
5
Operating in EI Mode
Venting the MS
7000/7010 Series TQ GC/MS Operating Manual
105
Venting the MS
A program in the data system guides you through the venting process. It turns
off the GC and MS heaters and the turbo pump at the correct time. It also lets
you monitor temperatures in the MS, and indicates when to vent the MS.
The Fast Vent feature loads a user-defined GC method that sets an oven
temperature, turns off the transfer line heater, and sets the column flow to a user
predefined level.
The MS
will
be damaged by incorrect venting. A turbo pump will be damaged if it
is vented while spinning at more than 50% of its normal operating speed.
For complete venting instructions, see
WARNING
Ensure the GC/MS interface and the analyzer zones are cool (below 100 °C)
before you vent the MS. A temperature of 100 °C is hot enough to burn skin;
always wear cloth gloves when handling analyzer parts.
WARNING
If hydrogen is used as a carrier gas or JetClean system supply, the carrier and
JetClean system supply shutoff valves must be closed before turning off the
MS power. If the foreline pump is off, hydrogen will accumulate in the MS and
an explosion may occur. Read
on page 21 before operating
the MS with hydrogen gas.
WARNING
Never open the vent valve or shutdown the vacuum pumps without first
closing the shutoff valves for all hydrogen flows to the analyzer. This includes
hydrogen carrier gas and hydrogen for the JetClean system.
CAUTION
Never vent the MS by allowing air in through either end of the foreline hose.
Use the vent valve or remove the column nut and column.
Do not vent while the turbo pump is still spinning at more than 50%.
Do not exceed the maximum recommended total gas flow. (See