In the recent decades, the market for the products of the industrial process industries has changed greatly. The manufacture of mass products has shifted to locations where raw materials are available economically. Competitive pressures have forced a swing to specialization as well as to an ability to adapt to customers desires. The systems are designed so that the economic data, such as raw material properties, raw material costs, batch sizes, are quickly integrated into the processes. An important consideration is the assurance and improvement of product quality.
The operation of such systems requires a high degree of automation. With the assistance of process technology the control of the procedures can be optimized and personnel requirements minimized. The process control technology assures that process cycles are documented so that the quality of the product is always traceable.
The most important prerequisite for automation is knowledge of the actual process parameters, which can be ascertained utilizing measurement instruments. If the actions dependent on the measurements are to be realized then the specifications must naturally be qualitatively high. Therefore, the measurement instrument requires: