1. The Architecture, Design and Realisation of the LHC Beam Interlock System Machine Protection Review – 12 th April 2005

2. benjamin.todd@cern.ch LHC Beam Interlock System 2 of 49 The LHC Beam Interlock System 1. Overview and Architecture -History -Specification -BIS Design -Communication strategies -EMC -Testing, Installation, Commissioning and Starting LHC 2. Dependability Analysis -Reliability, Safety and Maintainability -Typical Figures 3. Summing Up -Typical Response -Next goals

3. benjamin.todd@cern.ch LHC Beam Interlock System 3 of 49 The LHC Beam Interlock System 1. Overview and Architecture -History -Specification -BIS Design -Communication strategies -EMC -Testing, Installation, Commissioning and Starting LHC 2. Dependability Analysis -Reliability, Safety and Maintainability -Typical Figures 3. Summing Up -Typical Response -Next goals

4. benjamin.todd@cern.ch LHC Beam Interlock System 4 of 49 A bit of history System architecture Basic development Current Loops Fibre Optic ‘Permit Loops’ Masking Dependability & EMC Programmable Logic Tested in TI8 AUTUMN 2003 Tested in TI8 AUTUMN 2004 Testing in SPS AUTUMN 2005 2002-2003 2004 2005 2006 SPS, CNGS, Sector 7-8 Installation & Commissioning 2007 Remaining LHC Installation & Commissioning BIS 2005 Beam Interlock System Proposed BNL / DESY systems used as a basis 2001

5. benjamin.todd@cern.ch LHC Beam Interlock System 5 of 49 Design Specification This presentation considers only the LHC BIS! 1. A CERN-wide generic Beam Interlock System 2. Fast 3. Safe 4. High Test Coverage 5. Maintainable 6. Monitorable 7. Cost Effective 8. Deterministic LHC, SPS, CNGS etc. ~70μs over 28km Requesting Beam Dump = SIL 3 Low repair time Self-Diagnosing Provides first Post Mortem info On startup – ‘As Good As New’ Protects $$$ but need not be $$$ Know what it’s going to do & when

6. benjamin.todd@cern.ch LHC Beam Interlock System 6 of 49 Function BIS Both-Beam Beam-1 Beam-2 153 User Systems distributed over 28kms LHC has 2 Beams Some User Systems give simultaneous permit Others give independent permit

7. benjamin.todd@cern.ch LHC Beam Interlock System 7 of 49 Types of User In LHC, BIS forms a transparent layer from User System to Beam Dump

8. benjamin.todd@cern.ch LHC Beam Interlock System 8 of 49 Types of User In LHC, BIS forms a transparent layer from User System to Beam Dump

9. benjamin.todd@cern.ch LHC Beam Interlock System 9 of 49 Types of User In LHC, BIS forms a transparent layer from User System to Beam Dump

10. benjamin.todd@cern.ch LHC Beam Interlock System 10 of 49 Beam Permit Loops & BICs 10MHz Square wave generated at IP6 -Signal can be cut by any Controller -Signal can be monitored by any Controller When any of the four 10MHz signals are absent at IP6, BEAM DUMP! 4 fibre-optic channels from Point 6 1 clockwise & 1 anticlockwise for each Beam Beam Dump Beam-1 and Beam-2 Beam Interlock Controllers (BIC) 16 BICs - Two at each Insertion Point Up to 20 User Systems per BIC 6 x Beam-1 8 x Both-Beam 6 x Beam-2 Beam-1 / Beam-2 are Independent!

11. benjamin.todd@cern.ch LHC Beam Interlock System 11 of 49 Controller Block Diagram

12. benjamin.todd@cern.ch LHC Beam Interlock System 12 of 49 Controller Block Diagram

13. benjamin.todd@cern.ch LHC Beam Interlock System 13 of 49 Controller Block Diagram

14. benjamin.todd@cern.ch LHC Beam Interlock System 14 of 49 Mission Critical Information Flow Full Redundancy… 2 User Permits PER BEAM - Treated Identically, in SEPARATE HARDWARE Safe Beam Flag Redundant – if in doubt NOT SAFE User Interface Beam-1 BIC

15. benjamin.todd@cern.ch LHC Beam Interlock System 15 of 49 Mission Critical Information Flow User Interface Beam-1 BIC User Interface has Unique ID Number Different connector genders & sizes are used for safety

16. benjamin.todd@cern.ch LHC Beam Interlock System 16 of 49 RS422 communication to User Beam-1 User Interface Beam Interlock Controller USER_PERMIT.A USER_PERMIT.B BEAM_PERMIT _STATUS BEAM_PERMIT _STATUS MONITORING CHANNEL MONITORING CHANNEL TESTING CHANNEL TESTING CHANNEL

17. benjamin.todd@cern.ch LHC Beam Interlock System 17 of 49 RS422 communication to User Beam-1 User Interface Beam Interlock Controller USER_PERMIT.A USER_PERMIT.B BEAM_PERMIT _STATUS BEAM_PERMIT _STATUS MONITORING CHANNEL MONITORING CHANNEL TESTING CHANNEL TESTING CHANNEL

18. benjamin.todd@cern.ch LHC Beam Interlock System 18 of 49 RS422 communication to User Beam-1 User Interface Beam Interlock Controller USER_PERMIT.A USER_PERMIT.B BEAM_PERMIT _STATUS BEAM_PERMIT _STATUS MONITORING CHANNEL MONITORING CHANNEL TESTING CHANNEL TESTING CHANNEL

19. benjamin.todd@cern.ch LHC Beam Interlock System 19 of 49 EMC Combat…

20. benjamin.todd@cern.ch LHC Beam Interlock System 20 of 49 Sub-System Block Diagram Beam Interlock Controller Maximum ~1200m Typically ~3500m Beam-1 Clockwise Anti-Clockwise Beam-2 Clockwise Anti-Clockwise Safe Beam Flags Beam-2 Safe Beam Flags Beam-1 Typically ~300m

21. benjamin.todd@cern.ch LHC Beam Interlock System 21 of 49 HW Test, Install & Commission Installation & Commissioning of LHC BIS 1.Power-Soak (Run-In/Burn-In) 2.Installation in Machine 3.Users can switch USER_PERMIT = FALSE on request 4.Locally verified 5.Once Point complete, information stored in a Data-Base for on-line testing

22. benjamin.todd@cern.ch LHC Beam Interlock System 22 of 49 Online Test Critical Testing Verify Permit Loop Function and Timing

23. benjamin.todd@cern.ch LHC Beam Interlock System 23 of 49 Online Test Critical Testing Verify Permit Loop Function and Timing Permit ‘A’ Monitor LBDS (IP6)

24. benjamin.todd@cern.ch LHC Beam Interlock System 24 of 49 Online Test Critical Testing Verify Permit Loop Function and Timing Permit ‘B’ Monitor LBDS (IP6)

25. benjamin.todd@cern.ch LHC Beam Interlock System 25 of 49 Online Test Critical Testing Verify Permit Loop Function and Timing User #100 Permit ‘B’ Monitor LBDS (IP6)

26. benjamin.todd@cern.ch LHC Beam Interlock System 26 of 49 Online Test ? ? ? Non-critical Testing 1.Re-built and verify Database – Cabling 2.Verify secondary circuits, power supplies etc. All part of ensuring system is ‘As Good As New’ on startup.

27. benjamin.todd@cern.ch LHC Beam Interlock System 27 of 49 Startup BIC 4 BIC 8 BIC 2 BIC 6L LBDS BIC 6R Generator PERMIT ‘A’ LBDS_USER_PERMIT INITIALISE_LOOP LOOP_INIT = FALSE USER_PERMIT = FALSE LBDS_USER_PERMIT = FALSE

28. benjamin.todd@cern.ch LHC Beam Interlock System 28 of 49 Startup BIC 4 BIC 8 BIC 2 BIC 6L LOOP_INIT = FALSE USER_PERMIT = TRUE LBDS_USER_PERMIT = FALSE LBDS PERMIT ‘A’ LBDS_USER_PERMIT INITIALISE_LOOP Generator BIC 6R

29. benjamin.todd@cern.ch LHC Beam Interlock System 29 of 49 Startup BIC 4 BIC 8 BIC 2 BIC 6L LOOP_INIT = TRUE USER_PERMIT = TRUE LBDS_USER_PERMIT = FALSE LBDS PERMIT ‘A’ LBDS_USER_PERMIT INITIALISE_LOOP Generator BIC 6R Generator needs 10MHz INPUT to Latch-On ONLY set for ~250us HARDWARE INTERNAL RESET

30. benjamin.todd@cern.ch LHC Beam Interlock System 30 of 49 Successful Startup BIC 4 BIC 8 BIC 2 BIC 6L LOOP_INIT = TRUE USER_PERMIT = TRUE LBDS_USER_PERMIT = FALSE LBDS PERMIT ‘A’ LBDS_USER_PERMIT INITIALISE_LOOP BIC 6R Generator needs 10MHz INPUT to Latch-On ONLY set for ~250us HARDWARE INTERNAL RESET Generator

31. benjamin.todd@cern.ch LHC Beam Interlock System 31 of 49 The LHC Beam Interlock System 1. Overview and Architecture -History -Specification -BIS Design -Communication strategies -EMC -Testing, Installation, Commissioning and Starting LHC 2. Dependability Analysis -Reliability, Safety and Maintainability -Typical Figures 3. Summing Up -Typical Response -Next goals

32. benjamin.todd@cern.ch LHC Beam Interlock System 32 of 49 FMECA Failure Modes, Effects and Criticality Analysis In what way can something go wrong?… …when it does go wrong, what happens to the system?… …and just how much of a problem does this cause? FMECA starts at the Component Level of a system MIL-STD-1629FMD-97MIL-HDBK-338MIL-HDBK-217

33. benjamin.todd@cern.ch LHC Beam Interlock System 33 of 49 FMECA Conclusions User Interface During one year it’s probable that for all User Interfaces 0-1 will fail during a mission causing a Beam Dump 1.47E-08 is Probability of a both channels failing blind in the same User Interface SIL 3 75 Simultaneous Beam Dump User Interfaces 39 Independent Beam Dump User Interfaces 10 Hour LHC mission 400 Missions per year

34. benjamin.todd@cern.ch LHC Beam Interlock System 34 of 49 FMECA Conclusions 75 % Analysed System

35. benjamin.todd@cern.ch LHC Beam Interlock System 35 of 49 Redundancy Remove All Redundancy… Remove User Input Redundancy… All User Interface Power Supplies are REDUNDANT REDUNDANT VME Power Supplies are anticipated… 1 False Beam Dump p.a. less

36. benjamin.todd@cern.ch LHC Beam Interlock System 36 of 49 The LHC Beam Interlock System 1. Overview and Architecture -History -Specification -BIS Design -Communication strategies -EMC -Testing, Installation, Commissioning and Starting LHC 2. Dependability Analysis -Reliability, Safety and Maintainability -Typical Figures 3. Summing Up -Typical Response -Next goals

37. benjamin.todd@cern.ch LHC Beam Interlock System 37 of 49 Delta-t for a Point 2 Beam Loss 6.0μs 4.1μs 57.6μs0.5μs0.1μs2.1μs ~70μs MAXIMUM Problem Detected Beam Dump Waiting for abort Typically 1.5 μs Worst Case Delay

38. benjamin.todd@cern.ch LHC Beam Interlock System 38 of 49 A bit of history System architecture Basic development Current Loops Fibre Optic ‘Permit Loops’ Masking Dependability & EMC Programmable Logic Tested in TI8 AUTUMN 2003 Tested in TI8 AUTUMN 2004 Testing in SPS AUTUMN 2005 2002-2003 2004 2005 2006 SPS, CNGS, Sector 7-8 Installation & Commissioning 2007 Remaining LHC Installation & Commissioning Beam Interlock System Proposed BNL / DESY systems used as a basis 2001 Long Term testing Further Analysis of Dependability Mass Produce Commission Install 2007 – LHC BIS installed, commissioned, ready. 3 SPS BICs by November

39. benjamin.todd@cern.ch LHC Beam Interlock System 39 of 49 FIN

40. benjamin.todd@cern.ch LHC Beam Interlock System 40 of 49 BIC Patch Panel Cabling Burndy 12 Female Burndy 19 Female Burndy 12 Male Connected DIRECTLY to the rear of the P2 VME connector (extender) Securely fastened in place, vibration of fans no problem DEPENDABLE, one of the best architectures for reliable design PCBs not wires - No risk of cross connection / bad cables Genders Rear View Of VME Chassis

41. benjamin.todd@cern.ch LHC Beam Interlock System 41 of 49 User Interface & Cabling CIBU Details A single User Interface exists for simultaneous and independent operation – saves space – more reliable DUAL power supplies, redundant, monitorable INPUT Configuration A user gives 2 signals for each beam – small current loops Accommodates all the different user hardware 5V 12V 24V etc etc

42. benjamin.todd@cern.ch LHC Beam Interlock System 42 of 49 Diagnosis & Standard Functions Direct data from CIBU by Monitoring Test Mode Status (1 bit) Test Channel Status (1 bit) Test Logic Status (1 bit) Unique CIBU ID (10 bits) Number of Reception Errors (8 bits) Permit A State (1 bit) Permit B State (1 bit) Beam Permit Status State (1 bit) Permit A RS422 Fault (1 bit) Permit B RS422 Fault (1 bit) Beam Status RS422 Fault (1 bit) CIBUT (Tester) Attached (1 bit) PSU 1 Status (1 bit) PSU 2 Status (1 bit) Commands to CIBU by Testing Test Mode (1 bit) Test Channel (1 bit) Test Logic (1 bit) Soft Reset (1 bit) Direct data from CIBT CIBT Alive (1 bit) Boxes Alive (14 bits) Cumulative BER per CIBU (14 x 16 bit) Cable Delay (Calc.) per CIBU (14 x 16 bit) Direct data from CIBC Current State Permit As (14 bits) Current State Permit Bs (14 bits) Beam Permit Loop States (4 x 3 bit) RS 422 faults (60+ bits) Core Beam Number (2 bits) History Buffer (??) All data is moved to the Controller Core and can be read out by VME access Software has to reassemble the information correctly Provides initial Post Mortem Diagnosis

43. benjamin.todd@cern.ch LHC Beam Interlock System 43 of 49 PSU Redundancy = AVAILABLE Add Redundant VME PSU… PSU 3U About 1 less False Dump p.a.

44. benjamin.todd@cern.ch LHC Beam Interlock System 44 of 49 RS422 communication to User USER_PERMIT.A USER_PERMIT.B BEAM_PERMIT_STATUS CIBU_MONITORING CIBU_TEST MAX3440E EMC Excellent Slew Rate Limited Fail Safe Short Circuit Proof Fault Pins DC Mode - Simplex MAX489E Full Duplex Comms ~60-80kbps Manchester Encoded DC Balanced Monitoring Channel Testing Channel

45. benjamin.todd@cern.ch LHC Beam Interlock System 45 of 49 INIT BIC 4 BIC 8 BIC 2 BIC 6L LOOP_INIT = TRUE USER_PERMIT = TRUE LBDS_USER_PERMIT = FALSE LBDS PERMIT ‘A’ LBDS_USER_PERMIT INITIALISE_LOOP BIC 6R Generator needs 10MHz INPUT to Latch-On ONLY set for ~250us HARDWARE INTERNAL RESET Generator