Clarity discussion forum

I'm using Clarity version 3.0.4.444, with Dani Spa Master DHS autosampler and Dani Spa Master GC and I noticed a difference of the policy in the two following tests:

1)You start a sequence and a message about a conflict on the chromatogram file name is displayed (see attachment "conflict on file name")
You chose not to continue.
From this point you are not allowed to delete any of the line of the sequence until you select all the lines and reset the status for all of them.

2)You start a sequence with different lines and one of the line has a compatibility problem (e.g. Inj.Vol.= 0): the correspodent message is displayed (see attachment "injection volume error").
You can delete that line without resetting the status."

Best regards

Barbara G

Dear Barbara,
The behaviour you describe is greatly influenced by the autosampler you use and is supposed to work this way. You see, the DANI MASTER DHS is headspace sampler and works with the sequence as with the whole, thus locking all rows at the start of the sequence. Other samplers may work differently - normally only the active row (or one more row) is locked, while others are available for editing.
In the Run sequence operation, several tests are hidden whose impact on the analysis differs. The test for the injection volume is one that is forced upon the user - you cannot start the analysis while the injection volume is set wrong. The sampler will try to use the defined volume and, if set wrong, would return error, stopping the analysis. The value is also used later for some calculations.

The file name check is a different matter. If you press the "No" button on the emerged error message, Clarity will behave exactly as for the injection volume, never running the sequence (and never locking any rows) until the issue is corrected and the sequence is run again. On the other hand, sometimes the sequence may use a variable that will surely change between analyses, but Clarity evaluates the current state of the variable, which would suggest the same file name for several samples. This is common for analyses where the analyse is governed by external source and Clarity knows nothing for example on the analysis length, but the time is used as a variable. In such case, the user may want to run the sequence anyway as he knows the file names will come in the correct form, not overwriting older files. The headspace sampler just locks the whole sequence, no just the active row.

On a slightly different note, be aware that with samplers using the overlapped sample preparation (headspace, sequence mode, ...) you may experience unusual behaviour when they encounter unexpected problems - missing vials, further start inputs etc. Use these options with care.

Best Regards,
Daniel Mentlik

Dear Daniel,

maybe I was not very clear in my explanation.

You say "If you press the "No" button on the emerged error message, Clarity will behave exactly as for the injection volume, never running the sequence (and never locking any rows) until the issue is corrected and the sequence is run again."
In my test 1, I pressed the No button and as you say the sequence never started. But at this point, even if I was not in run, all the lines of the sequence were blocked and I could not delete them.
I think this is not the right behavoiur...

Best regards

Barbara Galbiati

Dear Barbara,

as mentioned earlier, the DHS sampler works in so called sequence mode. In this mode, several injections are sent to the sampler at once to allow preparation of the next sample during acquisition of the previous one. In this mode all sequence lines, which could be processed as one step, will be locked (grayed out) at sequence start.

When some error in added sequence line is detected (like invalid injection volume or duplicate sample name), the sequence will be paused. The currently running acquisition (i.e. all locked lines) are still being processed. it gives the user the chance to remedy the error and press resume to continue the sequence.

No guarantee this will work correctly in the sequence mode.