Specifications
274 5975 Series MSD Troubleshooting and Maintenance Manual
Index
mass (axis) offset, 210
parameters, 208
radiator, 213
RF voltage, 208
Mass gain, 210
Mass offset, 210
Mass spectra
high abundances at m/z 18, 28, 32, and
44 or at m/z 14 and 16, 39
high background, 38
inconsistent peak widths, 39
incorrect mass assignments, 39
isotopes missing or ratios are
incorrect, 38
precursors, 39
Mass-to-charge ratio, 208
Methane/isobutane gas purifier
replacing, 167
Micro-ion vacuum gauge
ignition of hydrogen by, 195
reinstalling, 117
removing, 116
Mist filter, for foreline exhaust, 176
Moving the MSD, 94
MS error numbers, 47
MSD
dangerous voltages in, 85
dangerously hot parts in the, 86
does not turn on, 31
electronics, 215 to 229
hazards from chemical residue, 86
interfacing to external devices, 228
maintaining, 83 to ??
moving or storing, 94
troubleshooting, 29 to 54
N
NH3, preventing damage to the foreline
pump due to, 166
No peaks in CI MSD, 69
O
Oil drip tray, for foreline pump, 176
Oil trap, 176
Oil tray, for foreline pump, 176
On/off switch. See Power switch
Ordering parts, 232
O-rings and O-ring assemblies, 182
P
Parts, 231
analyzer, 250
consumables, 260
electronic, 233
if you cannot find a part you need, 232
ordering, 232
rebuilt assemblies, 232
vacuum system, 240
Parts, replacement, 231
Peak widths, inconsistent, 39
Peaks
at m/z 18, 28, 32, and 44 or at m/z 14
and 16, 39
flat tops, 34
fronting, 34
inconsistent widths, 39
missing, 33, 49
precursors, 39
split tops, 35
tailing, 34
PFDTD
not visible, but reagent ions are
present, 73
PFDTD
(perfluoro-5,8-dimethyl-3,6,9-trioxidod
ecane), 192
PFTBA (perfluorotributylamine), 192
Physical description of MSD, 13
Polarity (dc), of the mass filter, 210
Power cord
ac, 225
foreline pump, 225
receptacle, 225
Power supplies
high voltage (HED), 224
low voltage (ac-dc), 224
Power switch, 217
Pressure
analyzer chamber pressure too high, 42
analyzer chamber pressure too low, 43
CI ion source, 202
does not change when reagent gas flow
is changed, 67
foreline pressure too high, 42
foreline pressure too low, 43
Ion source, for CI, 16
symptoms indicating malfunctions, 42
too high in analyzer chamber with
reagent gas flow, 66
too high in analyzer chamber without
reagent gas flow, 65
Procedure, 166
Pump
exhaust, venting, 86
Pump oil drip tray, 176
Pump, foreline
failure to turn on, 32
turned off during pumpdown, 32
Pumpdown
failure, 222
safety shutdown, 174
Pumpdown safety shutdown, 222
Pumping problem, 222
Pumps turned off, 174, 222
Q
Quadrupole. See Mass filter
R
Radiators, 213
Reagent gas
cleaning supply tubing, 168
Reagent gas ions
not visible, 71
Relative abundance, 40
Remote start connector, 225, 228
Repeatability, poor, 37
Repeller, CI, 202
S
Safety
covers, 85
during maintenance, 85 to 87
Seals
vacuum, 182
See also O-rings and O-ring assemblies
Sensitivity
poor, 37
poor at high masses, 41
Septum bleed, as a source of
contamination, 54