Operational protocols for controlling accelerator equipment

The equipment used to operate an accelerator is varied. However, the different devices may be divided into a limited number of classes for which operational protocols can be defined. Operational protocols permit: (i) a uniform operation, (ii) a clear definition of responsibility between the various specialists, (iii) independent development of programs and use of the most appropriate technology, (iv) the change of hardware and the transportability of software, and (v) the fabrication of devices by industry for general use. An operational protocol should be independent of any given control system and it must not be confused with a transmission protocol. As a first step, one defines an operational model of the device to be controlled. The model must represent a high-level description of the device as seen by the user. It will be characterized by a set of parameters and a set of rules. Although the particular requirements of specialists are not included in the operational protocol, allowances should be made for them. Emphasis will be placed on studies carried out on power converters and beam instrumentation. A general-purpose control message architecture is reported. (orig.)