Drives and Controls Magazine
Safe position measurement system is certified to SIL 3
Published:  14 June, 2012

SEW-Eurodrive has collaborated with Hima and Pepperl+Fuchs to produce a position measurement system that has been certified by TÜV Rheinland for use up to SIL 3/PLe. The system consists of a P+F PCV data matrix-based position measuring system, Hima’s HiMatrix or HiMax safety controllers, and certified function blocks and drive components.

The TÜV-certified function blocks are designed for applications requiring a safe position, velocity, acceleration and deceleration control. They simplify programming and allow the processing of one or more axes, as well as calculations in different co-ordinate systems. Other advantages are said to include easy handling and reduced documentation costs.
The safe distance measurement system is based on P+F’s PCV system which reads square data matrix codes from a printed code strip. Each code is unique, thus providing absolute position information.
The system allows dynamic modification of safety zones, position limits, maximum speeds and other parameters, depending on the operating mode and other conditions.
One potential application for the new system is on overhead conveyors where it could be used to monitor speeds, safe distances and direction. Other possible applications include the safe acceleration of cranes, hoists, mine conveyors and bucket loaders.