Process Control by Distributed Intelligenc

Process control by distributed intelligence, commonly known as distributed and hierarchical control, has developed over the last few years as a natural outcome of the need to separate control functions by Process Area and Level of Control, while maintaining overall system security and simplicity of operation. This paper describes its evolution and illustrates its implementation in the cement industry with the latest available control modules. Various aspects related to the issues of system flexibility, improved alarm handling, increased trending capability, features of the CRT-based display as an operator interface, system redundancy, and ease of operation are addressed.