Total Flow

Hi camelia,

That is a puzzle. I cant think of anything except to examine both methods. Can you post the method parameters? Are both methods run on the same inlet and detector?

I updated the tags on the  post for better visibility.

Regards

James

Hi James

I have attached the 2 methods for you to examine. The methods are run consecutively using the same column, inlet and detector

Best Regards

Hi camelia,

The total flow in split flow  equation( Total flow =septum purge vent+ split vent+ column flow) ,So I think the difference in septum purge vent value, for method 1 the septum purge vent equal to 2.2ml/min and for method 2 equal to 1.1

check septum purge vent will solve the  puzzle

Another thing look a little and recommended septum purge vent 3ml/min 

  Dheya 

Hi,

I don't think its possible to set the septum purge flow on the 6890N GC ? Please let me know how to do this if it is possible.

Thanks

Hi camelia,

I don't have a good explanation for this. Some things I notice that could play a factor. It looks like the DB1 specifications may have been entered manually?   This should still not make a difference. Have any of the columns been flow calibrated? Method 1 is isothermal while method two is a an oven ramped (temperature) method again, at start, shouldn't make a difference with constant pressure with the same start temperature. I welcome other community members input. The difference will not create a problem with method functionality.

Regards

James

Septum purge is set automatically on 6890, it is not possible to set it to a specific value.  From 6890 User Info: