Tuesday, August 25, 2009

Scheduling the printing of an Excel file which has an add-in from the command line using visual basic scripting (vbs) via wscript

On a recent project I was required to print out an Excel based report which made extensive use of OSIsoft PI DataLink's Excel Add-in on a sechduled basis (7am daily).

Unfortunately Excel does not easily allow for the printing of an Excel file via the command line via switches or parameters when calling Excel.exe (e.g. C:\Windows\MS Office\Excel.exe -print "C:\Reports\My Report.xls").

I was able to find examples on the Internet which made use of cscript or wscript where one calls VBS code, and where one provides the file name as argument, for example:

wscript "C:\Data\My Scripts\printXLS.vbs" "C:\Data\My Reports\Daily Analyser Excursion Report.xls"

Note the convention of using "" around full path filenames as they contain spaces.

The file printXLS.vbs would contain something akin to the following code:
Dim XLApp
Dim XLWkbk
Dim ObjArgs

set ObjArgs = wscript.arguments
if ObjArgs.count <> 1 then
wscript.echo "Invalid passed arguments"
wscript.quit
end if

Set XLApp = CreateObject("Excel.Application")
XLApp.Visible = False

Set XLWkbk = XLApp.Workbooks.Open(objargs(0))
XLWkbk.PrintOut
XLWkbk.Close False

XLApp.Quit

Set XLWkbk = Nothing
Set XLApp = Nothing
Set ObjArgs = nothing
The problem I experienced was Excel Add-ins are not automatically loaded in Excel applications created via Automation. This resulted in the Excel file printing but with OSIsoft PI DataLink Excel Add-in functions not being recognised and #NAME! appearing in the relevant cells on my printout.

The solution I found was to explicitly load the Excel Add-in via XLApp.RegisterXLL ("fullpath filename")

So my VBS file looked like something this:
Dim XLApp
Dim XLWkbk

Set XLApp= CreateObject("excel.application")

XLApp.Visible = FalseSet XLWkbk = XLApp.Workbooks.Open("C:\OSIsoft\Reports\Scheduled\PI Report - Analyzers - Quality Excursions.xls")
XLApp.RegisterXLL ("C:\Program Files\PIPC\Excel\pipc32.xll")

XLWkbk.Worksheets("Report").Calculate
XLWkbk.PrintOut
XLWkbk.Close False

XLApp.Quit

Set XLWkbk = Nothing
Set XLApp = Nothing
I also wanted to be able to specify the number of copies to print and which printer should be used namely PRC2 in my case. If the printer is not specified then the windows default printer is used.

I also decided to allow one to specify the Excel workbook and which specific worksheet in the Excel workbook to be printed.

So allowing for parameters the VBS look something like this:

'Arguments'1 Excel Name e.g. "C:\OSIsoft\Reports\Scheduled\PI Report - Analyzers - Quality Excursions.xls"'
2 Worksheet Name e.g. "Report"'
3 Printer Name e.g. "PRC2"'
4 No of copies e.g. 1
Dim XLApp
Dim XLWkbk
Dim ObjArgs
Dim strFileName
Dim strWorkSheetName
Dim strPrinter
Dim intCopies

Set ObjArgs = wscript.arguments
If objArgs.count <> 4 Then
wscript.echo "Invalid Passed Arguments"
wscript.quit
End If

strFileName = objargs(0)
strWorkSheetName = objargs(1)
strPrinter = objargs(2)
intCopies = objargs(3)

Set XLApp= CreateObject("Excel.Application")
XLApp.Visible = False
Set XLWkbk = XLApp.Workbooks.Open(strFileName)
XLApp.RegisterXLL ("C:\Program Files\PIPC\Excel\pipc32.xll")
XLWkbk.Worksheets(strWorkSheetName).Calculate
XLWkbk.PrintOut , , intCopies, , strPrinter
XLWkbk.Close False
XLApp.Quit

Set XLWkbk = Nothing
Set XLApp = Nothing
Set ObjArgs = Nothing
I was then able to use Windows Task Scheduler to call the VBS file to print my Excel files on a daily basis.

Tuesday, August 11, 2009

Handling Late Data

Handling "Late Data" into a historian can be tricky when that data changes over time.

For example, we have a situation where material arrives in a truck on a weighbridge for processing. A sample is taken and sent to a laboratory for composition analysis but in order that the process can continue without waiting for the lab results, estimates are made and stored in the historian for temporary use.

After some time, once analysis has taken place, the actual values then replace the initial values (and the temporary historian entries for that timestamp must be updated) so that more accurate calculations on the given data can be performed.

This back-tracking and synchronisation of historical data and more have been incorporated into our IDX Listener technology to allow for efficient handling of these 'late data' into a historian.

Late Data Presentation Image

Monday, August 3, 2009

Profibus PA for Hazardous Areas

Presentation and Paper by Michael Bean on the use of Profibus PA for Hazardous applications.

Profibus PA was designed as a solution for automation in Process Applications where it is often necessary to guarantee levels of safety with regard to potentially explosive atmospheres. In this paper and presentation given at the Hazardous Areas Conference held at Gallagher Estate in 2008 I discuss Profibus PA's applicability to such applications.

The presentation raised quite a bit of interest as various parties debated their companies' acceptance of the FISCO. Many were surprised at the advantages offered by the "high-powered trunk" concept.

Profibus Diagnostics

I often have people asking for a copy of my slides from a Profibus Diagnostics Seminar that we gave at the Eskom convention centre last year. I got the last slot of the day so I ended up speaking to only 40 people or so.

If you missed it you can have a look at the slides here.