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Workshop on the Use of Ethernet as a Fieldbus CERN, 28 September 2001 Ethernet in the MO/AA control systems F.Havart ST/MO History of use in both groups 1996 SPS SPS UNSMOKE system 1999 CDIN and CGAZ safety systems 1999-2000 EREM project 2000-2005 CSAM project Ethernet Token Ring PLC PCA MIL1553 ECA ECA CDIB PROFIBUS WAGO DP Operator Console Contacts I/O SERIAL RS LINK Middleware TCP/IP Integration of PLCs and SCADA I/O - PLC - Fieldbus Contacts I/O SERIAL RS LINK Why Ethernet? Completely distributed control environment Wide areas to cover Large number of data to process No real need for determinism characteristics Available everywhere at CERN Well adapted for event driven processes Why Ethernet? Complex architecture but easier to stick to state of the art safety and risk analysis methodology High reliability and/or availability Industrial equipment use possible Modularity Return of experience Reference: 48 PLC working 24h/day 356days/year for 4 years, 15000 data points Conclusion so far: Hardware is extremely reliable (both front end and network equipment) Remote maintenance/upgrade/diagnostic facility Very efficient coding/cabling for dry contact/analog data points Ethernet is a valid medium as fieldbus as long determinism is not needed BUT ... Return of experience Development cost sometimes high therefore not recommended for short life cycle projects PLC manufacturers are not open minded Not very well suited for ASCII protocol translation Industrial philosophy for SCAM doesn’t fit the standard computing one Future? Future MO architecture for control system will use PVSS SCADA and Ethernet LHCX PVSS PVSS UI Configuration database LHC PVSS ST/AA PVSS TCR PVSS Databus driver GIF PVSS Direct equipment data acquisition Future? Industrial equipment is already available (including embedded web server) for 5 years Industry seems to favour Ethernet and the trend is to use it at the lowest level of the acquisition layer Direct connection serial/Ethernet medium will solve problem of proprietary system and protocols