SNS Machine Protection System

1. SNS Machine Protection System EPICS Workshop April 27, 2005 Coles Sibley

2. Intro System overview Hardware summary Input Summary Software tools Configuration Control Tools needed for MPS

3. MPS Design Assumptions Four layers of protection! Hardware PLC Hardware / Software (Fast Protect Latched) Hardware / Software (Fast Protect Auto Reset) 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.

4. Layers of Protection 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. MPS PLC (~ 33 msec) Magnetic Field limit(s) verification Beam Dump monitoring

5. Machine Availability MODE masks are defined by MPS and Operations, not easily changed. Allows beam when invasive diagnostics are used only for SAFE beams. Easy OPI for verifying Mode Masks. Mode masks are applied pulse to pulse from timing system Allow easy bypass (Software Masking) for selected inputs Different rules for commissioning and operations Commissioning, FPAR devices can be masked Commissioning, FPL � subset of Quads can be masked, all dipoles and rest of quads need ASD Operations approval.

6. Machine / Beam Mode Definitions Machine Modes MEBT Beam Stop CCL Beam Stop Linac Dump Injection Dump Ring Extraction Dump Target Beam Modes Diagnostics (10 usec) Diagnostics (50 usec) Diagnostics (100 usec) Full Pulse Width (1 msec) Full Power (Depends on Dump)

7. MPS Timing System checks RTDL Heartbeat (PCI Clock) Event link heartbeat Driver � IOC heartbeat Hardware Configuration file checks against actual HW settings Machine / beam mode (< 3.3e-10 probability of undetected fault) 8 bit CRC (1/256) 8b bits encoded in 24 bit frame for single bit errors 24 bit CRC on all frames (1/16777215) Mode Masks mask + /mask>>8 (single bit upset errors) Software verification of masks (Configuration control) Checksum of masks (File integrity) Cable Status monitored

8. MPS Hardware Technobox PMC reconfigurable IO card 10K70 Altera (20k200 newer) Up to 5 per IOC with PMC_Span, 16 inputs each

9. MPS PMC Module (Also nice generic digital IO module)

10. MPS Fast Protect System Layout Master oscillator signal to carrier links Input Links will be discussed Add estimated time rangeMaster oscillator signal to carrier links Input Links will be discussed Add estimated time range

11. MPS Input Summary (August 5005)

12. MPS � PLC Control Net Layout

13. PLC Remote Inputs Machine made, Beam Mode selection Emergency Crash Trigger Control sanity checks Timing System handshakes Target (or Dump) Status Pressure, Temperature Flow, Vacuum status Power supply current monitor�s Quads � Hi window, Dipoles, Hi and Off windows. Steering corrector�s � Window (RTBT only)

14. Injection Dump inputs Beam Current Monitor (Not in baseline, Hardware chosen) P-P Pulse Width verification Beam Power, Integrated Beam Current No direct current density or beam position monitors on dump windows or target

15. Run Permit (Software) Layers Configuration Control Mode masks SW masks EPICS db�s Archiver files Alarm Handler (?) Timing System db�s Post Mortem First fault Waveform viewer Software monitoring PS�s Field RF, Phase and amplitude BLM HV Selected set point limits Timing System pattern generator Integrated Beam Loss (software MPS trip)

16. MPS Applications First hit and total trips entered every day at midnight MPS First Hit stats since Sep 19, 2004 00:00:00RFQ_LLRF:HPM1:FPAR_Src_chan_status, counts = 2806DTL_LLRF:HPM5:FPAR_CCL_BS_chan_status, counts = 2176DTL_LLRF:HPM6:FPAR_CCL_BS_chan_status, counts = 755CCL_MPS:FPAR_Sublink04D:FPAR_CCL_BS_chan_status, counts = 624 Noise was initially a big problem. Noise reduction, filters, fiber installations have mostly eliminated the problem.

17. MPS Applications Input Status Summary Shows input status and consequences of changing beam modes or machine modes. Mode Mask Verification Replaces spreadsheet, paper and pencil Replaces tedious task of verifying 35 modes per input * 350 inputs = 12250 individual checks Automated Verification (in progress) Check inputs Trip and verify MPS Reset, turn back on Generate report to e-log

18. MPS Bypass Request

19. Software tools needed 3D Waveform viewers BLM waveform vs. time or accelerator location Scope Application (Correlated waveforms) RF vs BLM waveforms Injection / Extraction kickers vs BLM BCM vs. BLM Post Mortem Tools First fault BLM loss model vs component BLM waveform signatures (Archive waveform viewer) Fast vs Off Energy vs Halo MAID (Maximum allowable intra pulse difference) � Full Power operation Verifies beam to target parameters acceptable before allowing next pulse (or as fast as possible) Beam Scheduler / pattern generator