Varian 4000 GCMS, Installation Procedures Manual

Page: 19 / 63

03-914998-55:6
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Turn on the ion trap
briefly
, take a quick glance at the spectrum, and then turn
off the ion trap. If the system is pumping down as expected, there should be one
large off scale peak on the display centered around 19 m/z and a smaller
(typically 10-50% full scale) peak around 32 m/z. There should not be a
significant 28 m/z peak visible. (Refer to Figure 2.8.) If there is the system has a
leak which needs to be found and fixed. If the system has a significant leak, the
baseline will be flat, or there will be one large, broad peak from about 15 - 35
m/z. If this is the case, then the leak should be found and corrected before
progressing any further with the installation. After the system has been pumping
for > 30 minutes the intensity of the 18/19 m/z signal will decrease and the 28
m/z signal should appear.
Figure 2.8