The European market for operator interfaces with built-in PLC functions will expand at a CAGR of 11.1% over the coming four years, to reach €64.5m by 2010. The prediction, in a new study from the market analyst IMS, means that sales of these devices will grow faster than the HMI market as a whole.

Sales of the integrated devices are being driven by the availability of increasing numbers of these products, a greater awareness among users of their capabilities, and the trend towards decentralised control, with the embedding of PLC functions in HMIs allowing the workload on central controllers to be cut.

"The process of combining an operator interface and a PLC into a single unit may be considered less alien to users than embedding PLC functionality into other automation products," remarks the report`s author, IMS senior analyst, Tim Dawson. "PLCs and operator interfaces have always traditionally worked very closely together, both location-wise and as part of a control system."

IMS`s predictions are backed by a survey of automation specifiers and buyers which reveals that most are aware of the combined products and more than two-thirds have either already bought products with embedded PLCs — or plan to do so within three years.