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					       SNS Machine Protection System
            Final Design Review

                           Introduction

                                Dave Gurd

                        Tuesday, September 11, 2001




SNS Integrated Control System
     Review Committee Members



        Kelly Mahoney          (Jefferson Lab)   Chair
        Mike Thuot             (LANL)
        Ken Reece              (SNS/ORNL)
        George Dodson (SNS/ORNL)




SNS Integrated Control System
     Presenters



        Coles Sibley           Cognizant Engineer
        Saeed Assadi
        Ron Battle




SNS Integrated Control System
          Scope (2) – Personnel Safety Systems
              are not under Review Today

             Target Protection System

             Personnel Protection System

             “High QA” System

             Machine Protection – Latched

             Machine Protection – Auto reset

             Run Permit (Software Layer)




SNS Integrated Control System
     Scope

         This is the Final Design Review for the SNS Machine
          Protection System Hardware.

         The Software System that uses this hardware will be
          reviewed separately, and at a later time.




         The “High QA System” discussion is a Preliminary
          Design Review” only, preparatory to a planned
          Project Change Request.



SNS Integrated Control System
                 System under review is in WBS 1.9.2
                                                  (Global Systems)


                                                                                                                             ICWG



     1.3                1.4              1.4 Cryo              1.5               1.6                 1.7           1.8          1.9
  Front End            Linac          (JLAB, ORNL)            Ring              Target          Instruments     Facilities    Controls
   (LBNL)             (LANL)                                 (BNL)             (ORNL)          (ORNL, ANL)    (ORNL, CM)




    1.9.3              1.9.4               1.9.10            1.9.5               1.9.6                           1.9.8             1.9.9
  Front End            Linac               Cryo              Ring               Target                         Facilities        Personnel
   Controls           Controls            Controls          Controls           Controls                        Controls           Safety



  1.9.2 “Global” Controls: (Network, Timing, Protection, Control Room, Labs, Applications, System Software)




                                      1.9.1 Integration & Management




SNS Integrated Control System
                     Charge to the Committee
      Is the Scope well defined and understood?
      Are all the Requirements understood and well-defined? Is the
       hardware proposed flexible enough to do what is required?
      Are all of the Interfaces – internal and with other systems –
       appropriate and well-defined?
      Does the Design presented meet the requirements?
        » Issues? Anything missing? Anything dumb?
      Are there any Safety or QA issues requiring attention?
      Is the Cost and Schedule credible with respect to the design and
       to the project schedule?
      Are there any major Unresolved Issues?
      Bottom Line: Can we proceed with Procurement and Fabrication?


SNS Integrated Control System
                                     Schedule

        10:00 – 10:15 Intro                    Dave Gurd
        10:15 – 12:00 MPS                      C. Sibley
          » 10:15 – 10:35      MPS Overview (Latched and Auto Reset)
          » 10:45 – 11:45      MPS Software, MPS Hardware, Altera Code
          » 11:45 – 12:00      Cost, Schedule
        12:00 – 1:00 Lunch
        1:00 – 1:15   Target Protection        Ron Battle
        1:15 – 1:30   Diagnostics              Saeed Assadi
        1:30 – 2:00   HQA System               C. Sibley
        2:00 – 2:15   Cost Schedule            C. Sibley




SNS Integrated Control System
                  Machine Protection System

                       Final Design Review

                          September 11, 2001


                                Coles Sibley



                                               2000-0xxxx/vlb



SNS Integrated Control System
     Related Documents

        High QA MPS Description (Sibley)
        Interface Requirements Document for MPS and Front End
         Equipment (Sibley)
        SNS MPS VME/PMC Module Design (Sibley)
        MPS System Requirements Document (Sibley)
        MPS Interface Requirements Document (Sibley)
        SNS Beam Loss Policy (Dodson)
        ASD Control of Beam Power (K. Reece)
        Preliminary Safety Assessment Document (PSAD)
        Copper damage from fast Beam Loss (Shafer)
        Front End Cutoff Devices (Staples)




SNS Integrated Control System
     Questions for Committee

        Mode Masking is critical. Are Hardware / Software protections
         presented adequate?
        Are we Interlocking ourselves to TOTAL SAFETY- NO BEAM?
          » Availability verses reliability?
          » Flexibility vs. reliability? (Commissioning)
        Should corrector power supply ON status be an MPS Input?
          » Presently NO. Will keep real estate available for the future.
        Are Redundant PLC’s and Current sensors required?
          » Is FPS-Latched OK for redundancy?
          » Is Voltage and current read back OK verses 2 Zero Flux?
        Layout of inputs indicates a better arrangement is 16/0, or 0/16
         instead of 8/8. Very minimal coding change.


SNS Integrated Control System
     Machine Protection System (10:00 – 12:00)

         Machine Protection System Overview
          » Mode and timing info throughout MPS Talks
         MPS Software Overview
         MPS Hardware, Firmware
         Cost
         Schedule


      Acronyms
          »   FPS     Fast Protect System
          »   FPL     Fast Protect Latched
          »   FPAR    Fast Protect Auto Reset
          »   BLM     Beam Loss Monitor


SNS Integrated Control System
       Machine Protection is a Global Subsystem

                                                                                                               ICWG
                                                                                                             include JLAB



     1.3        1.4           1.5               1.6                   1.7           1.8          1.4 Cryo          1.9
  Front End    Linac         Ring              Target            Instruments     Facilities   (JLAB, ORNL)       Controls
   (LBNL)     (LANL)        (BNL)             (ORNL)            (ORNL, ANL)    (ORNL, CM)




    1.9.3      1.9.4        1.9.5               1.9.6               1.9.7         1.9.8           1.9.10               1.9.9
  Front End    Linac        Ring               Target            Instrument     Facilities        Cryo               Personnel
   Controls   Controls     Controls           Controls            Controls      Controls         Controls             Safety



                             1.9.2 “Global” Controls
                                 - 1.9.2.3 Machine Protection



                         1.9.1 Integration & Management




SNS Integrated Control System
     MPS Design Assumptions

        Four layers of protection!
          » High QA (Hardware)         PLC
          » Hardware / Software        (Fast Protect System)
          » Software                   (Run Permit System)
        Machine Protection System is not a “Safety Class” or “Safety
         Significant” System.
        SNS will be built and commissioned in Phases, MPS must
         accommodate this schedule, (Flexible and Reliable).
        Reliability – The Machine Protection System must inhibit the
         beam when required. It must fail in a SAFE state.
        Availability – The machine availability should be as high as
         possible. The MPS must be easy to configure and have a
         “friendly” operator interface. False trips must be minimized.



SNS Integrated Control System
     MPS - Layered Protection
                         Protection            System                                      Shutdown
                                                                  System Inputs
                          System              Description                                  mechanism




                                                                                                                   Safety
                                                                   Mercury Sensors




                                                                                                                   Class
                        Target Protection
                                                 Hard Wired         Temperature              AC Breakers
                            System
                                                                      Flow, etc




                                                                                                                   Significant
                                                                                        AC Breakers in front end




                                                                                                                     Safety
                            Personel         Hard Wired and PLC       Chipmunks,
                                                                                             electronics &
                        Protection System        application          Doors, etc.
                                                                                            power supplies

                                                                    Magnet Shunts
                                                    PLC
                              MPS                                     PPS Inputs            65 kV Supply
                                                 Control net
                              HQA                                  Beam Diagnostics       RFQ Power Supply
        Increasing QA




                                                  FLEX IO
                                                                  Dump, TGT Controls




                                                                                                                   Non Safety Class Systems
                                                                   Valve Status
                                            3 MHz carrier link    Power Supply
                        Fast Protect                                                     65 KV switch
                                             KEY Bypassing            Status
                          Latched                                                      RFQ Power Supply
                                             PLC Bypassing        Machine Mode
                                                                      Inputs
                                            8 MHz carrier link    Loss Monitors
                        Fast Protect
                                            Software bypass         RF Status                RFQ Drive
                        Auto Reset
                                             Software Trips       Machine Mode
                                                                                       Fast Protect System
                                                 EPICS            EPICS Channel
                        Run Permit                                                        Beam Permit
                                               Application        Access Inputs
                                                                                             System



SNS Integrated Control System
         SNS Accelerator Timing Sequence

    Informational Events, non critical timing                             Time Critical Events, (Hardware is counting)


  Real-Time                      RTDL parameter
  Data Link                       transmission
   (RTDL)
                             snapshot,                                                                                linac beam
                RTDL         1Hz, 10Hz,                              System xxx                      MPS Inhibit                    extract
                                                                                                                          end
              transmit         etc...             cycle start          Trigger

                    mode                                                           MPS Fault       Inject                             Save
                                    RTDL valid
                                                                                                                                      Data

 event link
                                                                                           Rf, High voltage                       beam
                                                                                                Gates                          accumulation
                                                                                                                   Anytime
 machine                                                 Anytime            Anytime

 Master Trigger Generator

      -3 ms              -2 ms        -1 ms          0             1 ms         2 ms        3 ms            4 ms        5 ms          6 ms


                         MPS Inputs
                         Event Link
                         RTDL Data



SNS Integrated Control System
     Mode Definitions


        Machine Modes             Beam Modes
         »   PPS /Beam Permit       »   Off
         »   Ion Source             »   Standby (RFQ RF gate)
         »   D-Plate                »   Diagnostics (10 usec)
         »   Linac Dump             »   Diagnostics (50 usec)
         »   Injection Dump         »   Diagnostics (100 usec)
         »   Ring                   »   Full Pulse Width (1 msec)
         »   Extraction Dump        »   Low Power (7.5 kW)
         »   Target                 »   Medium Power (200 kW)
                                    »   Full Power (2 MW)




SNS Integrated Control System
     Background - SNS Events (Prioritized)

        5 thru 36 - Operating Mode (same        as RTDL frame data)
          »   Hardware / Software from PLC through EPICS
               – Beam dump, power limit, Pulse length limit
               – Injection rates limited by dump power and pulse width
               – DTL for commissioning only

                         Off           10 usec      50 usec    100 usec 1 msec
              SRC                  5            6            7         8        9
              DTL                  5           10           11        12       13
                      10 usec 50 usec 100 usec 7.5 kW    200 kW 2 MW
          LDMP               14      15      16       17
          IDMP               18      19      20       21       22
          Ring               23      24      25       26
          EDMP               27      28      29       30
          TGT                31      32      33       34       35    36




SNS Integrated Control System
     MPS Fast Protect System

        Fast Protect Auto Reset (20 microseconds)
          » Inhibits beam for duration of macro pulse by disabling
            FPS_PERMIT_LINK_B carrier to the front end. Restores Fast
            Protect link for next pulse if fault restored to normal.
        Fast Protect Latched System (20 microseconds)
          » Latches fault conditions until fault clears and Operator resets
            condition. FPS_PERMIT_LINK_A carrier interrupted and
            inhibits beam through front end devices.
        Run Permit System (1 second)
          »   Coordinates machine mode changes.
          »   Scans IOC configurations for Software Configuration errors.
          »   EPS interface for masking equipment inputs.
        High QA MPS (2 Pulses)
          »   Latched in Hardware
          »   Redundancy through FPLS inputs



SNS Integrated Control System
     Copper Damage from Fast Beam Loss (R. Shafer)

            Energy      dE/dx     time Bragg ratio    time ----------Range----------
            (MeV) MeV-cm2/gm (dE/dx) us          (Bragg) us gm/cm2              cm
               2.5       69.6         6          3        2       0.023    0.0026
                 5      44.18        10        3.8        3       0.069    0.0077
                10      27.09        16          4        4     0.2172     0.0243
                15       20.1        22        4.2        5     0.4323     0.0485
                20       16.2        27        4.7        6       0.709    0.0795
                50       8.09        54        5.3       10       3.502    0.3926
              86.8       5.37        81        6.3       13       9.197    1.0311

     Time to reach thermal stress at front surface – column 3
     Estimated time to reach the thermal stress limit at the Bragg peak - column 5

     Conclusion
     Based on these estimates, it is apparent that significant damage can occur in
     the DTL unless the MPS Fast Protect can shut down the beam in less than
     about 5 microseconds for beam losses at E<= 7.5 MeV. For the CCL (E>87
     MeV), 20 microseconds is adequate. There is no risk of damaging the RF
     structures during commissioning with single 52-mA, 600-ns long minipulses.

SNS Integrated Control System
     MPS Response Time (Estimate)
       Comm Room                                      Total Beam Total Beam
       (End of)    Min MPS Max MPS Beam flight after fault after fault
       (IOC's)     Total       Total       Time       Min         Max
       MEBT (2)        6.4E-07     8.4E-07    1.4E-07     7.8E-07     9.8E-07
       DTL (4)         1.3E-06     2.2E-06    1.4E-07     1.5E-06     2.4E-06
       CCL (5)         2.0E-06     3.3E-06    1.1E-06     3.1E-06     4.4E-06
       Mbeta (4)       2.6E-06     4.1E-06    1.5E-06     4.0E-06     5.6E-06
       HB5 (4)         2.9E-06     4.1E-06    1.7E-06     4.6E-06     5.7E-06
       HB11 (4)        3.3E-06     4.5E-06    1.9E-06     5.2E-06     6.3E-06
       End SRF (4)     4.0E-06     5.2E-06    2.1E-06     6.1E-06     7.3E-06
       Ldmp (4)        4.2E-06     4.8E-06    2.3E-06     6.6E-06     7.2E-06

   Fiber speed = 0.65C
   Copper speed = 0.65C
   MPS Board delay = 75 nsec




SNS Integrated Control System
     MPS Fast Protect System Layout
                                                                                                Front
                                                                                                                    LINAC          RING               RTBT       Target
                                                                                                 End


                                                                 27.3 us




                                                                                                Protect




                                                                                                                     Protect




                                                                                                                                                      Protect




                                                                                                                                                                 Protect
                                                                                                                                   Protect
                                                                                                Inputs




                                                                                                                     Inputs




                                                                                                                                                      Inputs




                                                                                                                                                                 Inputs
                                                                                                                                   Inputs
                                                                                                 Fast




                                                                                                                      Fast




                                                                                                                                                       Fast




                                                                                                                                                                  Fast
                                                                                                                                    Fast
                                                                           Fault
                                                                                                Fa
                                                                                                   ult            LEBT                                                       ct
                                                                                                                 Chopper                                                   te
                                                                                                                                                                      Pro    r
                                                                                            RFQ                                                                     st rrie
                                                                                                                                                                  Fa Ca
                                                                                            Drive



                                                                                                    Front
                                                                              Event                                       LINAC      RING               RTBT       Target
                                                                                                     End
                                                                             System




                                                                                                    Permit




                                                                                                                          Permit




                                                                                                                                                        Permit




                                                                                                                                                                   Permit
                                                                                                    Inputs




                                                                                                                          Inputs




                                                                                                                                                        Inputs




                                                                                                                                                                   Inputs
                                                                                                                                     Permit
                                                                            "ABORT"




                                                                                                                                     Inputs
                                                                                                    Beam




                                                                                                                          Beam




                                                                                                                                                        Beam




                                                                                                                                                                   Beam
                                                                                                                                     Beam
      MEBT       Ldump




                                                                               Fa
                                                                                  ult
                                                                                                         Faul
                                                                                                             t        Ion Source                                                it




                                                                                        Fault
                                                                                                                       65 Kv PS                                             rm
                                                                                                                                         Extraction                       Pe r
                                                                                                                  Faul                    Kickers                       am rrie
                                                                                                                      t                                               Be Ca



    MPS Inputs   MPS Inputs
                                                                                                        RFQ
                                                                                                     Power Supply




                                                         Xdump
                                                    MPS Inputs
        RFQ          SRF        Idump
    MPS Inputs   MPS Inputs   MPS Inputs

                                                          RTBT
                                                    MPS Inputs
      LEBT           CCL        RING                                                        Target
    MPS Inputs   MPS Inputs   MPS Inputs                                   MPS Inputs



         Src         DTL        HEBT            RING                                            RTBT
    MPS Inputs   MPS Inputs   MPS Inputs     MPS Inputs                    MPS Inputs

      0.8 us       5.6 us        5.8 us        8.2 us                                           8.2 us




                     65 kV        MPS            RFQ
                      RFQ        Master          Drive
                     HVPPS         Machine
                                    mode
SNS Integrated Control System
     MPS Master
                                  MPS Master, 12 IN links, 2 Out links

              FPL, FPAR                                                                      7 MPS carrier
        Status (Interlock inputs)                                                         links, 1 per dump
                                                                                                 From Target
                                                     Standard MPS
                                                      PMC Module                             From E_Dmp
          PLC contacts for
                                                                                                 From Ring
          software bypass                             Tgt
                                                       E_Dmp                                     From I_Dmp

    HQA PLC Input                                           Ring                             From L_Dmp

                          FPL, FPAR Inputs                      I_Dmp
                                                                                                 From D_Plt
                                                                   L_Dmp
                                                                                                  FPL Carrier
                                                                        D_plate                  FPAR Carrier
                                                 FPL Carrier
                                                                        Ion_Source
                                                 FPAR Carrier



                                                                               8 MPS Systems
                                                                               2 PPC MV2100
                                                                            2 PMC_Span modules
                    Front End Shut off devices



SNS Integrated Control System
     Front End Shut Off Devices

        MPS HQA - PPS                                                  Only if MPS detects fault
        HQA- 65 kV power supply                                        OK
        HQA - RFQ Power supply (Interlock)                             OK, but 5 min. recovery
        FPL - 65 kV fast switch                                        OK, 100 msec’s
        FPL - RFQ Power supply                                         OK, but 5 min. recovery
        FPAR - RFQ RF drive                                            OK, Off, move gate, ON
        FPAR - LEBT Chopper                                            Fails unsafe* – BUT Fast
          »    MEBT Chopper                                             Could damage chopper
          »    RF Reference line                                        Long recovery
          »    LEBT Valve                                               Power limit, Not a beam stop
          »    Beam Stop                                                none
          »    +/- 40 kV lens supplies                                  Not 100 %
          »    RF Plasma Source PS                                      Thermal instabilities
          »    RF plasma source gate                                    OK for short time
        * PAC 2001 paper, SNS Beam Chopping and its Implications for Machine Protection, L. Doolittle, C. Sibley




SNS Integrated Control System
     Fast Protect – Auto Reset

        ALARA – Pulse Width Modulation
        Tuning Aid, ALARA
        Concentrates Permit Inputs
        Inputs Bypassed by Mode
        Inhibits carrier link to disable Beam
        Inputs:
          » Loss Monitors
              – Software trip points, bypass
          » RF Low level Controls (Maybe latched)
        Software maskable
        Auto mask sets (Wire Scanner)



SNS Integrated Control System
     Beam Loss Monitors (Saeed’s Talk)

        Integration Time – Set in Hardware
        Trip point limits – Software adjustable - EPICS
        Dose Rate Calibration
        Masking Capabilities – Software Masks
        Wire Scanner Masks – Auto mask sets for each W.S.
        Placement – Near Quadrupoles, Redundant coverage
        HV Supply – 1 HV supply takes down every other BLM
        Configuration Control
          » Commissioning vs. Run Periods




SNS Integrated Control System
     EDM EPICS Loss Monitor display




SNS Integrated Control System
     Auto Reset Inputs

                       Fast Protect, Auto Reset
                     Loss         LLRF          Total


          LEBT                                            0
          MEBT                                            0
          RFQ                                1            1
          DTL                    12          6           18
          CCL                    24          4           28
          SRF                    64         92          156
          HEBT                   55          2           57
          RING                   87          4           91
          RTBT                   43                      43
          Total                 285        109          394


SNS Integrated Control System
     Fast Protect - Latched System


        Concentrates Permit Inputs
        Inhibits carrier link to disable beam
        Devices bypassed by Jumper or PLC and Software
          » Configuration determined on a case by case basis
        Inputs Bypassed by machine mode (event link)
        System Configuration Control
          » Equipment maintained in locked racks
          » Documentation control of changes
          » System verification after changes




SNS Integrated Control System
     Fast Protect - Latched Inputs

        Power supply status
         » NO-Fault signal removed when interlock chain dropped or
           power supply receives OFF command
        Valve Status
         » No Fault signal when valve is open and NOT closed
         » (intermediate states are faults)
        Linac RF Status
         » RF Enabled Signal. Could be auto reset input
        Target Status
         » Input comes from the target control system.
         » Response should be faster than target shutdown signal.
         » Time Stamp verifies MPS ACTED FIRST




SNS Integrated Control System
     Fast Protect – Latched Inputs

        Dump Status
         » Passive Dump Status from PLC
        Vacuum Status
         » Poor integrated vacuum levels
        Timing System Status
         » Ring RF required for IDMP, RING, EDPM, and target modes
         » Local Oscillator allowed for LDMP, Dplate, and Ion Source modes
        PPS Input
         » PPS search status will latch off beam
        Beam Collimator’s
         » Water cooling
        LEBT Chopper
         » Required for Ring Operation



SNS Integrated Control System
     Fast Protect - Latched Inputs


          Loss monitors (Near BCM’s, HIGH QA)
          Current monitors
            » Integrated current monitors
            » Pulse Width violations
            » Idmp over current monitor
          HARP
            » Beam current intensity
          SEM
            » With each HARP
          Beam Position Monitors
            » Beam off target/dump violation
          Wire scanners, Faraday cups
            » “Home” Limit switches




SNS Integrated Control System
     Fast Protect - Latched Inputs

          Beam Loss Accounting system
            » Software integrated loss
          EPICS Alarm Inputs
            » EPICS Alarms for any PV can trigger latched input on a board
              level or input signal level.
          Injection Kickers
            » Power supply status
            » Waveform errors
            » Kicker pair matching
          Extraction Kickers
            » PS Status
            » Kickers Charged
          Ring RF



SNS Integrated Control System
     Latched Inputs

                         Fast Protect Latched Inputs
                RFHV PS I    Wire Harp Loss Kick Dmp/Tgt Vac Total
                        Mon.Scan.                  Coll. Other Inputs

        LEBT              5                                   1     6
        MEBT        1    17                                   1    19
        RFQ         1     1    1     1    1                   1     6
        DTL         3     0    1     6    2              8   18    38
        CCL         4    73          8                       20   105
        SRF        15    58    1    29                   1    1   105
        HEBT        1    54    1    14    2   2          2    2    78
        RING        2   195               2   2    8     4    2   215
        RTBT             91    2     4    4   4   14     2    2   123
        Total      27   494    6    62   11   8   22    17   48   695
     Includes Corrector Power Supplies


SNS Integrated Control System
     Number of MPS Systems


                          IOCS                 Total Latched   A-Reset
                hprf vac H2O ps       cryo BLMIOC's MPS        MPS

        LEBT                      1               1        1          0
        MEBT                                      0        3          1
        RFQ       1   1   1       1               4        1          1
        DTL           1                      1    2        4          3
        CCL       2   1   1    1             1    6       14          4
        SRF       7   1   4    1        4    2   19       14         20
        HEBT      1   1        2             2    6       10          8
        RING      1   2        5             3   11       27         12
        RTBT          1        1             2    4       16          7
        Total    12   8   6   12        4   11   53       90         56




SNS Integrated Control System
     MPS Input Bypass Mechanisms

        Mode Mask
          » Global database contains operating mode dependant devices.
            Devices not required for present mode are masked through
            hardware. Masks changed with database reconfiguration and IOC
            reboot.
        Jumper / Key / PLC Bypass
          » Software bypass requires set of closed contacts from a jumper,
            key, or PLC contacts.
        Software Bypass
          » If hardware configuration allows, input bypassed through software
            with appropriate EPICS Access Security permissions.
        The installation of bypass jumpers will be determined on a case
         by case basis by committee. Configuration control is monitored
         by RPS through EPICS.


SNS Integrated Control System
     Wire Scanner (Layered) Protection

     1.   Application Requests W.S. Mode, receives “SW KEY”
          » Run permit won’t allow long pulse until APP releases key
          » Program crashes, etc. require manual intervention, verification
          » MODE changed to 10, 50, or 100 usec as appropriate

     2.   IOC Receives Request for scan
          » Motor Record is locked by mode (Allowed by low PW MODE)
          » MODE == SHORT_PULSE, scan starts

     3.   MPS Hardware input masked by MODE (Not software)
          » Limit switch will cut off beam if not masked by MODE MASK
          » MODE changes while wire off stops -> Beam cut off
          » Motor breaks -> Manual intervention required to get wire out of
            beam



SNS Integrated Control System
     MPS Conclusion

        Several layers of protection, Defense in Depth
        System is flexible, easy to add / delete sensors as required
        Ability to mask through software will increase availability
        Easy to run during phased installation.
        Hardware enabling SW masks allows configuration control
         where required, flexibility to mask at will, with same hardware.




SNS Integrated Control System

				
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