Problem of suppressor for IC

[Aopeau]

I cannot adjust the flow rate ratio between suppresor to conductivity detector and suppressor to waste. My suppresor is 828 IC Dual Suppresor (Metrohm). In the manual, the flow rate from suppressor to detector is supposed to be 40% from column flow rate. That means the flow rate from suppressor to waste is supposed to be 60% of column flow rate. I cannot reduce the flow rate from suppressor to column less than 70% of column flow rate. When I tried to do it, the suppressor showed not-ready status (red light). I need help from experts or any one who encounters the same situation. Thank you very much if you don't mind giving advice.

[Markus Laeubli, Metrohm]

Dear Aopeau

Please make sure that you connected the back-pressure capillary (6.1803.090 PTFE capillary 0.25 mm i.d. / 15m ) after the detector. Only if this cappillary is connected there will be enough backpressure to get the correct flow ratio.