1. Use Cases - Cryo Services Speaker: Klaus Barth on behalf of TE/CRG
TETRA Forum
Wednesday 09 March 2011 from 14:00 to 17:05 (Europe/Zurich) at CERN ( Council Chamber )

2. Outline LHC Accelerator and Detector Cryogenics Service
accelerator cryogenics operation
detector cryogenics operation
Cryogenics services related to activities for other detectors and test facilities
Outlook/Conclusion

3. Layout of LHC Accelerator Cryogenics
S. Claudet
LHC Cryogenic system

4. LHC Accelerator Cryogenics Subsystems

5. How are alarms originated ?
accelerator cryogenics operation
How are alarms originated ?
Global overview, 3x8 alarms only => 24 alarms sent through cern standard infra channels
W: Warning - RC: Reduced Capacity - FS: Full Stop
4 points - 8 sectors, organised by cryo sub-system
Status of alarms per sub-system
Thousands of individual alarms grouped with possibility to mask each one depending on operation mode or status (nominal/techstop) to end up with only 24 potential alarms transmitted via Laser to Ti, and automatic call on cern GSMs via Mobicall
SC - 09Mar'11
Review for Alarms handling

6. How do we deal with alarms ?
Normal case:
Taking alarm in consideration, early diagnostic
Confirming to Ti that alarm is being treated
Taking action that could lead to sending people (1 or 2) on site
Once treated, confirming to Ti that operation is back to nominal
Abnormal case: Easy thanks to shift crew 11months/year, done at few occasions
In case of network/Laser issue, visual or verbal information Cryo shift / Ti shift as we sit next to each other in CCC …
We can always check our supervision panels with flashing alarms !!!
Not against using a new system, but happy with present situation, and very low probability to have a GSM issue during an intervention on site putting people safety in delicate situation!
SC - 09Mar'11
Review for Alarms handling

7. LHC Detectors (CMS/ATLAS) cryogenics operation
Magnet configuration comprises: thin superconducting solenoid surrounding the
inner-detector and three large superconducting toroids (one barrel and two end-caps)
High granularity liquid-argon (LAr) electromagnetic sampling calorimeters, LAr technology is also used for the hadronic calorimeters

8. External and proximity cryogenics for the ATLAS LAr calorimeters.

9. External and proximity cryogenics for the ATLAS magnet system

10. Cryogenics services related to activities for other detectors and test facilities
North Area fixed target experiment cryogenics (EHN1/EHN2/EHN3): NA61, NA62 (LKr calorimeter), H8 + RD5 test beams
CAST (LHC-P8) cryogenics
SC Magnet and Cable Test SM18 and Meyrin Site bldg. 163
Cryolab Central LHe distribution Meyrin Site bldg. 165

11. Organization of the cryogenics operation service CRG-OD
Dedicated CERN operation team of 5 technicians (on-call) for LHC detector cryogenics
FSU operation team (on-call) with CERN expert technician and engineer support for cryogenics related to activities at North Area, CAST, Meyrin Site bldg. 163/165
FSU operation team (on-call) with CERN expert technician and engineer support for cryogenics at SM18 test facility
Alarming (grouped and prioritized) is done via MOBICALL and the CCC-TI shift team. Works very reliable.
Interventions of cryogenics operation team are coordinated via CCC-TI and the experiment control rooms of ATLAS/CMS
Tech. expert support (mechanics, instrumentation, control system) can be called in by operation teams if required (on-call).

12. Outlook/Conclusion
The cryogenics alarming service works well and reliable, based on several components (cryo shifter, CCC-TI, MOBICALL)
TETRAS could be a complementary system for cryogenic services for replacing/standardising existing safety devices/procedures (ODH, “Homme Mort”)
TETRAS could be complementary communication system giving fire brigade, CCC-TI direct access to information from cryo operation.