User`s guide

Installation and Setup
81
2. Select Outlet Split. This opens the solenoid valve on
the outlet split vent.
3. Connect a flow meter to the split vent and use the outlet
split needle valve to adjust the flow rate. A minimum
flow of 3 mL/min is recommended.
NOTE: If a column carrier flow rate of less than the required
minimum trap flow is used, then use the outlet split flow to
make up the difference.
4. If you did not measure the actual column flow
previously, use the reference tables in the Appendices to
determine the flow over the GC column. Record this
value as you may need it later in order to calculate
sample split ratios.
5. Press the Stop button to close the outlet split flow
solenoid valve and return the instrument to the Ready
state.
NOTE: Recheck the flows when you are actually running a sample,
as the flows may be different when heat is applied.
It is possible to desorb the trap efficiently at flows as low as 3 to 5
mL/min. However, superior results will generally be obtained if a
higher split flow is used. This considerably increases the gas velocity
through the trap during trap heating.