PC-based control pays dividends for Milliken

Edited by the Engineeringtalk editorial team Aug 22, 2002

Quality and value are among the key reasons why leading international textile and chemical manufacturer, Milliken, has chosen a PC-based control system from Hayes Control Systems.

Quality and value are among the key reasons why leading international textile and chemical manufacturer, Milliken, has chosen a PC-based control system from Hayes Control Systems for the new rubber calendaring installation at its Manchester site.

Key components of the control system are an industrial PC running TwinCAT real-time control software in conjunction with Windows NT, a 15in colour display with custom pushbutton station, five Profibus I/O nodes, and three variable speed drives controlled via the Profibus system.

All items, except for the drives, were manufactured by Beckhoff in Germany, and supplied by Hayes Control Systems, the sole UK agent for Beckhoff products.

"When we were working on the design of this project, we looked at several alternative types of control system", said Jeff Howard, chief engineer at Milliken's Manchester site, "including systems based on traditional hardware PLCs.

None, however, came close to matching the Hayes offer, in terms of quality and value for money.

Other deciding factors were the modularity and expandability of a system designed around the Beckhoff products from Hayes".

TwinCAT, the software suite at the heart of the Milliken system, converts virtually any modern PC into a real-time industrial control system comprising one or more soft (or virtual) programmable controllers (PLCs), together with sophisticated numerical control functions, a convenient IEC61131-3 compliant programming environment, and a versatile system manager.

Benefits of this approach include the use of readily available standard hardware, which offers unbeatable value for money; the ability to take full advantage of the latest developments in PC technology; a minimum number of components for a comprehensive control solution, and an exceptionally high level of system reliability.

In the Milliken application, TwinCAT is complemented by a Beckhoff industrial PC which, although assembled from cost-effective standard components, is specifically designed to withstand the rigours of shop-floor use.

Input/output facilities are provided by Beckhoff protocol-independent fieldbus modules and terminals which, in this case, are configured to use Profibus.

An efficient and attractive operator interface is offered by the 15in TFT colour liquid crystal display panel, which features a touch-screen, and is used in conjunction with a customised pushbutton station.

"The support services provided by Hayes during the design phase were excellent", said Howard, "the Hayes support engineers are experts at getting the best from the IEC61131 programming system, and were able to provide invaluable assistance to our own programmers by writing custom function blocks.

An added bonus was that the whole process was conducted via e-mail".

Milliken's engineers also found that the installation and commissioning of the new control system ran very smoothly, despite some initial unfamiliarity with the TwinCAT soft PLC software suite.

Milliken is very happy with the operation and reliability of the new control system, and is fully confident that the use of TwinCAT and other products from Hayes Control Systems was very much the right choice.

The company is now using similar equipment from Hayes for other projects on multiple sites.