The CODAC group has published a new version of the Plant Control Design Handbook after a thorough review involving all ITER Members. This document defines standards, specifications and interfaces applicable to all ITER plant systems. In total 161 plant systems have been identified in ITER; the cooling water system is one, for example, as is the vacuum vessel. Diagnostics alone comprise 89 plant systems.
The new handbook specifies the development process, with clearly defined deliverables, quality assurance requirements and milestones, as well as catalogues of standard software and hardware components. These standards are essential in order to integrate all plant systems into the central ITER control system, to maintain all plant systems after delivery and to contain cost by economy of scale, both for spare parts and in human expertise. The Plant Control Design Handbook will be enhanced and released at regular intervals throughout the construction phase of ITER.
In addition, the CODAC group has executed a standardization process, endorsed by the ITER Organization and the seven Members, to minimize the number of brands of Programmable Logic Controllers (PLC). The process has been completed with the selection of Siemens Simatic S7. PLCs are widely used in industrial automation and will also be widely used at ITER. Unlike a general purpose desktop computer a PLC is designed for harsh environments, extensive input and output arrangements and predictable real-time performance. It is estimated that for ITER, hundreds of thousands of actuators and sensors will be interfaced to many hundreds of PLCs. return to Newsline #81