14 Nov. 2000EPICS Workshop - Oak Ridge1 DESY SCADA Experience Matthias Clausen DESY/ MKS-2

14 Nov. 2000EPICS Workshop - Oak Ridge2 Overview u What is SCADA (compared with DCS systems) u Where and Why are SCADA systems used u What do SCADA systems Provide? u Evolution u OPC for SCADA u Benefits u Experience from DESY u Outlook

14 Nov. 2000EPICS Workshop - Oak Ridge3 Data Server SCADA ? S upervisory C ontrol A nd D ata A cquisition Graphics and Batch processing Archiving, Logging, Access Control, Alarms Distributed database PLC’s Field Bus Data Server Control Programs ERP Systems Expert Systems

14 Nov. 2000EPICS Workshop - Oak Ridge4 What, Where and Why u What is “SCADA”and where is it used u Supervisory Controls And Data Acquisition u Application area : u Industrial processes: chemical, power generation and distribution, metallurgy, … u Nuclear processes: reactors, nuclear waste,... u Experimental physics: Tokamaks, HEP laboratories u Application size: u 20 K I/O to 450 K I/O, two examples of 1 M I/O under development u Why SCADA systems were evaluated for LHC SLC ? u Reduction of resources u CERN policy of “outsourcing”

14 Nov. 2000EPICS Workshop - Oak Ridge5 What do SCADA Provide? u Flexible and open architecture u Basic SCADA functionality u MMI u Alarm Handling and Trending u Access Control u Automation u Logging, Archiving, Report Generation u Interfaces to H/W and S/W u Interfaces to ERP- and Expert-Systems u Development Tools

14 Nov. 2000EPICS Workshop - Oak Ridge6 Generic Software Architecture Tren- ding Alarm Display Log Display Active X Controls Active X Container SCADA Client Recipe DB Recipe Managt Ref. DB AlarmLogArchive Report Gener. Log DBArchive DBSQLAlarm DB RT & Event Manager Data Proces SCADA Server RT DB ODBC DDE API/DLL Private Application EXCEL Driver PLC OPC Graphics Editor MMI Driver Toolkit Project Editor Export / Import Commercial DB Commercial Devel. tool ASCII Files ASCII File Editor SCADA Developt. Environt. Library Data R/W VME Client / Server - Publish / Subscribe - TCP/ IP

14 Nov. 2000EPICS Workshop - Oak Ridge7 SCADA functions u Logging, Archiving u Data stored in compressed and proprietary format u Logging / Archiving either for a set number of parameters or for a set period of time u Logging / Archiving can be frequency or event driven * u Logging of user actions together with a user ID u VCR facility for playback of stored data u Writing logs into RDB u Report Generation u Reports created using SQL type queries to the RTDB or logs u Automatic generation, printing and archiving of reports u Use of ‘components’ for report generation * ! DESY

14 Nov. 2000EPICS Workshop - Oak Ridge8 Interfaces to H/W and S/W u H/W u Multiple communication protocols supported in a single system (in particular CERN supported Field busses) u Support for major PLCs/DCSs but not VME u S/W u API u ODBC, DDE and OLE I/F to PC Products u OPC Client and OPC Server u ActiveX Containers u Web clients

14 Nov. 2000EPICS Workshop - Oak Ridge9 Development Tools u Project editor u Graphics editor u Configuration through parameter templates u Scripting language u Most processing tools based on IEC 1131 u Batch configuration according to S88.1 u Driver Development Tool Kit

14 Nov. 2000EPICS Workshop - Oak Ridge10 Benefits of SCADA u Standard frame for application u Rich functionality ( p-yrs investment) u Reliability and Robustness (very large installed base, mission critical processes) u Limited specific development u Technical support and maintenance u ….. Etc Enough arguments for the management to promote SCADA systems.

14 Nov. 2000EPICS Workshop - Oak Ridge11 u Namespace: flat vs. OO u System Load u Network u Processor u Project Management More Aspects to take into Account: u Configuration of SCADA Systems u Data Access Mechanism’s DESY Experience: Benefits? – not only

14 Nov. 2000EPICS Workshop - Oak Ridge12 Configuration of SCADA Systems Field Bus Data ServerPLC’sData Server Different Namespaces!!

14 Nov. 2000EPICS Workshop - Oak Ridge13 Configuration of SCADA Systems 2 nd PLC Programs Communication Processor Analog-Input Value-AI-0 Value-AI-1 Analog-Output Value-AO-0 Value-AO-1 Field Bus Analog-Input Vacuum_VALUE Pressure_VALUE Analog-Output Valve_1_OUT Heater_1_OUT Mapping SCADA

14 Nov. 2000EPICS Workshop - Oak Ridge14 Configuration of SCADA Systems 3 rd (Alarms) Analog-Input Vacuum_VALUE Pressure_VALUE Analog-Output Valve_1_OUT Heater_1_OUT SCADA Data Server (generic) Alarm scripts: IF (Pressure_VALUE > Pressure_HIHI_ALARMVAL) {Pressure_ALARM_HIHI=TRUE Pressure_ALARM_STATE=CRITICAL Pressure_ALARM_COLOR=RED } IF (Pressure_VALUE < Pressure_LOLO_ALARMVAL) {Pressure_ALARM_LOLO=TRUE Pressure_ALARM_STATE=ATTETION Pressure_ALARM_COLOR=BLUE } Alarm Generation

14 Nov. 2000EPICS Workshop - Oak Ridge15 The burden of flat namespaces:... A lot of individual tags! Vacuum_VALUE Pressure_VALUE Valve_1_OUT Heater_1_OUT Pressure_VALUE Pressure_HIHI_ALARMVAL Pressure_ALARM_HIHI Pressure_ALARM_STATE Pressure_ALARM_COLOR Pressure_VALUE Pressure_LOLO_ALARMVAL Pressure_ALARM_LOLO Pressure_ALARM_STATE Pressure_ALARM_COLOR 4 4 2

14 Nov. 2000EPICS Workshop - Oak Ridge16 Data Access Mechanism's u Alarm Server typically poll data from the data server ( -> impact on network bandwidth) More advanced techniques like publish / subscribe are available in some cases u Data from field buses are mainly polled Asynchronous protocols are difficult to handle Field Bus Data Server Alarm Server Polling

14 Nov. 2000EPICS Workshop - Oak Ridge17 DESY Experience 1 st u Namespace u Individual tags for each property blow up the namespace u Flat namespaces of thousands of tags can not be properly handled without adequate tools u Latest SCADA technology clearly shows the trend to support the definition of objects which cleans up the namespace u System Load u Additional –non standard- features like u calculating alarms for each channel u temperature conversions ( 6 th grade polynomial)... can cause a lot of overhead which needs to be taken into account for the calculation of the system load on process controllers ( here: in a SCADA-like DCS system)

14 Nov. 2000EPICS Workshop - Oak Ridge18 DESY Experience 2 nd u Project Management u Small systems can be easily handled with in-house personal u Big systems (several thousand of channels) should be coordinated by an engineering office because of: u The coordination of the Field Bus (PLC) databases and the SCADA databases u The knowledge of the various tools which come along with a SCADA system u One of the main arguments for SCADA systems is: outsourcing

14 Nov. 2000EPICS Workshop - Oak Ridge19 DESY Experience 3 rd u The SCADA project at DESY failed: u The project management of the company underestimated the necessary time to perform the engineering of the project. u The company underestimated the overhead for temperature conversions and the required calculations for alarm checking u As a result – the front end processors were not capable to handle the I/O and the calculations in the specified rate

14 Nov. 2000EPICS Workshop - Oak Ridge20 Preliminary conclusions u DCS system requirements are different from SCADA requirements u More frond end functionality u More record or device oriented configuration u System wide configuration tools are needed u Water tight specifications are necessary u DCS systems are more expensive than SCADA systems u A call for tender has to focus on either DCS or SCADA u SCADA systems are less expensive, but they offer different functionality u SCADA and DCS (mixed) can not selected by price

14 Nov. 2000EPICS Workshop - Oak Ridge21 DESY u Utility DESY use EPICS as a SCADA system u H1 is going to use PVSS for their slow controls u For TESLA a lot of components will be delivered by industry: u Various subsystems can be controlled by SCADA systems: u Utility Controls (water, energy, air, heating...) u Cryogenic Controls (cryogenic plants, cryogenic distribution) u Vacuum Systems (insulation vacuum, beam vacuum) u Problem: Integration of SCADA systems into accelerator controls

14 Nov. 2000EPICS Workshop - Oak Ridge22 That’s all Folks