Harting's PowerSwitch decentralised motor controller forms the heart of an AS-i based Fieldbus control package adopted by EWAB Engineering for an innovative conveyor system. EWAB Engineering AB, a Swedish company with subsidiaries in the USA and numerous European countries, manufactures a patented industrial palletised conveyor system that has found widespread acceptance for handling components and subassemblies between different machining and assembly operations. EWAB is a market leader among suppliers to the automotive industry.

The flexible modular highway and satellite design of the conveyor system is a perfect application for control via fieldbus.

After careful consideration, EWAB adopted the AS-i bus as a standard solution, and went through the process of selecting the AS-i products they required to provide a fully functional system.

During this selection process, they recognised the benefits of decentralising the motor control by means of AS-i compatible enclosed motor starters located directly adjacent to each motor.

EWAB investigated a number of alternatives and were introduced to Harting PowerSwitch while visiting the Harting stand at the 1998 Fieldcomms Exhibition.

Following meetings between Harting and EWAB, a first prototype was produced for testing purposes, and met their requirements exactly.

At the same time, EWAB was successful in winning a contract to supply the Ford Motor Company with conveyor systems for the crank and cam production lines (inline 4- and 5-cylinder engines) in Dearborn, USA, and Chihuahua, Mexico.

Owing to the size of the project, manufacturing has been shared between the EWAB facilities in Sweden, USA and the UK.

When the contract was placed, the Ford Motor Company specified that all enclosures housing electrical equipment were to be of metal construction and, furthermore, that all electrical switchgear was to be supplied by Telemecanique.

The rugged construction of PowerSwitch complied fully with the first part of the specification, but the standard internal electrical switchgear was from a different manufacturer than the one specified.

Following a request by EWAB, Harting developed a customised variant that met all the Ford Motor Company's requirements.

After successful demonstration of a prototype, Ford immediately gave its approval.

EWAB are currently implementing systems at both Ford locations with 290 PowerSwitch units for motor control.

Harting'S PowerSwitch is now an approved device in EWAB's standard AS-i system worldwide.

Further AS-i projects will follow in the near future, and PowerSwitch will be an integral part of each system.