The Technical Data Server for the Control of 100'000

THE TECHNICAL DATA SERVER FOR THE CONTROL OF100000 POINTS OF THE TECHNICAL INFRASTRUCTURE AT CERN

P.Ninin,eger,S.Lechner,R.Martini,D.Sarjantson,P.Sollander and A.Swift

CERN,Geneva,Switzerland

Abstract

We have defined a Technical Data Server(TDS)to be used for the supervision and control of the technical infras-tructure of CERN by its dedicated control room,the Technical Control Room(TCR),and by equipment groups.The TDS is basically a real-time information system which contains all states of the technical infrastructure:100000points describing electrical distribution,cooling water,air-conditioning,vacuum,safety,and similar systems.It is expected that the TDS will substantially increase system performance and ease operation.As the concept of such a data server is also of interest to other groups in CERN accelerator and experimental physics divisions,detailed software and user require-ments,as well as criteria for selection,implementation and maintenance have been elaborated in common with these groups.The project adheres fully to the European Space Agency(ESA)PSS-05Software Engineering Standards and its life-cycle approach.This paper describes the data acquisition and distribution mechanisms,the interfaces to equipment and to existing alarm and data logging systems and to operator supervision consoles,the alarm reduction mechanism,and the error-handling and logging.Problems encountered during the project development are discussed in some detail.

I.INTRODUCTION

At CERN,the Technical Control Room(TCR)monitors data coming from the electrical distribution,cooling water, air conditioning,vacuum,cryogenics,safety,and other systems.In this context,a Technical Data Server(TDS)has been defined and will provide data collected from the above equipment to high-level control software such as Human–Computer Interfaces(HCIs),the logging system and the alarm server.An expert system will be used to perform alarm filtering.

This project is being developed using the European Space Agency(ESA)PSS-05Software Engineering Standards [1].

The intention of this paper is to highlight the scope of the TDS project,the project environment and how we intend to achieve the project goals(methods,tools).There will also be a detailed description of the chosen middleware package, RTworks by Talarian.

II.MOTIV A TION FOR THE PROJECT

The project involves a redesign of the existing methods of acquiring and managing data used in the TCR.At present, data for the HCI and logging is polled from the equipment directly(top-down)and alarm data is handled by event-driven software(bottom-up).Data is acquired through a large distributed network that covers all accelerator sites:PS,SPS, LEP,Meyrin and Pr´e vessin.

The benefits of the TDS are numerous.It keeps a permanent image of all equipment attributes monitored by the TCR(100000points).It proposes a new,more reliable channel for alarm transmission to cope with alarm bursts and a centralized alarm reduction mechanism.The response time of the Uniform Man–Machine Interfaces(UMMIs: applications which display equipment states),is improved,to respond to data requests within one second.Equipment access is rationalized,as specific access routines are replaced by a generic addressing mechanism which allows both data retrieval and sending of commands.The use of an industrial middleware package decreases the maintenance effort for multiple client-server applications.The number of processes in each hardware element is decreased,due to the fact that multiple individual equipment access no longer takes place.Finally,the TDS offers a solution to the problem of supplying data to the increasing number of TCR applications users.The TDS provides high availability and reliability(24hours a day,365days a year)as required for the operation of CERN services.All data monitored by the system are defined in a unique reference database and identified by a unique tag[2].

III.THE ENVIRONMENT

The environment consists of a three-layer architecture[3]:the Control Room layer,the Front-End Computing layer, and the Equipment Control layer(Fig.1).The Control Room layer consists of HPUX servers(HCI,alarms,RDBMS)and X-Terminals.The HCIs are based on an XWindow–OSF/Motif user-interface management system and Dataviews[4]. The Front-End Computing layer consists of Front-End process computers(FEs),also called Process Control Assembly (PCA),based on PCs and VMEbus crates.They interface with variousfieldbuses and more particularly the MIL-1553fieldbus.