Sequence Options

The Sequence Options dialog serves for defining the sequence parameters. It can be opened using the icon or the Sequence - Sequence Options command of the Sequence window.

Sequence Options

Description

The description of the displayed sequence.

Sequence mode

Serves for setting the operation mode of the sequence.

Active

In an ACTIVE sequence, the sequence start is controlled by the station. Clarity sends the permission signal to the autosampler and waits until the sampler acknowledges the injection. Data acquisition will be started after the confirmation signal has been sent back to Clarity and the permission for another injection is disabled.

Caution:

When the ACTIVE sequence is used, Enable Autostop and External Start/Stop must be set in the Method Setup - Measurement dialog and the Start-Restart option of the External Start/Stop behaves as Start Only.

Passive

In a PASSIVE sequence, the start is controlled by the autosampler. Clarity only waits for external start signal from the autosampler and then starts the sequence and data acquisition.

Caution:

When the PASSIVE sequence is used, External Start/Stop must be set in the Method Setup - Measurement dialog.

Once the analysis time of the method in question has elapsed (as set in the Run Time field of the Method Setup - Measurement dialog), the analysis will be completed and injection will be permitted once again.

Note:

Only the Start In and Ready Out synchronization cables are needed for the active sequence to function. The active sequence can thus be used even with an autosampler not governed by a specialized control module.

Note:

The confirmation signal is represented by a change against the initial value of the selected digital output (e.g., change from High to Low, or vice versa). The default assignment of outputs is described in the corresponding hardware manual.

The assignment of digital inputs and outputs used for the synchronization can be changed on the tab of the appropriate Instrument in the System Configuration dialog, in the Ext. Start Dig. Input and Ready Dig. Output fields. For more detailed information, see chapter 6 in the Getting Started manual.

Idle time

Delays the sending of the permission to inject. The next injection after the end of an analysis will always be permitted only after the defined Idle time has elapsed. Possible values are within the 0.01-100 min range. This field can only be edited when the sequence is set to Active.

Idle time also before first Injection

Determines whether the Idle time parameter will be used even before the first injection in the active sequence. This field can only be edited when the sequence is set to Active.

Run lines

Sets the line numbers of the Sequence Table to be run in the measurement. Particular line numbers should be separated by a comma (e.g. 1,3,5), ranges should be entered using a dash (e.g. 1-8).

A list of lines to be run can be defined interactively using the checkboxes in the Run column of the Sequence Table (the selected lines will be automatically filled in the Run lines field).

Counter (%n)

Sets the value and properties of the %n variable (analysis counter) used in the Sequence Table.

Value of the counter increases every time an analysis (injection) is performed and a chromatogram is created.

When taking Snapshots, the value of the Counter is incremented only once, even if more than one snapshot is taken. Old snapshots are thus overwritten by new snapshots and eventually by the resulting chromatogram.

Start at:

Defines if the %n variable will be reset to 0 or 1 at the moment defined in the following Reset when field.

Reset when:

Sets the condition when the counter (%n variable) is reset. Available options are:

Run Sequence - The counter is reset every time the sequence is run.

Open Instrument - The counter is reset every time the Instrument window is opened.

Never - The counter is never reset.

Current value

This field shows (and allows to modify) the current value of the sequence counter (%n variable). Each time a chromatogram is measured the value of counter increases by 1.

Caution:

The station keeps two separate counters: one for the sequence and another one for the single analysis. This means that two %n variables with possibly different values exist simultaneously.

Solve conflict of filename

Sets the method for resolving the conflict of chromatogram names when a chromatogram with a name identical to an existing chromatogram is to be created (according to the set File Name). This may happen when measuring more than one chromatogram from a particular line or after restarting a measurement.

Automatically

The pattern will be automatically modified to correspond to the number of measured chromatograms and to avoid possible loss (overwriting) of chromatograms.

Note:

When using the automatic format, variables will be complemented by additional three-digit counter corresponding with the defined number of samples (e.g., in a sequence where SV = 1 and EV = 100, the file names will be automatically numbered from 001 to 100).

Manually

The pattern will not be modified. Once the sequence has been run, you will be notified of a possible overwriting of chromatograms.

Calibration and sequence usage

Selects the mode of the calibration and sequence usage.

Calibration used as specified by user

Sets the sequence and calibration to the standard Clarity use (the only way available since version 3.0). The calibration set in the Method Setup - Calculation dialog is used for calibration and recalibration, no calibration cloning is performed.

Clone on first recalibration (safe calibration usage)

Sets the sequence and calibration to the safe calibration usage mode. This option will create a clone (copy) of the calibration defined in the method upon completing the first row of the sequence. Cloned calibration is attached to each new chromatogram produced by the given sequence. The option is not available on EA Instruments.

Standard addition measurement

Sets the sequence to the standard addition mode (it is necessary to set the Display and Calculations mode to STDADD in the calibration and method). As each unknown sample will use one calibration file, the calibration will be cloned from the original calibration file whenever an unknown sample or blank follows the calibration standard. All responses are cleared from a newly cloned calibration. The option is not available on EA Instruments.

Calibration bracketing

Bracketing is a simplified direct calibration method used to compensate for variations in the instrument response with time.

This option sets the sequence and calibration to the calibration bracketing mode. In this mode, every unknown sample series is enclosed between calibration standards and uses a single calibration file. The calibration is cloned from the previous calibration clone whenever an unknown sample or blank follows a calibration standard in a sequence. The newly cloned calibration file has all the previous responses cleared except for the last series of calibration standards (standards that immediately precede the current unknown sample).

Calibration bracketing will work correctly only if the used calibration has the Recalibration option selected and set to Average (at least 2 points) in the Calibration Options.

In the EA mode, the name of the cloned calibration file is hard-set as the original name incremented by the sequence line number (%L parameter).

Note:

At each calibration cloning, the original calibration and thus the results of the chromatograms measured earlier are preserved, under the name as set in the Method Setup - Calculation dialog, Calibration Cloning In Sequence option (conflicting names will be complemented by a three-digit counter to avoid overwriting).

After sequence is finished

Allows to set actions to be performed when the sequence is finished

Send shutdown method

Specifies a method to be sent to the instrument when the sequence is finished. The method can be selected using the button. The button allows to edit the currently selected method.

If no other options are checked, Clarity will send the parameters of the specified method to the instrument and no acquisition will be performed.

Run shutdown method

An analysis according to the specified method will be performed. The resulting chromatogram will be saved to the current project as <SequenceName> - Shutdown - <MethodName> - %R.prm

Sample type

Sets the type of the sample being measured by the shutdown method. The possible options are:

  • Unknown - a controlled autosampler will perform an injection
  • Bypass - no injection will be performed

Vial no.:

The vial number / injection number of the given vial. If the configured autosampler supports graphical interface for inserting vial number, the button is present - clicking this button invokes the Select Vial dialog for selecting a vial.

Inj. vol. [units]:

Defines the volume of injection. The present units are as set in the Instrument Units dialog available in System Configuration.

Note:

Several autosamplers require specific values for the Vial no. or Inj. vol. although no injection is performed. If these values are missing, the user is informed during the validity check.

Perform shutdown

When the sequence is finished, all connected controlled devices will be shut down. The shutdown command is sent after sending (and possibly completing) the run of the shutdown method. When the shutdown method is just sent and no shutdown method run is performed, invoking the shutdown does not wait for the controlled instruments to become ready.

Caution:

The parameters of the After sequence is finished section are also executed when the user stops the sequence by the Stop command or the sequence is stopped by an error. If it is necessary to stop the running sequence without sending (and running) the shutdown method, use the Abort command.