1. The Detector Control Power System of the Monitored Drift Tubes of the ATLAS Experiment Theodoros Alexopoulos NTU Athens TWEPP08 September 17, 2008 Naxos, Greece

2. Outline Introductory Remarks about DCS MDT in ATLAS Experiment Structure of DCS Power Systems for MDT Summary Detector Control System (DCS)

3. DCS - Introduction Detector Control Systems ◦ Systems to control (via computers) the operation of a HEP experiment ◦ Appeared in 1980’s ◦ Increasing Complexity of the Experiments ◦ Control of a large amount of parameters ◦ Check of the smooth operation of the experiment Characteristics ◦ Operators don’t need to be sub-detector experts ◦ Operation procedures become very easy ◦ Automatic Error Recovery procedures can be implemented

4. LAN-ETHERNET OPI Operator Interface OPI Operator Interface IOC Input/Output Cntrl IOC Input/Output Cntrl Standard DCS Model (Client-Server Model) OPI: Operator Interface, IOC: Input/Output Controller, IOS: Input/Output Servers IOS Input/Output Server IOS Input/Output Server Clients Servers Controllers

5. What does DCS involve? Control, Configuration, Readout, Monitoring of Hardware devices (but not readout of event data) Monitoring of external systems (LHC, Safety, Electrical, Gas, etc) Implementation of Finite State Machine behavior Communication with DAQ Logging of data, status, storage in database Partitioning

6. subDet 1subDet 2subDet 3 subSys 1subSys 2 Driver 1Driver 2 Device 1 central control Control Units Device Units DCS Architecture External systems

7. I/OControllers Analog/Digital channels, Fieldbuses fieldbuses SCADA OPI terminal Experiment Sub-Detectors & Experimental Equipment LHC Safety Server Beam Server Beam-line LHC data OPI WAN Remote Workstations Local Workstations I/O Servers distributed in Experimental area OPC Typical DCS Architecture (physical subsystem layout) Typical DCS Architecture (physical subsystem layout) bridge OPI terminal OPI terminal LAN-ETHERNET IOS DB server Oracle WAN laptop OPI Remote Users elmb caen-hv

8. Supervisory Control And Data Acquisition System: PVSS Commercial product PVSSII from ETM, Austria LHC wide decision Can be distributed over many stations Flexible and open architecture Basic functions for automatisation Standardized interface to the hardware Application programming interfaces

9. What is OPC? è OPC defines a standard to interface programs (SCADA, HMI) and hardware devices in a control system. è OPC provides a multi-vendor interoperability. No more specific drivers needed for each client è OPC (OLE for Process Control) is based on the MS object model COM/DCOM (Component Object Model). è OPC includes 3 interface specifications:  Data Access  Alarm and Event Handling  Historical Data Access Application XApplication Y Device ADevice B Application XApplication Y Device ADevice B OPC Interface OPC Server OPC

10. 10 LHC ExperimentsATLAS Diameter: 25 m Length: 44 m Weight: 7 kT ~100 M electronic chs 1150 MDT chambers 354 384 Tubes 214 Tonnes 725 m 3 Gas Volume 5520 m 2 Chamber Area A Toroidal LHC ApparatuS

11. ATLAS Inner DetectorCalorimeters Muons TRT SCT Pixel LArgTile TriggerPrecision TGCRPCMDTCSC 46m 25m TRT: Transition Radiation Detector SCT: Silicon Central Tracker TGC: Thin Gap Chamber RPC: Resistive Pad Chamber MDT: Monitored Drift Tubes CSC: Cathode Strip Chamber

12. Muon Spectrometer Two Basic parts Barrel και EndCap: ◦ Barrel: 3 cylinders (inner-middle-outer) ◦ EndCap: 3 disks Chambers: MDT, CSC, RPC, TGC 1150 MDT chambers 354 384 Tubes 214 Tones 725 m 3 Gas Volume 5520 m 3 Chamber Area

13. DCS Architecture in ATLAS DCS_IS Global Control Stations (GCS) CERN Magnet LHC DSS Operator Interface Data Viewer AlarmStatusWeb WAN Subdetector Control Stations (SCS) CICTile Pixel SCT TRT MDTTGCRPCCSCTDAQLAr Local Control Stations (LCS) High/Low Voltage GasAlignmentTempB-fieldJTAG Rod Power Front-End Systems

14. Finite States Machine (FSM) ATLAS MDT Barrel A EndCap A INNER MIDDLEOUTER ← GCS: Overall control of the detector ← SCS: Full local operation of sub-detector ← TTC Partitions → BMS1C14BML1C01 Barrel CEndCap C ← Layers ← Chambers State & Status Commands Structure of FSM: Definition: A finite state machine (FSM) or finite state automaton or simply a state machine is a model of behavior composed of a finite number of states, transitions between those states and actions.

15. PixelSCTTRTLArTileMDTTGCCSCRPCCIC ATLAS EMB-AEMB-BEMEC-AEMEC-CHECFCAL HVTHERMORODFECHV-PS Q2Q3Q4Q1 HV sector 1 HV sector 2 HV sector n Global Control Station Sub-detector Control Station DAQ Partition DAQ DDC Local Control Station Geographic partition Device Units Operator Interface Finite State Machine (FSM) Architecture The FSM (part of the JCOP Framework) is the main tool for the implementation of the full control hierarchy in ATLAS DCS It is envisaged that the shift operators will operate DCS ONLY through the Operator Interface (based on the FSM) and the PVSS alarm screen JCOP: Joint Controls Project

16. ATLAS DCS GCS SCS2SCS N TTC N.1 LCS N.1.1 Dev N-1 LCS N.1.2 Dev N... Shift Operator Detector Expert Another Detector Expert Operator Interface FSM (Partitioning)

17. Operator Interface FSM (STATE and STATUS) STATE READY NOT_READY ON STANDBY RAMP_UP ….to be defined by the user STATUSOK System works fine fine WARNING Low severity. System can go on working. ALARM High severity. Serious error to be fixed ASAP FATAL Very high severity. The severity. The system cannot system cannot work. work. Messages via a double Information Path – STATE & STATUS Messages via a double Information Path – STATE & STATUS STATE STATE defines the operational mode of the system (ON, OFF, etc) STATUS STATUS defines how well the system is working (OK, WARNING, ALARM, FATAL) Two parallel information paths. E.g. HV system is in RAMPING_UP state (which takes several minutes) and an error triggers. The error is propagated through the STATUS while keeping the same STATE

18. ATLAS DCS at First Beam Events

19. CAEN Power Supplies modules Crates Boards LV: A3025 & A3016 HV: A3540P Mainframe CAEN SY1527 Branch Controllers A1676 19

20. Structure of MDT PS Eltx Room SY1527 System mainframe Branch Controller Experiment Area Easy Module Control Logic Control Bus 48V Power Source Power Fail Use Interrupt 48V Power Source Power Line P. Service Line 48V Backup Battery 64 Crates

21. PS OPC server EM SY1527 OPC server OPC Client OPC Client PS1 PS2PS3CSC Run a single OPC server on PS1 pc (scattered system) PS2 Barrel System PS3 EndCap System EM OPC Client

22. PVSS datapoints Datapoints that correspond to hardware modules (channels, boards, crates, branch controllers, mainframe) Datapoints that correspond to the chambers Internal datapoints for the FSM for the OPC Server (communication with hardware) for the RDB manager (archiving of datapoint elements) Alarms are activated for the datapoints and their elements

23. FSM trees One FSM tree is implemented for each partition Hierarchy is set for the parts of the system (nodes and their children) Commands and states propagate correctly

24. FSM panels

25. FSM panels- EndCaps

26. Present status of PS system

27. Barrel All chambers are incorporated in the system having LV modules HV modules for all chambers in all sectors

28. Endcaps Both Big Wheels and Small Wheels (one for each side) are incorporated to the system having both LV and HV modules

29. Summary ATLAS PS MDT DCS is a Robust System Is being used… Delivered & Tested on Time Members of ATLAS NTU-Athens DCS group: Ex-members T.Alexopoulos, T. Argyropoulos, E. Gazis, M. Bachtis, A. Iliopoulos E. Mountricha, C. Tsarouchas, G. Tsipolitis