ITO Hiroki1 KATO Makiko1 TORIGOE Kenji1 TOMO Tetsuya1
We have developed Standard Batch Report Package for CENTUM CS. This package is a useful report function for batch process which has an open interface. This papaer describes the concept, functions and effectiveness of this package.
CENTUM is a registered trademark of Yokogawa Electric Corporation.
- DCS Center, Process Control Equipment Division
Report functions in process control are often positioned as part of the logger functions. However, plant operation data in a batch process should be not only logged regularly but also acquired and managed for each batch execution. The report function for logging plant operations in a batch process mainly comprises a function to print out plant operation data collected for each batch execution, and there are various approaches available to implement this function. As a key point in its implementation, it is necessary to take into account the various popular document creation software programs that run on personal computers (PCs). Such programs have inexpensive, advanced document output functions, and it is important to make the best use of them. Our Standard Batch Report Package is a report function developed in consideration of this aspect.
The developmental concepts of this package are as follows.
- To have a report function suited to batch processes that:
- improves compatibility with CS Batch*2
- separates the report function from the logger function
- To implement an open architecture that:
- enables users to take full advantage of PC software
- supports all CENTUM CS-specific data formats
- expands the types of data that can be handled
- To provide the most often used functions in an easy-to-use form
Figure 1 Structure of the Standard Batch Report Package
Employing the aforementioned concepts, this package for the CENTUM CS has been structured as shown in Figure 1.
- In a distributed control system (DCS):
- the engineering workstation (EWS) is an engineering function;
- the information and command station (ICS) is an operation and monitoring function; and
- the field control station (FCS) is a control function.
- The builder function:
1) defines batch report formats using a spreadsheet method
2) creates the defined batch report format as a formatter
3) loads the formatter to the print-out function
- The print-out function:
4) accepts a command to start batch report printing
5) refers to the batch report format from the formatter
6) acquires data
7) forms a print image and outputs it to the printer
Figure 2 Open Link Interface
8) reads batch report definitions
9) outputs batch reports
3. Open Architecture
Figure 2 shows the structure of the open link interface of the standard batch report function. The interface covers the following:
- Acquired data
Data acquired by the print-out function are saved in a file format independent of the format of the CENTUM CS and can be accessed by other software. In this way, data can be read into increasingly popular personal computers and a more advanced report function can be constructed. For the implementation of an open architecture, it is important for this package to support all CENTUM CS-specific acquired data. The types of data that can be acquired, therefore, have been greatly increased.
- Reading of batch report definitions
The package can read batch report definitions created with other software. (For example, a CSV format file*3 created with Microsoft Excel*4 can be read.) An instruction to acquire data can be given when defining a batch report simply by entering in a character string the logical name (tag name, etc.) of necessary data. In this way, batch report management can be easily carried out away from the CENTUM CS.
Table 1 Types of Printed Data Items
|Classification||Printed data||Classification||Printed data|
|Constant||Character||CS Batch Common block data||Common block data|
|Numeric string||Common block comment|
|Process data||process data||Common block item comment|
|Tag comment||Common block engineering unit|
|Tag item comment||CS Batch recipe header||Created item|
|Tag engineering unit||Recipe name|
|Alarm/Event||Batch journal||Recipe comment|
|Historical data||Trend data||Product name|
|Calculated value||Arithmetic expression||Author|
|Cell data||Security level|
|Time value||Printing time||Recipe description|
1. Printed Data
|Figure 3 Structure of a Batch Report|
Table 1 lists data items which can be printed in a batch report. A simple character string can be used to instruct the program to collect each data item found in the batch report definition so that, even when a batch report is defined by another software program via the open link interface, data can still be acquired easily.
2. Configuration of Batch Report
As shown in Figure 3, batch reports supported by this package comprise two parts having different formats. One is where the batch report format is in spreadsheet form and the other is where the format is free. A spreadsheet divides a sheet of paper into blocks called cells where data are distributed, thereby presenting a print format for an entire batch report. Spreadsheets are effective when the number and the format of data items can be decided beforehand.
The free-format portion is used when the number and the format of data items cannot be determined beforehand, as in the case of an alarm event. In addition, the following functions are available to make more advanced batch reports.
- Addition of headers and/or footers
- Addition of grid lines
- Separation of the spreadsheet into pages
Figure 4 shows an example of a printed batch report created with this package.
|Figure 4 Example of a Printed Batch Report|
3. Format of Printed Data
The format of the data to be printed in each cell can be designated in detail by the position of the data in a cell, the number of digits, and the position of the decimal point. However, if the printed data are for plant operations, it is general practice for the format to be designated separately during the engineering operation due to the display format for the operation and monitoring function. Therefore, it is troublesome to designate the format again at the time of batch report definition. This package has a function for deciding the format according to the display format defined beforehand in the plant operation data.
4. Builder Function
The objective of the builder function is to create a file called a formatter that defines the printed data and format of a batch report and loads it to the print-out function.
- Man-machine interface
A formatter is created by defining the printed data and format in each cell in a spreadsheet. Figure 5 shows a formatter creation screen.
- Open link interface
The open link interface can read a text file described in a fixed format and define a formatter. By doing this, the batch report definition created by the text editor or another batch report creation program can be read into this package. The text file is in the widely used CSV format.
- Preview function
There is a preview function provided to check the defined formatter print image on a builder-function screen. Since data acquisition is not carried out, plant operation data are considered to be provisional. However, the preview function is very effective in checking the print format.
Table 2 Batch Report Print Startup Methods
|Auto||CS Batch recipe end|
|CS Batch unit recipe end|
|Manual||CS Batch operation|
|Event driven||Sequence massage|
5. Print-out function
|Figure 5 Formatter Creation Screen|
The print-out function collects data, forms a print image, and outputs it to the printer according to the formatter file created by the builder function.
- Print start
Manual starts, automatic starts, and event-driven starts are available. Table 2 lists the startup methods.
- Open link interface
The open link interface can save the printed result of a batch report as a text file. Furthermore, an external software tool can access the text file at the same time as it is output to a printer.
- Debug function
The debug function allows necessary batch reports to be printed with a command at any desired time. In this way, only a printed batch report is debugged beforehand. Furthermore, the debug function retains error information on data acquisition and other items as a text file.
In this paper, we described the concepts, functions, and effectiveness of the report function in a batch process. On the basis of the concepts of the package as a report function, development will proceed according to user needs which will become more diversified in the future.
- Sakamoto, H. and T. Kano. SP88 and CS Batch. Yokogawa Technical Report No. 21 (1996), pp. 1 to 4.
- Terashima, N. Management Information Functions of CENTUM CS. Yokogawa Technical Report No. 21 (1996), pp. 23 to 26.
*2 Batch control package in CENTUM CS
*3 CSV is an abbreviation for Comma Separated Values, meaning the text format in which data are delimited by a comma.
*4 A registered trademark of Microsoft Corporation, USA.