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3 CI Troubleshooting
The signal cable is not connected.
Check and, if necessary, reconnect the signal cable.
The filament or filament support is shorted to the ion source body or repeller.
Inspect the filament, if necessary, realign the filament support arms.
The electron inlet hole is blocked.
Inspect the electron inlet hole and, if necessary, clean the hole with a clean
toothpick and a slurry of aluminum oxide powder and methanol. If the
electron inlet hole is that dirty, the entire ion source probably needs to be
cleaned.
Ion source wires are not connected, or incorrectly connected.
Inspect the repeller. Ensure the repeller lead is firmly attached to the repeller.
Inspect the wires to the ion focus and entrance lenses. If the connections are
reversed, correct the problem.
One of the detector leads (in the analyzer chamber) is not connected.
Check and, if necessary, reconnect the electron multiplier leads.
Saturated methane/isobutane gas purifier
Replace the gas purifier.
Poor quality methane (purity below 99.99%)
Replace the methane with high-purity methane. If necessary, clean and purge
the reagent gas lines and clean the ion source.