Agilent Technologies 5975T LTM GC/MSD, Руководство по устранению неисправностей и техническому обслуживанию

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Introduction
1
Troubleshooting and Maintenance Guide 21
Precautions
Take the following precautions when operating a GC/MSD
system with hydrogen carrier gas.
Equipment precaution
You MUST make sure the front side-plate thumbscrew is
fastened finger-tight. Do not overtighten the thumbscrew; it can
cause air leaks.
General laboratory precautions
• Avoid leaks in the carrier gas lines. Use leak-checking
equipment to periodically check for hydrogen leaks.
Mass spectrometer manual
shutoff valves closed Some mass spectrometers are equipped with
manual foreline pump shutoff valves. In these
instruments, the operator can close the
shutoff valves. Closing the shutoff valves does
not shut off the flow of carrier gas. As a result,
hydrogen may slowly accumulate in the mass
spectrometer.
Table 3 Hydrogen accumulation mechanisms (continued)
Mechanism Results
WA R N I N G
Once hydrogen has accumulated in a mass spectrometer, extreme
caution must be used when removing it. Incorrect startup of a
mass spectrometer filled with hydrogen can cause an explosion.
WA R N I N G
After a power failure, the mass spectrometer may start up and
begin the pumpdown process by itself. This does not guarantee
that all hydrogen has been removed from the system or that the
explosion hazard has been removed.
WA R N I N G
Failure to secure your MSD as described above greatly increases
the chance of personal injury in the event of an explosion.