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CI Troubleshooting
3
Troubleshooting and Maintenance Manual
55
There should not be any peak visible at
m/z
32 (O
2
). This almost always
indicates an air leak.
Special NCI notes
Since NCI is so extremely sensitive, air leaks that are not detectable in EI or
PCI can cause sensitivity problems in NCI. To check for this kind of air leak in
NCI, inject OFN. The base peak should be at
m/z
272. If the abundance of
m/z
238 is much greater than that of
m/z
272, you have an air leak.
How do I find the air leak?
1
See
.
2
Look for the last seal that was disturbed.
•
If you just pumped down the MS, press on the sideplate to check for
proper seal. Poor alignment between the front analyzer and the GC/MS
interface seal can prevent the sideplate from sealing.
•
If you just replaced the reagent gas bottle or gas purifier, check the
fittings you just opened and refastened.
Figure 2
Looking for air leaks
Содержание 7000 Triple Quadrupole GC/MS
Страница 24: ...24 Troubleshooting and Maintenance Manual 1 Introduction...
Страница 50: ...50 Troubleshooting and Maintenance Manual 2 General Troubleshooting...
Страница 122: ...122 Troubleshooting and Maintenance Manual 4 General Maintenance...
Страница 144: ...144 Troubleshooting and Maintenance Manual 6 Vacuum System...
Страница 182: ...182 Troubleshooting and Maintenance Manual 8 Electronics...
Страница 193: ...Replacement Parts 9 Troubleshooting and Maintenance Manual 193 Figure 45 Foreline pump top and safety cage parts 1 6 5 7...
Страница 212: ...212 Troubleshooting and Maintenance Manual 9 Replacement Parts Figure 50 CI flow control module 5 3 4 2 1...
Страница 213: ......
Страница 214: ...Agilent Technologies Agilent Technologies Inc Printed in USA September 2009...