Definition of "Posttime"

Hi all, I use Agilent ICF on Waters Empower software and would like to know the definition of "Posttime". I have looked online but cannot find a clear definition

For example, I have a total gradient of 30 min including ~6 min of equilibrate at the end. If I define a 5 min posttime and set the run time as 30 min, what will be the overall injection behavior?

1) Will a 5 min be appended to the end of each injection makes it 35 min (30+5)? Or no data collection from 25 min (30-5)?

2) Which mobile phase composition of posttime will follow? The last line of event table, or the first line, or at 25 min (30-5)? 

Thanks a lot

  • Hello,

    Posttime is after the stoptime and will run at the final conditions before returning to initial conditions. In your example, you could do a 25-minute stop time, then a 4-minute post time, and remove the 30 minute step from the timetable. Your data file signal would be done at 25 min but the post time would allow the full 5 min equilibration.   Please note the run stops data collection based on at least one module stop time not the timetables. I will assume in the screen shot attached you stoptime is set in the injector module. 


    From help

    Your instrument remains in a post-run state during the posttime to delay the start of the next analysis. You can use the Posttime to allow your column to equilibrate after changes in solvent composition (for example after gradient elution).

    Limits: 0.01 to 99999 minutes or Off (0.0 minutes).

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