7
Diagnostics and Troubleshooting
Troubleshooting
Thermo Scientific
TSQ Quantum XLS and TSQ Quantum GC User Guide
135
Issue:
Chemical
background due to
rhenium oxide (
m/z
185/187, 201/203,
217/219, 233/235,
250/252).
Possible causes/solutions
• These series of rhenium oxide ions come from oxidation of the rhenium filament wire
due to the introduction of air into the ion source while the filament is on.
• Check for air leaks and remedy. See
information.
Issue:
Spectra are
observed due to the
following solvents:
Possible causes/solutions
• There is residual solvent from a cleaning procedure or laboratory background
contamination. When you finish performing a cleaning procedure, allow cleaned
components to dry thoroughly. Warm parts in the GC oven to drive off residual solvent.
• The observed compounds have been introduced through sample injection. The ultimate
source is either a sample solvent or the autosampler rinsing solvent. Optimize GC
method to separate solvent peak from the area of interest in the chromatogram.
Filament and Lens Control Issues
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.
Xcalibur diagnostics test 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 test the lenses of the TSQ Quantum XLS and TSQ Quantum GC mass
spectrometers. 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 use.
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 the lens drivers.
Solvent Spectra
Acetone (
m/z
43, 58, 59)
Hexane (
m/z
41, 43, 56, 57, 58, 85, 86)
Methanol (
m/z
31)
Methylene chloride (
m/z
84, 83)
Toluene (
m/z
91, 92)
Trichloroethane (
m/z
151, 153)
Xylene (
m/z
105, 106)