PLCs and HMI software are becoming more advanced every day, but there are still many things that require a more powerful approach than ladder logic. Some of these applications can be handled with a BASIC or C coprocessing module, running in parallel with a PLC. Examples of this type of system created by ChronoLogix include programs to solve stock cutting optimization problems, and programs to communicate with a large network of scales (including priority scheduling for better performance on slow data networks). Additionally, most modern PC based HMI software has the ability to run macros or VB scripts that can handle semi-complex tasks.
When the traditional methods fall short, we turn to Visual Basic or C++ to program solutions. Using these tools, almost anything imaginable can be done. Complex process optimizations, database queries, automated report generation, and 2 way communication with other devices like scales, barcode equipment, and product labeling systems- all these things and more are possible.
An example of multiple concepts written in Visual Basic for Hussey Seating Company is depicted in the image to the right. This is a stand alone program, a complete HMI software replacement. It accesses an order management system, gets order information and queries an Access database for detailed part dimension and description data. It then sorts all parts to be done by size and communicates with an existing PLC to run a machine press. At the same time it communicates with a videojet printer to print descriptive data on parts as they exit the press.
ActiveX Controls
Sometimes a more seamless integration with an existing HMI is required in an application. HMI systems like RSView and Cimplicity, or even a web browser like Internet Explorer can contain ActiveX controls on their screens. An ActiveX control is a program that embeds itself on an HMI screen, it can interface with the PC as well as the HMI software's tag database. This allows the HMI to perform tasks normally well beyond it's capabilities. Examples of ActiveX controls are shown in the three pictures to the right. These would normally be surrounded by other HMI elements but have been reduced to show only the controls themselves.
The first was developed for Kalwall, it uses RSView to handle manual machine operations. The control takes data from their order management system and optimizes part cutting in real time based on stock type, length, and angle matching algorithms to ensure the best possible use of material. It also logs all machine output for business planning and accounting purposes.
The last two ActiveX controls were developed for a Kraft Foods facility to use on all of their process cheese lines. They interface with RSView as well, the first one handles recipe management- load and save, create, edit and run recipes. It also implements security to prevent unauthorized changes to recipe parameters. The second control accesses RSView data logs and displays cook data for a selected date and time range in a preview window. This data can then be printed for permanent records. The print process is also automated to print reports at the end of each work shift.
Our Edge is Your Edge
ChronoLogix is dedicated to working with you in order to create the most powerful and flexible systems possible. ActiveX controls and custom PC software allow us to achieve goals that other systems integrators cannot, and in turn give you an intelligent advantage over your competition.
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