If you analyzing organic solutions and cannot ignite the plasma, run
the nebulizer argon for a couple of minutes with the pump off to purge the spray
chamber.
• Organic Vapors. If these remain in the torch from an earlier analysis, they can
sometimes cause ignition problems. If you suspect this, purge the sample
introduction system with argon for several minutes.
• Spray Chamber . Remove the spray chamber and cap the injector. Now try to
light the plasma. If the plasma now lights and is stable the ignition problem is
in the spray chamber, nebulizer or the sample introduction system. If the
problem persists check the torch O-rings and gas connections to the torch
mount.
Plasma Stability Problems
If periodic pulsations of the torch are observed:
• Poor sample drainage may be the problem. Make sure that waste drainage is
not backing up into the spray chamber and that the waste is draining properly.
• Check the condition of the peristaltic pump tubing. If it is flattened, stretched,
or damaged by abrasion, replace the tubing.
• Air leaks may be causing the pulsation. Check the O-rings on the torch
assembly and ensure that the nut on the end of the torch is firmly in place. Do
not use a tool to tighten. Make sure the nebulizer/end cap assembly fits tightly
to the spray chamber.
If using organics, you may see an irregular pulsation:
• Be sure that the injector you are using is recommended for the types of solvents
you are using. The alumina, 1.2mm injector, is recommended for typical
organic analyses. The alumina injector, 0.80 mm i.d., should be used with
volatile organic solvents, for example, methanol.
• Try increasing the RF power, using less solvent, slowing down the pump
speed, or adjusting the torch height.