Thermo Scientific DSQ II, Hardware Manual

Page: 146 / 242

3
Troubleshooting
Filament and Lens Control Symptoms
130 DSQ II Hardware Manual Thermo Scientific
Filament and Lens Control Symptoms
The lifetime of a filament depends on its exposure to oxygen and solvent vapors. The filament
assembly protects the filament and increases its lifetime for many months.
Tune diagnostics tests the filament for continuity and current regulation. Testing the filament
for continuity before each acquisition ensures that an open filament condition will stop an
autosampler sequence and generate an error message.
Diagnostics tests the lenses of the mass spectrometer. A flat line, which represents voltage
readback versus the predicted voltage ramp, indicates a lens or other control fault.
Contamination causes lens performance to deteriorate over time; the amount of time depends
on what type of sample and ionization mode you are using. Be careful to handle the lenses
with care, and do not use harsh cleaning techniques. Damaged lenses cause short circuits,
which in turn can cause damage to lens drivers.
Diagnostics indicate filament is open.
Possible Solutions
Vent the system and remove the filament, as described in “Cleaning the Ion Source, Lenses
and Prefilter” on page 45 . The resistance of a working filament is about 1.0
Ω
. If the measured
value is very large, replace the filament.
Inspection indicates filament is good, but diagnostics still indicates filament is
open.
Possible Solutions
• There is a fault in the ion source board. Replace the ion source board, as described in
“Cleaning the Ion Volume Without an Inlet Valve” on page 43 .
• The cable connection between the analog and lens interface board is defective. Check the
connection, as described in “Replacing the Lens Interface Board” on page 96 .
• There is a problem with the analog board. If necessary, replace the board, as described in
“Replacing the Analog Board” on page 71 .