How components react and interact in a network, qqqand the ease in which a user can gain access to qqqthe process, is vital to the smooth-running of any qqqform of production. Dirk Hartmann reports.

Communication is the most important aspect in a network. An ideal control is achieved in production when communication is guaranteed from the lowest level to the higher control level up to the top management level.
In other words, the production's output can be read or changed by the user, as well as by the shift manager in the control room.
For this purpose you need intelligent and flexible components on each communication level. The actor/sensor-level has to be equipped with light curtain, switches and other fieldbus capabable components.

Digital data

The upper programmable logic controller (PLC) processes this data. A visualisation-system is needed
at the control level which handles digital data, as well
as analogue data from a PLC via the bus-system.
This system also has to process and display this data beside a perfect data processing to the higher control level.
Pro-face has made this 'system' a reality with its product range GP-2000. Developing this operator panel, the company has focused on communication.
The panels are distinguished by a vast number of serial interfaces and with them they can get in contact with the outside world.
All graphic-panels have a resistive touch surface which comes up to industrial demands. They are available as 7.4, 10.4 and 12.1in display size.
The TFT displays with 256 colours guarantee a high quality beside an optimum viewing angle. Because of the built-in Ethernet connection they can also be used as operator panels for machine operation.

Built-in serial interface

The local PLC is connected by the built-in serial interface. More than 150 different PLC-protocols guarantee unproblematic data transfer with the most current control systems.
The connection to a parallel printer can be realised through the built-in Centronics-interface. The second serial interface to connect a two-dimensional bar code reader.
With an integrated AUX-interface the panels of the GP-2000-series are connected to an external speaker to make warning signals or other critical conditions of machines heard.
The necessary sound-files in WAV-format can be filed safety in the integrated compact flash card.
As an extension there are several fieldbus modules available which can be mounted at the back of the panel. It is often necessary to show the user live-pictures of a production-line such as in quality controls or for the surveillance of a conveyor belt.
It is possible to show up to four CCD-video or RGB-signals at the same time by means of a multimedia unit. And there is no need for separate monitors.
The pictures are directly integrated into the operator interface. Each picture can be enlarged, made smaller or can be frozen as a still frame by a simple touch at the panel.

Quick access

Pro-face offers a project-tool which brings the user to the chosen control environment so that the wide operational range can be accessed quickly and effectively. The software-package GP-PRO/PBIII can be used with standard PCs operating Windows 95/98/NT.
Graphics production can be reduced into a minimum thanks to design libraries containing more than 1800 graphical icons.
In addition, files in DXF and BMP formats can be adopted from existing projects without any problems. The user can save most of the used elements in his own libraries for future applications. It is also possible to open different projects simultaneously and to move graphic elements by drag and drop with the help of the multi window function.

Internal programming

An additional highlight is the internal programming language D-Script where extended functions, such as password-programming, screen saver, calling of temporary input elements, automatic picture change and alarm merge administration, can be carried.
Existing projects carried out with earlier GP-PRO versions can be adopted. The completed application can be transmitted afterwards into the failsafe Flash-EPROM memory of the GP-2000 series. The optional compact flash card can also be used as an additional project or recipe memory.
It is not only the communication within a network that is important but also the maintenance remote control via internet.
Pro-face makes it possible as the first company world-wide to achieve a precise graphic of the user data from a stationery operator panel on any Internet-PC. A process picture, visible to the user, can be accessed simultaneously world-wide.
The cause of the problem is pinpointed within the process and eliminated which helps cut back on maintenance costs.
Pro-face has been providing solutions in operating and monitoring for a number of years. The company is also working on improving communication between man and machine.

ENQUIRY No 47

Dirk Hartmann is with Pro-face Deutschland GmbH, Stuggart, Germany. www.pro-face.de