The Data Acquisition System (DAS) for the Improved CERN SC

Abstract

A digital data acquisition system (DAS) based on a minicomputer is described which registers the failure sequences in various equipment areas of the CERN synchrocyclotron (henceforward referred to as the SC). The avalanches of failure signals which occur from time to time are tapped from the alarm/ security systems, time-resolved to 10 msec and recorded on a printer in order to aid SC failure diagnosis. The mechanisms of the DAS and its relation to the SC equipment are explained in some detail. All programs were constructed at assembler language level for speed and for ease of on-line program maintenance. The alarm sequences recorded have been of considerable help during the running in of the new radiofrequency system. Now that the new SC is operational, the DAS furnishes useful data from several equipment areas to the operators and engineers. IntroductionIt was felt that a better understanding of the series of events occurring upon SC failures than could be obtained with visual failure indicators was necessary in order to decrease the time taken in machine fault-tracing. Some failures happened mysteriously and the sequences of alarms occurring needed to be analysed so as to find the likely source of trouble and get the SC running again as soon as possible.