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2
Installing 8890 GC Columns
Columns
30
7000/7010 Series TQ GC/MS Operating Manual
Columns
Many types of GC columns can be used with the MS, but there are some
restrictions.
During tuning or data acquisition, the rate of column flow into the MS should not
exceed the maximum recommended flow. Therefore, there are limits to column
length and flow. Exceeding recommended flow will result in degradation of mass
spectral and sensitivity performance.
Remember that column flows vary greatly with oven temperature, requiring
measurements of the actual flow to be taken. Use the flow calculator in the
Agilent Instrument Utilities software, and
to determine an acceptable
column flow. EI and CI systems also have different column outlet flow pressures.
(See
for CI mode.)
Table 3
Gas flows
Feature
Gas flows
High-vacuum pump
Split flow turbo
Optimal He column gas flow, mL/min (carrier gas)
1 to 2
Reagent gas flow, mL/min
1 to 2
CC gas flow
3 to 4
Maximum recommended gas flow, mL/min
*
* Total gas flow into the MS = column flow + CC gas flow + reagent gas flow (if applicable) + JetClean
H
2
flow (if applicable)
4 to 6
Maximum gas flow, mL/min
†
† Expect degradation of spectral performance and sensitivity.
6.5
Maximum column id
0.53 mm (30 m length)
JetClean option H
2
flow,
0.4 mL/min