Choosing a different plate type resulted in high pressure?

<p>Dear All,</p><p>one of our lab members chose a different plate type (ANSI 48 tube 0.65 ml holder instead of ANSI 48 vial 2 ml holder) an error message appeared and after correcting the plate type and reset the instruments the system pressure become very high</p><p>flow 0.1 ml/min ------------ 10000 psi even without connecting the column !!!</p><p>please advise.</p><p></p><p>Regards,</p><p>Mahmoud</p>


  • I'm assuming this is an FTN.  During idle state the needle and seat are part of the flow stream.  An incorrect plate configuration may have caused the needle to be driven into the vial cap, and damaged/clogged the needle.  This would restrict the flow path prior to the column, and show an increase in pump back pressure.  With flow set very low, 0.05mL/min, you can go to the ACQUITY console and select the FTN interactive view.  Click on control and set the inject valve to load.  If you see a decrease in back pressure from the column, compared to having the valve in the inject position, it could indicate that you have a restriction somewhere in the needle, seat, or tubing that returns to the inject valve.  You'll have to move quickly once you set flow so that you can switch the valve position before the system goes to overpressure.  If it seems that you do have a restriction, replace the needle and seat, perform z axis calibration, calibrate the needle seal, and run the needle seal readiness test.  Only use the ANSI plate configurations.  Hope this helps!