Chromatography Forum

I'm quite beginner with GC (i usually use LC/MS when possible).
I try to know the good parameters for my analysis, we are using a PE autosystem XL GC with a VarianVF5 colum 0.25mm,0.25µm-15m flushed with He. We use the colum between 50 and 200°c and the detector is an FID. What must be the carrier gas flow ? i tried to calculate with the HP software but i don(t understand every fields to fill: i.e Inlet Temp (C) is Injector temp ?, or Inlet pressure(gauge)= ?, Is Outlet flow the carrier gas flow i must setup ?
Please Help me !

Hi Provetech

Yes i.e Inlet Temp (C) is Injector temp indicate in your method
Inlet pressure(gauge)= is the pressure you put in your column head also in your method
And Outlet flow is the column flow you looking for.

But if you don't want to use HP software and if your system PE only regulate in constant pressure, put 7 to 8 psi in column head to start , it 's corresponding approximatively to the optimum condition of pressure for your column geometrie in He.

In other hand if the system can regulate in constant flow put 1 ml/min on your column it will be OK (it's the best regulation mode in the absolute !!)

Thank you i'll try this.

You will have to check the manual and mode you're running that GC in - if memory serves, it has mass flow control options too...