Pressure-Related Symptoms - Agilent Technologies 7250 Troubleshooting And Maintenance Manual

3 CI Troubleshooting

Pressure-Related Symptoms

The following symptoms are all related to high vacuum pressure. Each symptom
is discussed in more detail in the following pages.
The mass flow controller is calibrated for methane and the high vacuum gauge
controller is calibrated for nitrogen, so these measurements are not accurate in
absolute terms
readings. They were taken with the following set of conditions:
Source temperature
Quad temperature
Interface temperature
Helium carrier gas flow
Table 5 Typical analyzer vacuum with reagent gas flow
 
MFC (%) Rough pump
0 1.36e+02
10 1.36+02
15 1.43+02
20 1.5+02
25 1.57+02
30 1.63+02
35 1.69+02
40 1.74+02
7250 Accurate-Mass Q-TOF Troubleshooting and Maintenance Manual
(Table 5). They are intended as a guide to typical observed
Collision cell gas flow on
N = 1.5 mL/min
2
Quadrupole Flight tube
(Torr) (mTorr)
3.62e-05 3.35e-07
3.62e-05 3.37e-07
3.66e-05 3.37e-07
3.71e-05 3.39e-07
3.73e-05 3.41e-07
3.77e-05 3.41e-07
3.81e-05 3.41e-07
3.83e-05 3.43e-07
300 °C
150 °C
280 °C to 320 °C
1 mL/min
Collision cell gas flow off
N = 0 mL/min
2
Rough pump Quadrupole
(mTorr) (Torr)
9.13e+01 5.98e-07
1.14e+01 1.27e-06
1.23e+01 1.62e-06
1.31e+01 1.96e-06
1.39e+01 2.32e-06
1.46e+01 2.64e-06
1.52e+01 3.00e-06
1.58e+01 3.34e-06
Flight tube
(Torr)
1.64e-07
1.65e-07
1.67e-07
1.67e-07
1.70e-07
1.71e-07
1.71e-07
1.72e-07
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