INFICON Explorer Portable Gas Chromatograph - Manual (Page 197)

Explorer Operator Manual
195
If minimizing the pump time is critical for your application, you must confirm
correct offset adjustment.
1. Set the pump time to 10 seconds.
This is the minimum value for the pump time.
2. Perform 3-4 analyses on each active column. For each analysis, monitor the
signal level at the end of the pump time.
The baseline should be approximately 2 mV if the PID sensitivity is set to high
and approximately 200 mV if the PID sensitivity is set to low.
3. If the baseline has not been set correctly, then the pump time is too short.
Increase the pump time and repeat this procedure.
NOTE: If your method incorporates a switch in gain between analyses, then the pump time
must be set to 20 seconds.
Injection Time
Injection time determines how long the sample loop is in line with the column and in
turn, the volume of the sample that is injected onto the column. Injection time has no
effect on syringe injection. Setting the injection time to 10 seconds will inject the
entire contents of the sample loop onto the column. The volume of the sample loop
is 0.5 mL.
Explorer is a very sensitive instrument. It is easy to overload the column and
detector by injecting a sample that is too large. Normally, you will set the injection
time to between 0.4 and 2 second. You may want to start with a short injection
time, perform a run and increase it to obtain the best results.
1. Press Enter Menu, SETUP, CONFIG, COLUMN.
2. Select the column for which you want to alter the injection time. Disable the
other columns.
3. Press Exit to close the box. Press Enter Menu to close the menu.
4. Press Enter Menu, SETUP, CONFIG, METHOD, TIMING, and INJECT.