MPS - Commissioning Plans

1. MPS - Commissioning Plans • Quick MPS System Overview • Run Permit System • Fast Protect Auto Reset • Fast Protect Latched • High QA (Hard Wired) MPS System

2. 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.

3. MPS - Layered Protection

4. MPS Commissioning (Verification, systems checked previously without beam, Commissioning and testing) • Run Permit System (1 second) • Verifies IOC configuration and beam line equipment status. • MPS masking, Beam Power limit verification • Fast Protect Auto Reset (20 microseconds) • Beam Loss Monitors • Beam Current Monitors • Fast Protect Latched System (20 microseconds) • Power Supply status, RF, Kicker status • System cooling status (Collimators, dumps, etc) • Etc. • High QA MPS (~ 33 msec) • Magnetic Field limit(s) verification • Beam Diagnostics verification, calibration, testing

5. MPS Fast Protect System Layout

6. MPS Shutoff Equipment • Hard Wire Protect • RF drive to RFQ Power Supply interlocks • 65 KV Power Supply Interlocks • Fast Protect – Auto Reset • RF drive to RFQ • LEBT Chopper • Fast Protect - Latched • 65 KV Power supply • RFQ Power Supply • Run Permit • Fast Protect - Latched • Fast Protect - Auto Reset • ( Time Line Decoder (un-schedule all beam) )

7. MPS - Fast Protect Inputs • LLRF Inputs could be auto reset (FPAR) • ~50% of corrector supplies will not initially be MPS inputs • HEBT 12/18, RING 12/126, RTBT 12/19 • BLM’s could be Latched, as determined during commissioning

8. Bypassing MPS Inputs • Allow easy bypass (Software Masking) • Different rules for commissioning and operations • Commissioning, FPAR devices can be masked • Commissioning, FPL – subset of Quads and correctors can be masked, all dipoles and rest of quads need ASD Radiation safety approval. • Commissioning team – ASD-RS should agree on list before commissioning. • Easy OPI for verifying, changing software MASK. • MODE masks are defined by ASD-RS, not easily changed.

10. Run Permit System – Tasks • Machine Mode Setup • Machine Mode (Dump) and Beam Mode (Power, Width restrictions) Selection (From High QA System) • Longitudinal pulse profile verification and selection • Verifies machine setup before changing mode • Schedules Machine Sequence • Keeps Beam, RF, Modulator gates in sync • Schedules Pulse Profiles at requested rate • Calculates / verifies table checksums (pulse to pulse) • Operator Interface to MPS • Control and Status Displays • Software Masking of inputs / Trip limit Controls • Hardware configuration verification • SNL task scans IOC hardware configuration for verification

11. Machine Modes Ion Source D-Plate Linac Dump Injection Dump Ring Extraction Dump Target Beam Modes Beam Off Diagnostics (10 usec) Diagnostics (50 usec) Diagnostics (100 usec) Full Pulse Width (1 msec) Low Power (7.5 kW) Medium Power (200 kW) Full Power (2 MW) Run Permit System – Mode Definitions • Machine mode selected by Key switch in control room, Beam Mode selected by Key or software. Switches read by High QA MPS system.

12. RPS – Operating Envelope Calculations

13. User Beam Profile Request

14. MPS Top Level Screen

15. Run Permit System – Operator Interface

16. Typical Top Level Screens • Global Software Mask Status Display • BLM Trip Point Display • Time / Fault display line • Post Mortem playback, Loss verses RF, etc • Time Line Recorder • Timing system faults, missing events, extra events, etc • PPS Status, Beam line readiness, etc • Fault by system, Fault by area • Beam Profile scheduling, Rate requests, etc. • Requests for specific displays seen elsewhere appreciated, a quick hand sketch is useful.

18. Fast Protect – Auto Reset • ALARA – Pulse Width Modulation, Tuning Aid • Concentrates Permit Inputs • Beamline Inputs Bypassed by Mode • Inhibits carrier link to disable Beam • Typical Inputs: • Loss Monitors • Time Line Recorder (Noise detected on Event Link) • Differential current monitors • Auto resets for next beam pulse, Latches to FAULT state after N trips in M pulses • Auto mask sets(MODE MASK) (Wire Scanners) • Mode allows WS to be bypassed, SW Mask bypasses WS input

19. SNS BLM SYSTEM DESIGN CRITERIA • Upper end signal: (Fast Protect Auto Reset) • Maximum beam loss of 1 % at a single location • 35-50 kHz signal BW • Beam interrupt via MPS based on integrated loss during pulse ( 10 μsec response) • Lower end signal: (Beam Loss Accounting System) • Set by 1 W/m requirement for maintenance • Must resolve 1% of 1 W/m but at BW of < 1 Hz • Warning only after extended period of loss (1 minute) • (Saeed Assadi, MPS FDR slides)

20. BLM-- Specification: Fast Loss:(Determine thresholds during commissioning) 1)10 µsec Detect-to-Beam Inhibit time.2) Programmable threshold, each detector, level changes/macro-pulse3) Each detector maskable (eliminate bad channels, permit studies resulting in higher than normal losses) Single output line/analog crate Long-term: (Calibration Studies) 1) Low level loss: "Soft" alarm through network or2) Programmable threshold, each detector,3) Each detector maskable (eliminate bad channels, permit studies resulting in higher than normal losses) Single output line/analog crate Local Data Storage: "Flight-Recorder Mode, 60 (1-second) records of "Detailed Losses" for each detector. Available for read-back on beam abort. In-Situ System check: On-line check of all detectors, connections and electronics by cycling HV Off/On.

21. BLM AFE Configuration

22. Beam and Loss Display (Simulated data II)

23. LINAC Dose Rate: ** Data is provided by Franz X Gallmeier.

24. LINAC Dose Rate (Simulated data) Distance along LINAC  Time 

25. Beam Loss Monitors (Commissioning) • Verify BLM Operation (Part of BLM / Diagnostics commissioning plans) • MPS • Measure (Verify) Integration Times (1 % Loss) • Determine Trip Point Limits for each BLM • Determine Radiation Dose Calibration • Calibrate losses in units of W/m • Verify Masking Capabilities (Software masks) • Verify Wire Scanner Masks (BLM Mode masks) • BLM Accounting • Calibrate low loss measurements • Change vacuum by order(s) of magnitude? • See Saeed’s slides from Ring commissioning meeting in Dec and slides from MPS FDR: • http://www.sns.gov/projectinfo/ics/192/1923/1923.html

26. Commissioning activities • Select device and mask (or desensitize) adjacent devices • Loose beam, verify time response • Log MPS input fault time • Log Front end shutdown time • Verify response time with diagnostics: • Current monitors, analog signal, scope mode • Fast Loss Monitor(s) • BPM Power (Amplitude) • Verify Loss mechanism (Change vacuum, monitor response) • Determine appropriate trip levels for commissioning, operations • Poor vacuum conditions, Energy changes, Tune changes (Instabilities) • Calibrate differential current monitors vs. Beam loss monitors • Identify, Eliminate(minimize) sources of false trips • Beam noise (50 amps @ 1MHz), Kicker noise, etc.

27. Conclusions: • SNS expects to maintain losses below 1Watt/meter over most of the Accelerator in order to allow hands-on maintenance. As such the BLM system will play a major roll in commissioning. • Important loss mechanisms include gas stripping, magnetic stripping and Halo generation from “mismatches”. We hope to use the BLM system to confirm the models and set the limits for the BLM-to-MPS trip levels. • Loss Monitor system will provide signals to the MSP system which are not modifiable by software (a layer of protection). • HARPS and specialized edge loss detection diagnostics are under studies but not included in the base-line systems yet.

29. Fast Protect - Latched System • Concentrates Permit Inputs • Latches carrier link in FAULT state to disable beam • Input bypassing allowed with Jumper, Key or PLC • Beam line inputs bypassed by machine mode (event link) • Equipment maintained in locked racks • Documentation control of changes • System verification after changes • When MPS inputs need bypassing for beam studies, Software masking will be available as required. (Masking some devices will need the approval from Radiation safety committee)

30. Power supply status (Fault when PS is not ON) Valve Status (Fault when valve is not OPEN) LLRF RF Status (Fault when PS is not Enabled) Target Status Response should be faster than target shutdown signal. Time Stamp verifies MPS ACTED FIRST Dump Status (Fault when all dump sensor not OK) Loss monitors (High QA chipmunks) Timing System Status Ring RF required for IDMP, RING, EDPM, and target modes Local Oscillator allowed for LDMP, D-plate, and Ion Source modes PPS Input PPS search status will latch off beam Fast Protect - Latched Inputs

31. Vacuum Status – Valve closures operate trip defined below. Integrated vacuum levels produce EPICS Alarms, which could shut off the beam (MPS). MPS trips on VALVE Closure. Vacuum Level – MPS trip levels Vacuum Level Requirements SystemDesign Conditioning Operational(1) Document TripTrip FE 5x10-7 1x10-6 5x10-6 Front End Systems SRD DTL 1x10-7 1x10-6 1x10-6 Linac Systems SRD CCL 5x10-8 1x10-6 5x10-7 Linac Systems SRD SCL 1x10-9 1x10-6 1x10-8 Vacuum System Interrupts (2) Coupler 1x10-8 1x10-6 1x10-7 Vacuum System Interrupts (3) HEBT 5x10-8 1x10-6 5x10-7 Ring and Transfer lines (4) Ring 1x10-9 1x10-6 1x10-8 Ring and Transfer lines RTBT 1x10-8 1x10-6 1x10-7 Ring and Transfer lines (1)   Actual trip points can vary and will be set during commissioning. (2)   Gate valves close if vacuum > 1x10-9 longer than 3600 seconds or > 10-6 ASAP. (3)   Inhibit RF and Beam if pressure >10-8 for 10 seconds, 10-7 for 1 second, or 10-6 ASAP. (4)   Estimated losses due to H- stripping (50% H ~10-19 cm2/atom, 50% Oxygen, Nitrogen ~10-18 cm2/atom) is 0.3 nA/m at 5x10-8 Torr.

32. Injection Kickers Extraction Kickers Ring RF Current monitors HARP – Backup to HQA-MPS SEM Possible backup to HARP Beam Position Monitors Beam off target/dump violation Fast Protect - Latched Inputs

33. EPICS Alarm Inputs EPICS Alarms for any PV can trigger latched input on a board level or input signal level. MPS Verification Software SNL program verifies jumper settings, Latches beam off in case of discrepancy. Beam Loss Accounting Integrated loss sets Alarm, could trip beam Beam Current Accounting Fast Protect - Latched Inputs

35. Injection Kicker • 2 Horizontal, 2 Vertical pairs, 8 power supplies • Power supply status inputs to MPS-FPL • Each kicker in a pair should be matched • Fault on unmatched waveforms ? • Run Loss studies on unmatched waveforms. • Sensitivity studies on painting schemes • 2 kHz comparators for Reference and Shunt

36. Injection Foil • Foil Failure • Beam Loss Monitors • HARPS • Integrating Current Monitor • Peak Current Monitor • Foil Video monitor • Foil Motion • Low power mode required? (LANSCE allows) • LVDT – Motion range available • Limit Switches • Foil Position • Use Mode Mask to allow beam for BLANK foil position or Phosphorous screen in place

37. Ring RF MPS Considerations • RF Power Supply • RF Cavity Field Error Signals • Reflected Power • RF Phase Error monitoring • RF – Beam phase monitoring? • RF Power Ramping (Amplitude modulation?) • Commissioning studies to determine acceptable losses verses RF parameters.

38. Ring Collimator MPS Inputs • Temperature sensors • Water Flow • Normal loss monitors? (Dynamic range OK?) • Motion – (Drop to lower beam power?) • Motion out of range (LVDT’s?) • Limit Switches

39. Extraction Kicker • “Fast and Slow” Kicker protection will be combined to give MPS one Fault output. (Charging supply status, Kicker Charged, Thyratron supply OK, Filament supply status, temp, flow, etc.) • One MPS signal per kicker. • Allow Operations to mask one kicker out. EPICS App. Does not allow more than one kicker to be masked • Kicker System needs 3 pulses from timing system, Start charge, Stop Charge, and Extract. • False firing – Abort ASAP or synchronous with beam gap. • Storage mode: If kickers are used to abort beam in storage mode additional timing signals are required, charging current goes through kicker magnets (1/e ~1sec), and kickers would need to be masked during storage.

41. High QA MPS Dump, TGT, Window • HQA – Time response, 32 msec (12 msec measured ) • Latched in PLC • Does not rely on Software • Machine Can Take Two Full Pulses • High QA configuration Controls • Hardware normally inaccessible • System Verification, routine testing • Documentation trail • Operational procedures • Redundancy –1 PLC, double up on sensors, use MPS-FPL for redundancy • Redundant shutdown devices

42. Control Net Layout

43. Personnel Protection System Linac zone HEBT Zone Ring Zone RTBT Zone Target Zone Machine Mode Selection Ion Source D-Plate L_DMP I_DMP RING E_DMP TGT Beam Mode Selection 7.5 kW 200 kW 2 MW 10 μsec 50 μsec 100 μsec 1 msec High QA PPS Inputs and Selection Switches

44. High QA Dump, Target PLC Remote Inputs • Target (or Dump) Status • Pressure, Temperature • Flow, Vacuum status • Power supply current monitor’s • Current and Voltage window comparators • Quads – Hi window, Dipoles, Hi and Off windows. • Steering corrector’s – Window (RTBT only) • HARP Status, P-P Permit Signal (Target only, Baseline) • Beam Current Monitor (Not in baseline, Hardware not chosen) • Co-Injection (Pulse-to-Pulse Species Modulation) ? • P-P Pulse Width verification • Beam Power, Integrated Beam Current • Beam Loss Monitor (2 per current monitor)

45. Injection Dump inputs

46. Target MPS Inputs

47. Power Supply Window monitors • Quad (Dipole) Magnet current compared with upper and lower limits, set in PLC Code. Limits determined by Accelerator Physics group. Magnet voltage used as redundant sensor. Commissioning: • With any input beam characteristics, quads limit peak current density at window and dump(tgt) below charge density threshold. • Upper and lower limits allow tunability from lowest LINAC energy to highest energy. • Beam size (density) verified by Wire Scanners and HARPS.

48. Power Supply Setting’s – Linac Dump(Data from Deepak)

49. Power Supply Setting’s – Linac Dump Window (Data from Deepak) • Problem in this case was percent of beam outside allowable area on dump)

50. Harp Commissioning • Target Harp can not operate 1 Yr. Pulse to Pulse • Target Harp is not retractable and is connected to window • Harp will probably survive a few months. • Operating Philosophy • Install set of redundant, retractable HARPS 180º upstream • Commission retractable HARPs with Window HARP • Set comparator limits on Optics • Once a year, verify system HARPS