Agilent Technologies 5975C TAD VL MSD Troubleshooting And Maintenance Manual page 222

8
Electronics
Pumpdown failure shutdown
The AC board will shut down both the high vacuum and the foreline pump if
the system fails to pump down correctly. One condition that triggers shutdown
is turbo pump speed below 80% after 7 minutes, or it the foreline pressure is
above 300 mTorr after 7 minutes.
This is usually because of a
correctly or the vent valve is still open. This feature helps prevent the foreline
pump from sucking air through the system, which can damage the analyzer
and pump.
To correct the problem, power cycle the MSD and troubleshoot. You have
7 minutes to find and correct the air leak before the system shuts down again.
Be sure to press on the side plate when turning on the MSD power to ensure a
good seal.
222
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air leak: either the sideplate has not sealed
5975 Series MSD Troubleshooting and Maintenance Manual