Thermo Scientific ISQ, User Manual

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4
Creating a Method
Creating a Method for the GC
Thermo Scientific ISQ User Guide 55
operating temperature of your GC column. If you set the initial temperature to a value
below this limit, the GC will not reach the initial temperature. If you set the temperature
above the limit, the GC column will get damaged. You can set the initial hold time to a
value between 0 and 600 minutes. The typical initial temperature is at least 10 °C above
the boiling point of your sample solvent and the initial time is usually long enough for the
solvent to move through the column.
Figure 42. Setting the FOCUS GC Oven Parameters
a. You can select a maximum of seven temperature ramps, each with their own ramp
rates, final temperatures and hold times. A typical program will have one or two
ramps. However, the GC temperature profile is the primary method for separating
your analytes from each other, the solvent, and the matrix. Your temperature profile
will have to be optimized for your analysis needs.
b. You can also select the maximum allowed oven temperature, which should be set to
the maximum temperature allowed by your column. This will prevent you from
accidentally using a temperature that will damage your column. The prep-run
timeout is the maximum amount of time that the GC will wait before it gives up on
an injection. As an example, with a default value of 10 minutes, if the GC is ready to
receive an injection, but does not receive it after ten minutes, the GC will stop
waiting. This usually occurs in case of an error. The equilibration time is a delay
between when the GC is at temperature and when the GC reports as being ready.
This delay is typically set to 0.1 minutes.
CAUTION - INSTRUMENT DAMAGE. Be sure not to overheat the GC column or it may
contaminate the ISQ instrument.