FAQ's

DATAWORX the next generation in laboratory data systems

FAQ's

Delta - Frequently Asked Questions

This section is provided for existing Delta users or for those who may be evaluating the demonstration version and require quick answers to some of the questions we get asked most frequently.

Why ?

Why does DELTA use logical printers LPT1, LPT2 and LPT3 instead of just allowing the user to select from printers available to the workstation ?

How do I ?

	INSTALL DELTA FOR REPROCESSING
	EXPORT CHROMATOGRAM DATA POINTS TO A (SPREADSHEET COMPATIBLE) TEXT FILE
	PRODUCE SYSTEM SUITABILITY REPORTS
	SET THE NUMBER OF DECIMALS PRINTED ON REPORTS
	ALTER THE WAY STRIPCHARTS ARE PLOTTED
	ALTER THE ‘SOURCE’ COLUMN FOR A SAMPLE SEQUENCE
	RE-PRINT A SAMPLE RUN
	LIST A SAMPLE SEQUENCE TO A PRINTER
	LIST A METHOD TO A PRINTER
	ABORT A RUN IN PROGRESS
	TRUNCATE A CHROMATOGRAM BEING COLLECTED
	EXPORT RESULTS TO SPREADSHEET / ASCII FILE(S)
	EXPORT RESULTS TO EXCEL^tm COMPATiBLE SPREADSHEET FILE(S).
	USE THE AVERAGE OF STANDARDS IN A RUN

What if ?

	PRINTED COPIES OF A CHROMATOGRAM REPORT DON’T PLOT THE CHROMATOGRAM
	I RE-INTEGRATE AND MY CHROMATOGRAM REPORT REMAINS THE SAME
	I MANUALLY EDIT INTEGRATIONS AND MY CHROMATOGRAM REPORT REMAINS THE SAME
	A PEAK REMAINS UNIDENTIFIED EVEN THOUGH THE COMPONENT TABLE HAS AN ENTRY WITH THE CORRECT TIME AND WINDOW
	SOME RESULT COLUMNS ARE MISSING FROM A SUITABILITY REPORT
	ALTERING METHOD STRIPCHART SETTINGS DOESN’T AFFECT RE-PRINTED REPORTS

INSTALL DELTA ON A STAND ALONE COMPUTER FOR REPROCESSING

For many years we offered a reprocessing version of DELTA for use by users who had purchased DELTA and wanted to develop methods or process their chromatograms on a PC other than the one running the data collection interface.

Whilst in the past we supplied these reprocessing versions for a modest price, it's not really our main focus for generating income and tracking licenses for these systems is more troublesome than it's worth.

So, we have decided to make the re-processing version available to everyone at no charge. This means that, in addition to the traditional use where existing DELTA owners use the reprocessing version for the reprocessing and method development, the reprocessing version may be used for teaching purposes.

When running in reprocessing mode, DELTA obviously has no data interface from which to collect data. So, DELTA takes data from a chromatogram file in it's working directory (demo.raw) and plays it in an endless loop through the data inputs, this is what you see in the Interface status window while reprocessing.

The data input stream is reset to the beginning of the pre-recorded chromatogram whenever the Start button in one of the the Interface Status windows is clicked in order to begin data collection. This allows complete emulation of a running system including data collection, and makes DELTA ideal for tuition purposes.

In addition, while DELTA is not running, any chromatogram already collected (or one of the supplied chromatograms from the deltaw\data directory) may be copied over the supplied demo.raw chromatogram. Then when DELTA is re-started the new chromatogram will be replayed through the data inputs.

Until we create an installer that allows you to choose between installing a live or reprocessing version the procedure is manual...

So, let's get to it ...

Download the latest production version of DELTA from the downloads page.
Extract the files from the downloaded zip file to a temporary directory and run the setup.exe filein that directory to install. Follow the prompts, the usual install folder is C:\DELTAW.
Right click on the Windows Start button at the lower left of the screen.
If running Windows NT/200/XP select Explore all Users, otherwise select Explore.
Now, navigate to Start...Programs...Delta Chromatography
Right click on the 'DELTA 5.0' shortcut, then select Properties.
Add the command line switch ' /reprocess' to the Target field so that it reads similar to ...

C:\DELTAW\DELTA5.EXE /reprocess

(note the space between DELTA5.EXE and /reprocess) and click the Ok button.

That's it, select Start...Programs...Delta Chromatography...DELTA 5.0 to start your reprocessing version of DELTA. After DELTA has started, select Status...Input Signals, then maximize the status window and select Channels...Tile to display the emulated input signals.

Now that you're convinced... you can run this version of DELTA as if it were a full licensed version, without any time limits. Just a reminder that the manual is in the file deltaman.pdf in the DELTA installation directory, and that the F1 key is your friend. The F1 key is not just the manual on line, it often contains instant tips that aren't in the manual and is sometimes context sensitive down to a field level.

Enjoy !!!

Why does DELTA use logical printers LPT1, LPT2 and LPT3 instead of just allowing the user to select from printers available to the workstation ?

DELTA allows a user to map the printer names LPT1, LPT2 and LPT3 to any available printing device using the Setup...Printers dialog.

During a sample run, Delta can produce up to three reports for each chromatogram processed. The destination printer for these reports is specified in the method. If we allowed these method settings to point directly to a printer such as "\\server-name\BigFastPrinter" and the printer was subsequently replaced by one with a different name, then all of the methods would require editing before they could be used with the new printer. In addition, having the methods just specify LPT1,LPT2 of LPT3 allows us to help users debug their methods without concern for the local printer names.

EXPORT CHROMATOGRAM DATA POINTS TO A (SPREADSHEET COMPATIBLE) TEXT FILE ?

In any of the chromatogram windows (eg Interactive Graphics). Click on the 'Operations' button then Select 'Save as Text File". You will be presented with a file dialog box where you must enter the name portion of the output .PRN file. After selecting OK the chromatogram data will be written to the text file. The text file contains a header where each line contains information about the original chromatogram followed by 'DataPoints' pairs of data point values each on a new line. Each data point pair represents (retention time in seconds),(voltage in microvolts)

PRODUCE SYSTEM SUITABILITY REPORTS ?

System suitability reports calculate and report a number of values for each component which are useful firstly in determining in a quantifiable manner whether a methodology is producing chromatograms with acceptable peak separation, geometry, and reproduceability. Once a methodology is accepted suitability reports may be produced during sample runs in order to verify that the system is continuing to perform in the manner reported when the methodology was first developed. Variations in results may be used to detect column deterioration, variations in carrier flow rate, column overload, etc.

Using the supplied default system suitability report as a basis, users may design their own special reports which may include flagging to indicate that certain parameters are falling outside pre-determined bounds.

A suitability report prints the following values for each identified component :

1. Name

2. Plate Count (Number of theoretical plates)

3. Plates / metre

4. Capacity Factor

5. Separation Factor

6. Peak Symmetry

7. Peak Resolution

9. Area RSD % (for average report only)

Each of these excepting the name is described below :

Plate Count : This is a measure of the sharpness of peaks and is therefore an indicator of the efficiency of the column. The greater the plate count the higher the efficiency. This figure is proportional to the square of the peak width divided by the retention time.

Plates / metre : This is simply the plate count divided by the column length. Normalising the result to plates per unit length of the column gives a figure that can be compared between columns of different lengths, note that the retention time is relevant when making such comparisons.

Capacity Factor: This is a measure of how long the component is retained on the column. It is calculated by taking dividing the time between an unretained peak and the component by the retention time of the unretained peak.

Separation Factor : This is always reported for the second of two components and is the ratio of the retained time of the second peak to the retained time of the first peak. The separation factor is not an indication of the efficiency of a column as it doesn’t take the peak widths into account.

Peak Symmetry : This is a measure of peak symmetry at five percent of peak height (above baseline). For a perfectly symmetrical peak the result would be one. This result increases with increasing peak tailing.

Peak Resolution : This is a measure of peak separation and column efficiency. It is always reported for the second of two consecutive components and is calculated by dividing the difference in retention times of the two peaks by the average of the estimated peak width at base.

Area RSD % : This is a measure of system reproduceability (precision) which can be affected by varying injection volumes, temperature drift and a number of other system variables. The RSD % is only reported if the # of Vials figure on the sample sequence is greater than one. If this is the case then the report for each individual will not be printed if the method Multi-Injection report setting in the Edit...Method...Run Control settings is set to Average Only.

The component number of an unretained peak (called the unretained solute) must be supplied in order for capacity ratio to be calculated. To calculate the Plates/metre value the column length must also be supplied. These values are entered into the method by opening the method component table editor (Edit...Method...Component Table) and selection the Options...Suitability Settings and enter the component number for the unretained solute and the column length. If these values aren’t entered warning messages will be printed in the suitability reports. The warning messages are printed by conditional fields embedded in the suitability report, if you change the reports so that plates / metre, capacity ratio and separation factor aren’t printed you may choose to create a new suitability report removing the fields that print the warning message, do not under any circumstances alter the default report named SUIT.REP. Report details are discussed in the following paragraph.

To obtain a system suitability report the Type field in a sample sequence line must be set to Suitability. When a line of type suitability is processed DELTA uses either the report template specified in Edit..Method..Run Control...Suitability Reports or, if none is specified the default report template named SUIT.REP is used. The report template named SUIT.REP uses computed fields to calculate and report the parameters listed above. If you design your own report you should load SUIT.REP, modify it as desired then save it with a different name in the same directory as your method. Following this ensure you have entered the name of the new report template in the Suitability Reports section of the method as outlined above. Be careful not to alter any of the expressions in the calculated fields, we can’t take any responsibility for the results printed by modified reports.

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SET THE NUMBER OF DECIMALS PRINTED ON REPORTS

The number of decimals printed in any field of a report generated by DELTA is determined by the report template DELTA used to generate the report. The number of decimals may be altered by editing the field in the report template that your method uses to generate it’s reports.

If you don’t specify a report in the method, DELTA will choose one of the default reports from it’s program directory. Chapter of the manual 10 details the mechanism DELTA uses to select a default report to use for a particular method. You may edit the default reports if you wish, however this practice is not recommended as installing a software update will overwrite your altered default methods.

The preferred technique is to use the report editor to load the default report that you determine DELTA has been using, make the desired alterations, then save this new report with a different name in the same directory that you will be running your method(s) from. You must then enter the report name in the Report Form field of the Run Settings section of any method you want to use the modified report.

If you want to override the default reports, the safest technique is to copy the default reports into the same directory as your methods then modify the reports there. Since DELTA always searches the method directory for the default report before searching the DELTA program directory the modified reports will be found first. If you use this technique you are safe from software updates, however you should check upon upgrading your software that the new version doesn’t provide new features that you aren’t taking advantage of.

The most common field altered for this reason is the result column of a report. To alter the decimals for this field in any of the default reports.

1. Open the report editor and load the report you want to alter.

2. Double click on the field (row of square dots) at the far right of the Loop body to open the field editor.

3. Once the field editor is open, check that the value being printed by this field is Result (of calculation). If it isn’t you probably double clicked on the same field, select Cancel to close then double click on the correct field.

4. Change the Decimals field to indicate the desired number of decimals. DON’T alter anything else unless you really know what you are doing. Select OK to accept the changes and close the field editor dialog.

5. Save the report and close the report editor.

If you require more detail on report templates refer to the manual chapter 10...CREATING & EDITING REPORT TEMPLATES.

Stripcharts are plotted according to the Stripchart Parameters settings in the method used to generate the report. To alter stripchart geometry or other characteristics use the following steps ...

1. Open the method editor.

2. If necessary, (if the method isn’t already loaded into the method editor) load the method.

3. Select the Stripchart Settings button to open the stripchart settings editor.

4. The settings in the Chart Size and Positioning group determine the stripchart geometry. If printing in portrait mode alter the Depth setting to alter the depth of the plot down the page (up to 16 pages). To alter the position of the left and right edges of the alter the Left Edge and Right Edge settings. For help on the other settings press F1 for on line help.

5. To test your new stripchart settings using the method editor working chromatogram select Test. The working chromatogram will be plotted using your current settings.

6. Once satisfied with the result, select OK to accept the new settings then save the method.

7. Process a chromatogram using Run...(whatever you have been using) to test your results.

This is usually required when you wish to re-process a sample run from file...you have to alter the chromatogram Source to File for the entire sample sequence so that chromatograms will be loaded from file instead of being captured.

The following procedure can be used to alter any field throughout an entire sample sequence. We will only explain alteration of the Source field.

1. Firstly open the sample sequence using either a sample sequence editor or the editor available from Run...Sequence.

2. Then double click on any line. An edit form will open, alter the Source field to whatever setting you want propagated throughout the entire sequence.

3. Select the All button adjacent to the Source field. A dialog box will open asking you to verify that you wish to set the Source field throughout the entire sequence, select OK. You will be returned to the edit form.

4. Select OK to close the edit form and return to the sample sequence, the entire Source column will now be set to your new setting.

To re-process a sample run you alter the Source setting to File for the entire sample sequence then perform a run in the usual fashion. This is desirable if you have made alterations to the method(s) involved in the run and you want to re-integrate and re-calculate everything. However you may have performed a sample run with Print Reports disabled and now you wish to simply re-print the reports already in the chromatograms.

To do this simply select Run...Sample Sequence (or whatever Run... technique you used to capture the data) then set up as if you are going to re-run and select the Review button instead of the Run button.

The Run... window will close and a chromatograms review list will open pre-filled with a list of all of the chromatograms which were collected by the run (in the order they were collected). To re-print the reports from ALL of the chromatograms click on Tag All to tag all of the chromatograms followed by Print to print all tagged chromatograms.

If you only wish to print the report from selected chromatograms you can click on each chromatogram you wish to print to toggle it’s tag, then click on Print to start printing.

For more information on reviewing chromatograms refer to the manual chapter 7...REVIEWING CHROMATOGRAMS & REPORTS.

Open the sample sequence using a sample sequence editor (Edit...Sample Sequence). Select File...List, select the target printer then select OK.

Using the method editor, open the method you wish to list. Select List or File...List. The List Method dialog box will open, tag the method sections you wish to list, select the target printer then select OK.

When runs are in progress the Run…Stop menu entry will be enabled. Selecting Run…Stop will cause a sub menu to open showing the control panels currently running. You can either click on the name of the control panel you wish to stop in the Run…Stop menu or …. Double click on the Run Status icon or select Status...Runs to open the Run Status window. In the Run Status window locate the control panel controlling the run you wish to abort. Select the Stop button on that control panel.

Any chromatograms currently being collected by the control panel will be discarded and the run will be terminated. If the Notify upon run complete preference is enabled an information box will open indicating that the run has completed. If an autosampler is being controlled the control panel won’t become available for new runs until all sample vials have been returned to the sample tray.

Open the interface status window and select the Stop button on the input channel recording the chromatogram to be truncated. Data collection on that chromatogram will terminate and the chromatogram will be passed to the report generator for normal processing.

DELTA can export results to special ascii text files which can then be imported into other packages such as LIMS, spreadsheets, data base, etc. for historical logging or statistical analysis.

To enable export for a method enable the Write Export Files option in the method’s Run Control settings page (look in the Report Options group).

When processing a chromatogram using such a method DELTA will generate export files, containing the results of the analysis, suitable for importing into other software packages (eg. spreadsheets). Export files have the same file name as the chromatogram they take data from, except that the file name extension is .PRN instead of .RAW. For example, an export file produced from a chromatogram named c:\delta\data\test.raw would be c:\delta\data\test.prn. The report template named __EXPORT.REP in the same directory as the DELTA programs is used to generate the export files. If alteration of the export file format is desired then the DELTA report editor may be used to edit __EXPORT.REP or a new __EXPORT.REP may be created in the same directory as the method (it will be found before the default __EXPORT.REP.

The .PRN file is an ascii comma delimited text file. This means that each line is terminated with a carriage return/linefeed pair, and that each field on each line is separated from the next by a comma. Additionally, string fields (eg. sample or component names) are surrounded by quotation marks. For example, if the three following fields :

1.2345 (numeric) COMPONENT-X (string) 5.6432 (numeric)

were output on the same line in the export file, the line would appear as follows :

1.2345,"COMPONENT-X",5.6432

With a carriage return/line feed at the end of the line. This export file format also has the advantage that it can be inspected using a standard text editor.

An example export file follows :

"SAMPLE ","11:41 am","30/ 5/96", 0,"SAMP","PERC ","AREA ","FILE",1, 1.000, 1.000

5, 1, 0,"Lauric acid ", 1.19,"VT", 134.17, 40.33, 0.79

6, 0, 0," ", 2.02,"BB", 5.43, 1.28, 0.03

7, 2, 0,"Myristic acid ", 2.60,"BB", 114.17, 19.47, 0.67

9, 3, 0,"Palmitic acid ", 5.45,"BB", 394.37, 57.07, 2.31

10, 0, 0," ", 6.27,"BV", 3.48, 0.67, 0.02

11, 4, 0,"Heptadecanoic acid ", 6.58,"VB", 2365.33, 391.30, 13.88

14, 5, 0,"Stearic acid ", 7.51,"BB", 485.26, 79.54, 2.85

15, 6, 0,"Oleic acid ", 7.66,"VT", 30.48, 7.78, 0.18

16, 7, 0,"Linoleic acid ", 8.07,"BB", 35.60, 6.20, 0.21

18, 8, 0,"Linolenic acid ", 8.53,"PP", 34.88, 2.73, 0.20

Note that numeric fields may have leading blanks and string fields may have training blanks. Excepting for these two characteristics the format may be controlled by altering the __EXPORT.REP report template.

The standard file format consists of a single header line followed by a line for each reported peak. If you wish to suppress the printing of lines for unidentified peaks you should either disable the Report Unidentified Peaks setting in the method Run Control settings or alter the loop within __EXPORT.REP. Unfortunately the latter option will affect exports from all methods.

The header fields contain the following information (string fields are quoted):

"SAMPLE NAME", "TIME","DATE", SAMPLE EC,"TYPE","CAL TYPE",

"CALC BASIS", "SOURCE", INJ#,AMOUNT,DILUTE

Where :

SAMPLE NAME Is the sample name taken from the sample sequence.

TIME Is the time at which the export file was generated.

DATE is the date the export file was generated in dd/mm/yy format.

SAMPLE EC Sample calculation error code( see ERROR CODES for details)

TYPE Is the Sample Type from the sample sequence. Valid values are SAMP, STD1, STD2, STD3, STD4, STD5, STD6, STD7, STD8, BLNE, or SUIT.

CAL TYPE Is the calculation type and may have one of the following values... PERC, NORM, INTSTD, EXTSTD, USER.

CALC BASIS Only useful for PERCENT or NORMALIZED calculation types. May be AREA or HEIGHT

SOURCE Is the chromatogram source taken fro the sample sequence line. This may have a value of ACQU or FILE.

INJ# This is the injection number, it has a range of zero to nine. A value of zero indicates that the calculation is for an average of a number of injections.

AMOUNT The Amount figure from the sample sequence line.

DILUTE The Dilute figure from the sample sequence line.

This is followed by a line for each reported peak, each of these lines has the following form :

PK#,CPT#,CPT EC,"CPT NAME",RT TIME,BLNE TYPE,AREA,HEIGHT,RESULT

where :

PK# is the component peak number (0 = no peak)

CPT# is the component number (0 = no component)

CPT EC is the component error code (see ERROR CODES)

CPT NAME is the component name (all blanks for unidentified peak)

RT TIME is the peak retention time

BLNE is the baseline separation type for this peak

AREA is the peak area

HEIGHT is the peak height

RESULT is the peak area percent, height percent, concentration depending upon the method calculation settings.

Note that a peak number of zero in a line that commotions a component (component number is not zero) indicates that a peak was not found to match the component. A component number of zero indicates that a peak for which no matching component was found. Neither case necessarily indicates an error condition.

As well as the standard report which is generated at the completion of a chromatogram acquire, DELTA can also create a Microsoft Excel compatible spreadsheet at the same time. The name of the spreadsheet is the same as the name of the chromatogram with the exception of the file extension which becomes .XLS. To generate a spreadsheet, you must perform at least two steps.

The resultant spreadsheets can be inspected using either DELTA's inbuilt spreadsheet or Microsoft Excel. Note that if you save spreadsheets with Excel you may not be able subsequently open them using DELTA's inbuilt spreadsheet.

Step 1 - Enable spreadsheet generation

Edit the method you wish to use to capture the chromatogram.

Go into Edit... Method...Run Control, then cross the Write Spreadsheets option and enter a report template name in the Report Form field (if you aren't already using a custom report, make up a name and create the report in step 2 below) . Press OK to close the Run Control window, and then save and close the method.

Step 2 - Enable Spreadsheet Cells in the Report Template

Edit the report that is used with the method.

Note that if you have not specified a unique report name in Edit... Method...Run Control, then DELTA will use a default report. It is unwise to alter a default report. Instead, open the default report (see chapter 12 in the Delta manual to determine what the default report would be for your method), save the report with a unique filename, in the same directory as the method; then specify this report file name in Edit... Method...Run Control.

Double click on each field in the report that you wish to export to the spreadsheet, then cross Spreadsheet and enter spreadsheet the column and row where the result should go. Note that row numbers for cells within a report loop are used to determine the position of the cells produced by the first row of the loop; row numbers for the same cells in subsequent rows generated by the loop are incremented by one.

You can 'bury' a result in the report which will appear in the spreadsheet and not in the report. Do this by uncrossing Report, then crossing Spreadsheet and entering the column and row.

Lastly save and close the report

Now when ever you run that method and process a chromatogram, a spreadsheet with same file name as the chromatogram but with an extension of .xls will be generated. It will containing the results corresponding to selections made in the report template used by the method.

Step 3 - Spreadsheet Templates

If you would like to provide custom column headings etc, you may also use DELTA's inbuilt spreadsheet editor to create and save a spreadsheet template. Save the template in the same directory as the method that uses it. Then specify the name of the spreadsheet template (excluding the .XLS extension) in Edit...Method...Run Control...Spreadsheet Form. Now this template sheet is used instead of a blank sheet when Delta creates a spreadsheet using this method.

There are some chromatography applications where the average of a number of calibrations performed throughout a sample run must be used to form a calibration curve for calculating the sample results.

Performing this requires a two pass process. Typically on the first pass the chromatograms are captured and the cumulating average of the standards built. On the second pass the standards are eliminated from the sample sequence and the carry over calibration that remains in the method from the first pass is used to calculate and report the results for the samples.

Of course, to be using standards you must be using a method calculation setting that supports calibration (eg. external or internal standards). This procedure assumes that the method is already set up for calibration (calculation type set, standard concentrations entered, etc.)The following steps will give the desired result.

1. In the method Calculation Settings set Update Calibrations by to Running Average and save the method.

2. Prepare your sample sequence then prior to running the sequence in Run...Sample Sequence ensure that the Run Time Option titled Reset Calibration is enabled. This will ensure that the calibrations in the method are cleared prior to the first pass.

3. Run your sample sequence. This will cause a running average of the calibrations to build up in the method during the sample run.

4. After the sample sequence has completed, return to Run...Sample Sequence, DISABLE the Reset Calibration run time option so the existing calibration in the method will carry over.

5. Remove the STDx lines from the sample sequence so that no extra re-calibrations will occur.

6. Open any sample sequence line (double click on it). Set the Source to File, then click on the All button beside the Source field to set the entire source column to File. OK the query to Global Change then select OK on the sample form to close it. All Source entries are now set to File.

7. Run the sequence again, all of the samples will be processed using the calibration which was formed using the average of the standards over the run.

This technique can accommodate up to 255 averages for each standard.

Chromatogram reports are produced and embedded within a chromatogram when the chromatogram is processed by a sample run. If the Plot Chromatograms option is disabled when the report is generated then the request to plot the stripchart doesn’t get embedded in the report. This means that whenever you re-print the report you will get the same result...no stripchart plot.

To place a chromatogram plot in a chromatogram report the chromatogram must be re-processed in a run with Plot Chromatograms enabled. The Integrate only if necessary run time option may be enabled if you wish to save re-processing time by skipping the re-integration of chromatograms.

Integrating the chromatogram on screen alters the chromatogram peak table, it doesn’t automatically cause the report to be re-generated. Refer to section 17.1 for more detail on chromatogram reports.

Manually integrating the chromatogram alters the chromatogram peak table, it doesn’t automatically cause the report to be re-generated. Refer to section 17.1 for more detail on chromatogram reports.

In the method editor, open the method’s component table; then double click on the offending component table entry to open the component editor form. Now make sure the Calculate option is NOT enabled. If it is then this is what is called a Calculated Component. Calculated components are NOT used to identify peaks, they are merely a table entry that holds a name and an equation that is evaluated when a chromatogram is processed in order to derive a result.

The suitability report suppresses results for columns that require information that was not supplied, for example a unretained solvent or the column length.

You must re-process the chromatograms to affect the reports, refer to section 17.1 for more detail on chromatogram reports.