A discrete event system: the CMS Tracker interlock Icaleps 2005 Icaleps 2005 Andromachi Tsirou, CERN The CMS Tracker interlock system The CMS Tracker and its environmentThe CMS Tracker and its environment The interlock system and its role in our work frameThe interlock system and its role in our work frame Input sensors and conditioning cardsInput sensors and conditioning cards Outputs, system modularity and hardware integrationOutputs, system modularity and hardware integration Information flow, communication and software integrationInformation flow, communication and software integration StatusStatus ConclusionsConclusions

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN The CMS Tracker

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN The CMS Tracker 3 sub detectors 6 partitions 10 7 readout channels 8,000 voltage channels >10 5 monitoring channels Power dissipation ~50 kW

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN The CMS Tracker

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN The Tracker’s environment The Tracker will have to be maintained at <-10 0 C, while its surrounding environment will be at ~18 0 C. The Tracker will be exposed to irradiation doses foreseen to be between 10 and 65 kGy and neutron and charged particle flows ranging from to particles/cm 2. The Tracker will share the CMS experimental cavern environment and resources. Power losses will be unavoidable as will be other harmful incidents (fire, flooding, etc).

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN The Tracker’s environment The Tracker has to be protected from temperature excesses;The Tracker has to be protected from temperature excesses; Temperature interlock The Tracker has to be protected from the presenceThe Tracker has to be protected from the presence of humidity. of humidity. Humidity monitoring The Tracker has to be protected from repeated powerThe Tracker has to be protected from repeated power on/offs; the power should be switched on and off in a predefined sequence. Power control The Tracker has to be protected from all cavernThe Tracker has to be protected from all cavern environmental hazards. DSS connection TheThe Tracker has only control over its own power.

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN The Interlock system must: Protect the Tracker by switching power off in theProtect the Tracker by switching power off in the “correct” method and in time; Evolve with the Tracker; accompany it during theEvolve with the Tracker; accompany it during the testing/integration period and during all its life at testing/integration period and during all its life at LHC. LHC. Have optimized sensor/interlock resolution.Have optimized sensor/interlock resolution. Be able to be integrated to the CMS experiment on time.Be able to be integrated to the CMS experiment on time.

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN The inputs conditioning only at ~100m conditioning only at ~100m The sensor requirements: radiation tolerant, tiny (mm) no magnetic field effects (4T) no magnetic field effects (4T) The temperature sensors : pt1000s,thermistors ( 3types ) The humidity sensors : radiation tolerant, able to sustain magnetic field. Digital inputs from “external” sensors

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN The inputs The sensor signals travel inside the Tracker on specially designed “control” cables ( ~1,600 ) for 100m in order to enter in the control system.The sensor signals travel inside the Tracker on specially designed “control” cables ( ~1,600 ) for 100m in order to enter in the control system. The thermistor and humidity sensor signals have to beThe thermistor and humidity sensor signals have to be conditioned before entering the readout of the control conditioned before entering the readout of the control system; the conditioning systems have to be under the system ; the conditioning systems have to be under the surveillance of the control system. surveillance of the control system.

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN The Outputs The output of the control system logic is distributed to the 200 power supply crates of the Tracker in the form of interlock signals;The output of the control system logic is distributed to the 200 power supply crates of the Tracker in the form of interlock signals; The power supplies provide bias both for the detectors and for the readout electronics chain.The power supplies provide bias both for the detectors and for the readout electronics chain. Each crate accepts up to four different interlock signals;Each crate accepts up to four different interlock signals; The granularity of action is that of a crate.The granularity of action is that of a crate. There is a hierarchical way of distributing the interlock.There is a hierarchical way of distributing the interlock.

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN The inputs : numbers Temperatures ~800 ~800 RH ~200 Other ~ 100 The control system (based on PLCs of the SIMATIC S7-300 family) S7-300 family) The Power Supply Read inputs Do logic Set outputs

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN System modularity-hardware integration TEC1 TEC2 TIB1 TIB2TOB2TOB1 Tracker Thermal screen

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN We try to treat the Tracker control system as a Discrete Event System. A Discrete Event System is a discrete-state, event-driven system, that is, its state evolution depends entirely on the occurrence of asynchronous events over time. We treat the Interlock system as such. EVENT: should be thought of as occurring instantaneously and causing transitions from one discrete state value to another. E.g.: a cable is disconnected; a cooling line gets clogged or a dry air pipe blows up. DES

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN GRAFSET

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN hardwired via DCU readout Information flow, communication and software integration cond. DB Measurements DCS layer (Diagnostic & Reconfiguration ) Drivers Hardware DCU Plotter (java) cond. DB DCU Filtre (XDAQ) DCU Filtre (XDAQ) DCU Filtre (XDAQ) i2o conf. DB DCU Thread FecSupervisor (XDAQ) DCU Thread FecSupervisor (XDAQ) DCU Thread FecSupervisor (XDAQ) PLC Plotter (java) PLC PLC Filtre (XDAQ) PLC T, H, other systems T, V, I Measurements

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN Status & Conclusions The Six large systems have to start being delivered in January Three shall remain for integration tests at CERN and three shall be shipped to laboratories outside CERN. They shall return “home” in order to form the control racks of the CMS Tracker.The Six large systems have to start being delivered in January Three shall remain for integration tests at CERN and three shall be shipped to laboratories outside CERN. They shall return “home” in order to form the control racks of the CMS Tracker. Six miniatures of the large systems are being deployed at CERN and in existing laboratories for more restricted roles but with exactly the same I/Os and functionalities.Six miniatures of the large systems are being deployed at CERN and in existing laboratories for more restricted roles but with exactly the same I/Os and functionalities. We are very tight on time schedule because we would like to have everything completely operational by spring 2006.We are very tight on time schedule because we would like to have everything completely operational by spring 2006.

A discrete event system: the CMS Tracker interlock Andromachi Tsirou, CERN Status & Conclusions The CMS Tracker infrastructure and environmental controls are fully based on standard industrial hardware. Although we needed to proceed to certain developments in order to integrate those standards to the general software and other requirements of a large HEP sub detector, the overall modularity, scalability and the up to now performance are satisfactoryThe CMS Tracker infrastructure and environmental controls are fully based on standard industrial hardware. Although we needed to proceed to certain developments in order to integrate those standards to the general software and other requirements of a large HEP sub detector, the overall modularity, scalability and the up to now performance are satisfactory.