How to specify a DOE constraint with a categorical and continuous factor?

[#1]

In a DOE HPLC optimization study I have a two level categorical factor column (A & B) and a continuous factor flowrate. For column A the flowrate range is 0,5 - 2 ml/min but for flowrate B the range is more narrow i.e. 0,5 - 1 ml/min. How can I make a constraint so that there are no combinations column B with flowrate > 1 ml/min?

[#2 · Accepted solution]

Hi Frank, Disallowed Combinations in Custom Design should enable you to do this. You can specify the combination of Column B AND Flowrate > 1 as a combination that should be diasllowed.

[#3]

Thanks Phil! Frank