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Introduction to Machine protection for CNGS (and TI2/8)

Introduction to Machine protection for CNGS (and TI2/8). J. Wenninger AB-OP. Introduction to the new Beam Interlock Systems CNGS extraction and protection requirements Interlocks : what, why, how? Operational aspects & issues. Introduction.

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Introduction to Machine protection for CNGS (and TI2/8)

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  1. Introduction to Machine protection for CNGS (and TI2/8) J. Wenninger AB-OP • Introduction to the new Beam Interlock Systems • CNGS extraction and protection requirements • Interlocks : what, why, how? • Operational aspects & issues CNGS Interlock System Training / J. Wenninger

  2. Introduction • The aim of this presentation is to give an overview over : • The new Beam Interlock Systems for SPS (and later LHC). In 2007 they will have replaced the present SPS Emergency System. • Details on the interlocking for the CNGS fast extraction. • Operational experience with the CNGS line and interlock system during the short CNGS run 18th -30th August 2006. • It is not possible to go into all details (time !). But the entire system is described in detail on the WEB page • https://cern.ch/sps-mp-operation/ CNGS Interlock System Training / J. Wenninger

  3. Beam Interlock Systems for SPS/LHC Requirements: • Generic solution for CERN • Reliable • Available • Fast CNGS Interlock System Training / J. Wenninger

  4. USER_PERMITS User System #1 User System #2 NOT MASKABLE Beam Interlock System BEAM_PERMIT Kicker System User System #n MASKABLE User System #m SAFE_BEAM_FLAG User Inputs SBF=distributed information to provide some flexibility while maintaining safety. • The user inputs are partitioned into NOT MASKABLE and MASKABLE inputs. • Note : MASKED signal = DISABLED signal. • NOT MASKABLE inputs are always active. • The MASKABLE inputs can be masked provided the SAFE BEAM FLAG is TRUE. • The SAFE BEAM FLAG is : • TRUE if BEAM_INTENSITY * BEAM_ENERGY is considered SAFE – i.e. no / little risk of damage. Needs input from BCT(s) and potentially (not at the SPS) main converter currents. • Presently distributed by the timing system (as a special telegram). CNGS Interlock System Training / J. Wenninger

  5. ■Standard interface for all interlock ‘clients’ at the SPS & LHC ■Allows direct connection with many different types of hardware platform (PLC, VME, etc…) ■Receives the USER_PERMIT signal (redundant) and transmits it to the nearest BIC ■On copper cable up to 1.2km Interlock Signal Connections User System Rack BIS Rack User System User Interface ‘A’ Permit ‘A’ Beam Interlock Controller ‘B’ Permit ‘B’ CNGS Interlock System Training / J. Wenninger

  6. BIS User Interface (CIBU) • Standard interface for the user signals. • Accepts various standards (VME/TTL/PLC) as input. • Installed in the ‘client’ rack. • Remote tests and diagnostics. • Redundant power supply. CNGS Interlock System Training / J. Wenninger

  7. BIS VME Crate • Cables are connected with a special patch panel at the back of the BIS VME rack. • NO cabling inside the rack: signal routing proceeds over printed circuit boards. • Fixed and well defined topology : cable  VME module One of the TT40 racks CNGS Interlock System Training / J. Wenninger

  8. of the BIS BIC Module • The Beam Interlock Controller or BIC is the VME module that collects the User-permit (interlock) signals. It is the heart of the interlock system! • Each BIC has 14+1 inputs : • 7 non-maskable HW inputs. Always active !! • 7 maskable HW inputs, that can be masked provided the ‘Safe Beam Flag is TRUE. At the SPS the ‘Safe Beam Flag’ is generated 1 second after the last injection from an intensity measurement of the hadron BCT in LSS3. It is distributed by the timing system to the BICs. Presently the limit is set to 1012. • 1 software input to be set through the standard controls network by SIS. • A standard BIC provides an output signal corresponding to the logical AND of all inputs. • IMPORTANT : unlike the SPS Emergency Dump System, the SPS BICs do not LATCH any signal ! • BIC modules can be connected to each other: • Interlock loop (fiber optic link), used for the rings. • BIC output  BIC User-permit input (‘daisy-chain’), used for transfer lines. • BIC internal history buffer: • All transitions are logged and time-stamped (to the ms). CNGS Interlock System Training / J. Wenninger

  9. Schematic BIS Hardware Layout Application Patch panel User Permits User Interface Control Network VME crate with LynxOS CPU + CTRP Modules User Interfaces Optical module 1 or 2 BIC modules to Kicker CNGS Interlock System Training / J. Wenninger

  10. User System User System User System User System User System User System User System User System SPS BEAM DUMP SYSTEM User System User System User System User System User System User System User System User System User System User System User System User System Future (2007) BIS Architecture SPS • One BIC / BA. • Connected by an interlock loop. • Connected to beam dump in BA1. • Details to be sorted out. BIC BPC BPC BPC BA6 BIC BIC BA1 BA5 2 2 Beam_Permit_Loops Clockwise & Anticlockwise • 2006 status : • 3 BICs for MKE & extraction BLMs in BA4 and BA6. • Used by new Software Interlock System (SIS). • Enters as ‘Summary BIS’ into SPS emergency dump system. BA2 BA4 User System BIC User System BIC User System User System BA3 BIC

  11. CIBC-TT40A CIBC-TT41A Temporary link/loop CIBC-TT41B CIBC-TT40B Extraction Interlocks for CNGS/TI8 Installed for 2007 Installed CIBC = BIC module CNGS target TT41 line Injection region & TI8 after TED TT40 line TI8 line Downstream part Upstream part CIBC-TI8up CIBC-TI8dw TED TED CIBC-EXT2 to MKE 4 CNGS Interlock System Training / J. Wenninger

  12. CNGS Interlocking Overview CNGS Interlock System Training / J. Wenninger

  13. East Extraction for CNGS Extract 2 x 10.5 ms long SPS batches, nominally 2.4e+13 protons per batch at 400 GeV EQUIPMENT: • 5 extraction kicker magnets (MKE4): • rise time: 1 ms, kick length: 11.3/12.1 ms, voltage: 50 kV • 6 septum magnets (MSE.418) CNGS • TPSG– protection element for MSE • 4 extraction bumper magnets: • 31.5 mm extraction bump • enlarged aperture quadrupole magnets • instrumentation CNGS Interlock System Training / J. Wenninger

  14. CNGS Extraction Timing • The CNGS cycle length is 6000 ms and the 400 GeV flat top is 90 ms long (from 4200 to 4290 ms). • The two extractions are programmed at 4220 and 4270 ms. • The RF extraction pre-pulse is programmed to arrive in the millisecond after (nominal) extraction time. • For the extraction kicker 2 timings/moments are crucial : •  13 ms before extraction trigger PFN charging (if EXTRACTION_PERMIT = TRUE) • arrival of extraction pre-pulse trigger magnets (if PFN charged and EXTRACTION_PERMIT = TRUE) The timing should be the same on ALL CNGS users ! Please do not change it - it has consequences on interlocks, logging… RF extr. pre-pulse (RF2) Legacy events New events

  15. CNGS Protection • Protection of the extraction channel and the transfer lines (TT40, TT41) – similar to the requirements for TI8 / LHC. • Protection of the T40 target (and what is behind) : • At high intensity it is important to hit the target within 0.5 mm of the axis (target rod  4 & 5 mm) to avoid damage to the rods. • A single (isolated) hit can (must !) be accepted, but we must avoid sending two consecutive extractions (50 ms) off-axis. T40 intercepts the fast extracted 400 GeV proton beam with two 10.5 µs long spills spaced by 50 ms. The nominal beam intensity is 4.8x1013 protons per cycle, the ultimate intensity 7x1013 protons. The nominal normalised emittance is ~ 12 mm mrad, the beam size @ T40 is ~ 0.5 mm. CNGS Interlock System Training / J. Wenninger

  16. CNGS BICs & User Signals in 2006 Red = un-maskable, Green = maskable,Magenta = Soft. Interlock In () : the interlock index that I will referred to later when I describe the inputs. The logical AND of all signals is sent as EXTRACTION_PERMIT to the extraction kicker MKE4 which fires only if the EXTRACTION_PERMIT is TRUE.

  17. Fast Extraction Interlock Types • For the CNGS/TIx fast extractions there are 3 types of interlocks based on : • Continuous surveillance of parameters. The associated permits change their state rather ‘rarely’ . • Vacuum, WIC, TEDs, target… • Pre-extraction surveillance where the user permits are evaluated a short time BEFORE extraction. The associated user permit is FALSE by default and switches to TRUE for a short time interval around extraction if all conditions are correct. • Surveillance of the beam position around extraction point and of the PC currents. • Post-extraction surveillance where the user permits are evaluated AFTER extraction. This type of surveillance concerns beam instrumentation. The associated user permit is switched to TRUE for a short time around extraction. The user permit is latched (FALSE) at the level of the client if a measured beam parameter is out of tolerance. • Beam losses and beam positions in the transfer lines. • Both Pre- and Post-extraction surveillance tasks are triggered by machine timing events coupled to the main extraction event. CNGS Interlock System Training / J. Wenninger

  18. Continuous Surveillance CNGS Interlock System Training / J. Wenninger

  19. Targets, Absorbers & Obstacles / 1 • Vacuum valves(1, 2) : • USER_PERMIT=TRUE only when all valves are OPEN. NOT MASKABLE ! • All valves are interlocked. • TBSE block(3) : • USER_PERMIT=TRUE ONLY when TBSE is OUT of beam. NOT MASKABLE ! • TT40 TED(4) : • USER_PERMIT=TRUEwhen theTED is IN beam or OUT of beam (both positions are SAFE). NOT MASKABLE ! • In 2007 are more subtle logic (with automatic masking/unmasking of downstream interlocks) will be implemented. • CNGS (decay tunnel) shutter(5): • USER_PERMIT=TRUE ONLY when the SHUTTER is OPEN (position ~ 0 mm). NOT MASKABLE ! • T40 Target(6,7): • 2 USER_INPUTs, one NOT MASKABLE, oneMASKABLE. • For normal operation USER_PERMIT=TRUE ONLY when the target barrel is positioned with a rod assembly in beam. • We (OP) have NO CONTROL over the target position ! CNGS Interlock System Training / J. Wenninger

  20. Targets, Absorbers & Obstacles / 2 • TL screens(8,9): • The TL screens have 4 positions: OUT, Carbon OTR, Titanium OTR and Alumina screen. • USER_PERMITs are MASKABLE. • USER_PERMIT = TRUE : OUT position + Carbon OTR • USER_PERMIT =FALSE: Al screen, Titanium OTR or device moving (should move during beam out). CNGS Interlock System Training / J. Wenninger

  21. Magnet Interlocks • A WIC (Warm MagnetInterlock Control) system surveys the magnet temperatures of TT40, TT41, TI8, TT60 and TI2 (10, 11): • USER_PERMIT=TRUE only when all temperatures are OK. NOT MASKABLE ! • When a sensor detects an over-temperature or a local IO module dies (partly installed in the tunnel), the system FIRST sets USER_PERMIT=FALSE, and 1 second later switches off the concerned PCs. • Provides 2 separate inputs for TT40 and TT41. • It is a PLC based system, at some time we should/will get the surveillance application. • MSE.418 magnet and girder state(12): • USER_PERMIT=TRUE ONLY when: • Girder is IN-BEAM and within tolerance (window of +- 2 mm, reference is HARDCODED). • Magnet temperatures & cooling are OK. • MSE PC is ON. • NOT MASKABLE ! • Whenever an interlock on the magnet is generated, the USER_PERMIT is switched to FALSE ~ 100 ms BEFORE the PC is switched off. CNGS Interlock System Training / J. Wenninger

  22. Miscellaneous Inputs • CCC button / OP inhibit(13) : • USER_PERMIT=FALSE if the button ‘LSS4 Inhibit’ is pressed (second button from the right). • NOT MASKABLE ! • Equivalent of the console switch for the fast extraction. • Horn & reflector status(14) : • USER_PERMIT=TRUE when both HORN and REFLECTOR are ON. MASKABLE ! • Hadron Stop Cooling(15) : • USER_PERMIT=TRUEwhen the cooling circuit of the CHGC hadron stop is running. MASKABLE ! • Fire Alarm(16): • USER_PERMIT=FALSE when a fire is detected in the CNGS target cavern. MASKABLE ! CNGS Interlock System Training / J. Wenninger

  23. Software Interlock System • The new SIS (Software Interlock System) that will replace SSIS (2007 ?!) provides two software interlock inputs. • It provides additional (and slower) cross-surveillance and diagnostics. Next year it will also directly cut the beam (based on destination) through the timing system. • TT41 software surveillance: • Summary of PC states (TT41), target position, BTV positions, TBSE position, Shutter, BLM gains (avoid saturation) and thresholds, etc is sent to BIC module CIBC.TT41A. • The status is refreshed for every CNGS user (CNGS1/2/3/4) – at the end of the cycle. • TT40 and LSS4 surveillance: • Summary of PC states (TT40 & LSS4), BTV positions etc is sent to BIC module CIBC.TT40B. • The status is refreshed for every CNGS or LHC user (CNGS1/2/3/4, LHC1/2, MD1/2/3/4) – at the end of the cycle. • CNGS Protection does not depend critically on SIS. In case of SW problems you can therefore mask channels that give problems. This year we had quite frequently problems with the PC surveillance, and frequently had to mask all PC interlock (will have to be fixed next year). CNGS Interlock System Training / J. Wenninger

  24. Pre-extraction Surveillance CNGS Interlock System Training / J. Wenninger

  25. Powering failures • Powering ‘failures’ are among the most likely and most critical failures : • Wrong converted setting  surveillance of the current VALUE. • Converter failure  FAST surveillance of the current CHANGE. Examples of simulated powering failures TT41 Main Bends Tol. Tolerance Tolerance CNGS Interlock System Training / J. Wenninger

  26. ROCS PC Current Surveillance • The ROCS system provides a pre-extraction surveillance, the so-called FEI (Fast Extraction Interlock). The current of selected converters has to match a reference within a pre-defined tolerance. The surveillance is performed at the last possible moment ~ 2 milliseconds before extraction. • This system provides in total 6 inputs to the BICs, all inputs are MASKABLE: • LSS4 bumper converters (H+V) (17) TT41 converters (20) • TT40 converters (18) MBI main bend converter (21) • MSE.418 converter (19) Interlock DCCTs for shared main converter (22) • Operational current tolerances : • MBHA, MBHC dipole strings 0.2% • Main dipole string 0.1% • Interlock DCCTs 1.0% • MBSG dipole string 0.1% • Septum 0.1% • Main quad strings (D/F) 0.2% • Matching quads 0.5% • Corrector magnets ~ 10 mrad • Bumpers ~ 1 mrad CNGS Interlock System Training / J. Wenninger

  27. ROCS Surveillance Timing • For each extraction, the ROCS system provides four 3 ms long pulses with PERMIT = TRUE (if all OK) which sets a strong constraint on the timing event sequence (minimizes possible errors). • The LEGACY events that trigger the ROCS are: • OEX.FINT1-CTM at -13 ms • OEX.FINT201-CTM at 0 ms (first extraction) • OEX.FINT202-CTM at 0 ms (second extraction) •  Extraction kicker triggers ~ Nominal Extraction Time + 800 ms (arrival time of pre-pulse) Do NOT change the delays !!!!!! PFN charge only starts if the PERMIT is TRUE ! CNGS Interlock System Training / J. Wenninger

  28. Shared Main Bend Converter Interlock DCCTs • The TT41 and TI8 main dipoles are powered by a single converter, with switches (presently mechanical, next year electronic) to send the current into the correct magnet string. • To ensure that the switch position is REALLY correct, we have 2 ‘dummy’ ROCS channels that have only an interlock DCCT but no converter. The names of the ROCS are DCCT_TI8 and DCCT_CNGS (also accessible from equipstate). • The 2 DCCTs are used to identify which branch is powered, and their current is surveyed like any other converter (22). MUGEF for ‘standard’ surveillance CNGS Interlock System Training / J. Wenninger

  29. FMCMs • The FMCM is a special high sensitivity device that monitors the current change of a circuit (through the voltage) and triggers an interlock when the current derivative is too large. • 3 FMCMs (Fast Magnet Current Change Monitors) are installed on the MSE.418(23), the MBSG.4000(24) and the MBG dipole string(25). The FMCM trigger thresholds have been determined by programming step functions into the converter reference (with and without beam). In all cases the position change @ target is maintained < 0.5 mm (as specified). • To avoid un-necessary triggering of the circuit during the converter ramps, the FMCMs are activated (input to TRUE) only at the end of the ramp when the currents stabilize. In addition a minimum current must be detected. The USER_PERMIT of the FMCMs is usually FALSE and switches to TRUE in a window of some hundred(s) milliseconds around the extraction. It switches to FALSE when the converter ramps down (looks like a failure…). CNGS Interlock System Training / J. Wenninger SC time (ms)

  30. Ring BPMs • A number of SPS ring BPMs in LSS4 are used to interlock the beam position at extraction as a pre-extraction surveillance (extraction bump amplitude) (26). • The interlock logic is implemented within the MOPOS system. • Unfortunately MOPOS remains fragile (~ one reboot required / day, gain changes) and this interlock is our ‘talon d’Achille’ ! Interlock timing for MOPOS CNGS Interlock System Training / J. Wenninger

  31. Ring BPM Settings • The nominal amplitude of the bump is 31 mm at BPCE.418 (corrected for BPCE non-linearity !) – this corresponds to ~ 29 mm on the normal display. The corrected value is available from the ‘Extraction Interlock’ menu in YASP (SPS ring, ‘Machine Specials’ • The tolerances on the positions are: • ± 1 mm  good protection • ± 2 mm ~ at the limit (fallback if problems) • A priori one could interlock any BPMs in sextant 4. But MOPOS cannot manage the data (too slow). • 8 positions (5 H and 3 V) are selected for the interlock around the extraction point (418). • The ‘minimum’ system corresponds to 2 H (416/418) and 2 V (417/419) monitors. CNGS Interlock System Training / J. Wenninger

  32. Ring BCT • For LHC / TI8 test an interlock on the beam intensity is provided by the ion BCT4 (27) . • The BCT can be configured to only provide USER_PERMIT=TRUE when the intensity is below a programmed threshold. The intensity measurement is performed 80 ms before extraction (warning event). • This signal is not used/activated for CNGS. The USER_PERMIT must always be TRUE during CNGS operation. CNGS Interlock System Training / J. Wenninger

  33. Post-extraction Surveillance CNGS Interlock System Training / J. Wenninger

  34. Transfer line BLMs • Since BLMs in TLs can only measure AFTER the ‘action’, they provide a Post-extraction surveillance.The USER_PERMIT is latched to prevent further extractions if an excessive loss is detected. • Two user permits are provided for TT40 (28)and TT41 (29). • The reset is done manually (for the moment via steering program). • The USER_PERMIT transition from FALSE to TRUE is triggered by the ‘-20 ms extraction pre-warning’ event. If there is no (abnormal) loss, the USER_PERMIT resets to FALSE a few milliseconds after the extraction. CNGS Interlock System Training / J. Wenninger

  35. Transfer line beam loss & thresholds • Beam losses in TT40 & TT41 normally are very low (< 0.3 mGray for 1013 protons). • When the C OTR screens are inserted losses increase to ~ 2 mGray in some locations. •  Thresholds to 5 mGray in TT41. • The gains must be ≤ 16 ! Saturation ! Surveyed by SIS ! • For the moment, the interfaces shown below are available from… the steering program !!! TT40 BLM losses & thresholds TT41 BLM losses & thresholds Ignore… BLM after TED : high threshold to avoid interlocks when beam is sent to the TED. CNGS Interlock System Training / J. Wenninger

  36. Transfer line BPMs • APost-extraction surveillance has also been implemented for the CNGS trajectory (30). • Each of the 23 H+V BPMs in TT40 (4 BPMs) and TT41 can be interlocked. They can be activated individually. Tolerances: • ±4 mm for 20 transfer line BPMs  TL aperture • ±0.5 mm for last 3 or 4 BPMs  target tolerance • The interlock is latched (reset through steering application). • A position is used for interlocking only if the BPM has seen beam (auto-triggered): to trigger the BPMs one needs one batch of ~ 2-3×1012 protons (or an equivalent DENSITY). • The interlock timing follows the same logic than for transfer line BLMs. CNGS Interlock System Training / J. Wenninger

  37. Transfer line BPMs /2 Example : reference trajectory for the CNGS pilot run Threshold ±4 mm Threshold ±0.5 mm Short-circuit on one electrode. De-activated for interlocking. Misalignment transfer line-target-horn CNGS Interlock System Training / J. Wenninger

  38. MKE • The MKE extraction kicker provides a slow control interlock to the interlock system (31) . • The MKE signal is only TRUE when the kicker is ON. NOT MASKABLE ! • Internally the MKE has an energy tracking system (from a mains DCCT in BA3). This internal ‘BETS’ (Beam Energy Tracking System) system enforces the following interlock logic: • Kicker voltage 50 kV (nominal) ± 2 kV. • Energy must be in a window of 400 ± 5 GeV. Timing of kicker, BIC permit and BETS: The BETS interlock is only visible in OASIS and on the scope display (example to the right) which is available under: http://kestek4/ When the BETS interlocks, the magenta curve is flat ! A symptom for a BETS interlock is that the MKE does not kick although the interlocks are OK! - PFN voltage - BIC permit - Beam - BETS window Extr. 1 Extr. 2

  39. Safe Beam Flag • Masking of any MASKABLE input to the CNGS BIC system is conditioned by the SPS safe beam flag (SBF). SBF = TRUE if the intensity is below a predefined threshold. • A MASKED INPUT is AUTOMATICALLY reactivated if SBF=FALSE. • SBF Generation: • The SPS high intensity BCT is used to measure the intensity 1 second after the start of the ramp (triggered by a timing event). • The intensity is sent to the SPS MTG and compared to the safe beam threshold to generated the SBF. • The SBF is distributed over the timing system to the BICs. • Presently the limit for a safe beam is set to 1012 protons. This is a rather conservative limit and it is difficult to obtain CNGS beams of such a low intensity. I have therefore suggestedto increase the limit to 3×1012 protons which should be sufficiently safe. CNGS Interlock System Training / J. Wenninger

  40. Extraction-Ring Interlock Systems Connection • Two systems that are part of the extraction interlock system are (also) connected to the ring BIC system: • The extraction kicker MKE dumps the beam: • When it is pulsing in local. • When the kick is enabled and the interlock system has not given green light for extraction. After three consecutive (same USER) cycles in such a condition the SPS Emergency System cuts all beam. • The BLMs in LSS4: • Typical loss on the first BLM ~ 10-20 mGray – threshold at 50 mGray. • The loss is due to beam in the gap. If losses become excessive, check the gap population with the fast BCT. Gap population depends on the PS CT, and our RF settings (injection phase, bfield, RF voltage on FB). • Do not increase the thresholds ! Radiation in ECA4 !! • ‘As usual’ : interlock is latched by SPS Emergency System after 3 consecutive interlocks (same USER !). • Fabio’s new application will be used from now on to read & control those BLMs. CNGS Interlock System Training / J. Wenninger

  41. Radiation in ECA4 Radiation in ECA4: H. Vincke CNGS Interlock System Training / J. Wenninger

  42. BIC Supervision CNGS Interlock System Training / J. Wenninger

  43. BIS Supervision Software • The supervision applications for the SPS BIC systems (ring and CNGS) are available from the SPS console manager under: • Start Tasks  SPS Control  SPS Beam Interlocks • Each ‘bubble’ on the top screens represents a BIC module, the color encodes the BIC output (RED=FALSE, GREEN=TRUE) and the state is sampled at ~ 1 Hz. Note that this is too slow to observe changes for the extraction where the signals are very short and fast. CNGS Interlock System Training / J. Wenninger

  44. BIC Supervision – Main Screen Safe Beam Flag status Software Interlock System Input • Clicking on a ‘bubble’ opens the main supervision screen for the corresponding BIC module. On the main screen : • Connected input list • Input status • Masks (status & actions) • Safe beam flag • Permit status • Refreshed at ~ 1 Hz. • From the main screen: • (Un-)masking of inputs. • History buffer view. • Expert screens view. • Bar graph view. Inputs 1 to 7 are always un-maskable Inputs 8 to 14 are always maskable Mask status CNGS Interlock System Training / J. Wenninger

  45. BIC Supervision – history buffer • The history buffer logs all transitions and signal changes (also masks and SBF) as well as the start of every cycle (as a marker). • Very powerful for debugging, but becomes complex when there are many signal transitions ! Time within SPS cycle in ms/ms State of BIC output Signal name / transition Timing marker : start of cycle Signal transition : (A) and (B) refer to the 2 redundant signals for each input !

  46. BIC Supervision – Bar Graph • The bar graph view shows the status of the inputs/output as a function of the CYCLE TIME: it is a graphical display of the history buffer. • Display signals for one SPS cycle, or a sub-range of a cycle (for example around extraction) • Refreshed every cycle (i.e. every 6-12 seconds) Depth in seconds wrt Time offset Time offset wrt start of cycle Check this box to hold selected time range values Check this box to freeze display Extraction permit switching to TRUE for extraction (3 ms wide)

  47. BIC supervision for CNGS operation Graphical display of all signals for a (successful) CNGS extraction… CNGS Interlock System Training / J. Wenninger

  48. Supervision Software – new ? • I have recently proposed to implement a new table display that would summarize the status at selected times (corresponding to the extraction): • If the output of the BIC is FALSE, the list of inputs that are false is listed. • This provides a simple snapshot of the system status at the time of extraction. • The depth of this table should be ~ 50 to 100 cycles… Same columns that are also found in the history buffer. List of inputs in state FALSE at the time of the snapshot, or indication for timing marker CNGS Interlock System Training / J. Wenninger

  49. Diagnostics software For continuous surveillance interlocks, the diagnostics is rather ‘easy’ since the errors are more or less static – one just has to find the appropriate application ! It is more tricky for highly dynamic interlocks …. CNGS Interlock System Training / J. Wenninger

  50. General Post-mortem • A post-mortem application to browse logged data has been written by Verena. It can be found in the console manager in the same place as other interlock stuff : • Start Tasks  SPS Control  SPS Beam Interlocks  Extraction post-mortem • This application is very powerful, but it can be tricky to start using it just when a problem appears ! • It is very useful to analyze trends, changes over a few hours… • Try it out when you have a quiet moment during a shift ! CNGS Interlock System Training / J. Wenninger

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