Access system global tests

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Access system global tests
LHCCWG January 15th 2007

• M. Gruwé

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Global tests

• Organization
• Organized by Silvia Grau and Pierre Ninin
• Performed by a big team of TS/CSE
• In collaboration with AB/OP (to help searching
  LHC, giving access, driving EIS-beam equipment,
  etc)
• From Monday 7th to Sunday 13th January

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Monday 7th Sunday 13th January

• Monday
• move the system from installation to
  operation configuration (Move from Myfare to
  Inside)
• Tuesday to Thursday
• closing and searching the whole LHC
• Thursday evening to Saturday evening
• tests
• Sunday
• move the system back to installation mode so
  that the access procedure is simplified (Move
  from Inside to Myfare)

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Closing and searching the LHC

• Tuesday morning
• point 8, including LHCb (about 5 hours)
• Tuesday afternoon
• points 7 and 6 (about 4 hours)
• Wednesday morning
• points 4 and 5, except CMS (about 5 hours)
• Wednesday afternoon
• points 2, 3 and 1.8, except ALICE (about 4 hours)
• Thursday morning
• point 1, except ATLAS (about 1 hour)
• Thursday afternoon
• ALICE, ATLAS and CMS (whole afternoon)

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Closing and searching the LHC

• Comments (I)
• In most cases, no real patrol of the various
  sectors but a simplified quick search
• All patrol boxes have been rearmed and sectors
  quickly searched.
• Patrol circuits described in various edms
  documents have not been used. These will have to
  be validated independently, later on.
• Plombage
• All emergency exit handles on all doors and
  access points have been provided with a
  plombage
• It is still possible to open the door by the
  standard way (unlock button)
• It is also still possible to open it with the
  emergency handle, but the plombage has a very
  dissuasive effect people think before acting!
• After the tests, the plombages have been left
  on most doors (to start educating people)

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Closing and searching the LHC

• Comments (II)
• Some people were still working in the sectors
  being searched
• This was foreseen (list of people was provided by
  the various groups having to make interventions).
  
• Situation not easy to handle, but in general
  people were cooperative and following
  instructions.
• Access to experiments allowed throughout the
  whole week
• Some grids have been removed around access points
  to allow access to experiments during the week.
• One guardian was placed next to each missing grid
  to control access to experimental zones.
• Overall, no interference with the tests except
  for one case one a person in Atlas opened
  (forced) a door between the Atlas cavern and the
  service area (search of the service area had to
  be redone) even though there was a big warning
  sign post.

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Closing and searching the LHC

• Duration
• Time foreseen 3 full days
• Was done faster than expected (but keep in mind
  it was a simplified quick search, not a real one)
• Unfortunately could not start the tests earlier
  than foreseen as it was agreed to search the
  experiments not earlier than Thursday afternoon

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Tests

• Tests in access mode
• One or more EIS-beam becomes unsafe
• Tests in beam mode
• One real AUG
• One door is forced
• Discordance between two signals

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Tests in access mode

• Initial state
• Whole LHC fully searched. Still in access mode
  (potentially some people in).
• All EIS-beam should be safe, so that it is
  impossible to circulate or even inject beam in
  LHC.
• Note EIS-beam are
• some power converters and corresponding 400V or
  18kV cells (should be off),
• some TEDs (should be in),
• electron stoppers (should be closed),
• etc

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Tests in access mode

• Test One EIS-beam becomes unsafe
• Result
• the system goes to access off
• Test Two EIS-beam become unsafe
• Result
• the system goes to access off
• and BIW (Beam Imminent Warning) sirens start
• Systematic tests done, for each EIS-beam, one
  after the other.
• Tests were successful.

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Tests in beam mode

• Initial state
• LHC fully searched and closed (leaving some
  people in, on purpose, for the tests)
• LHC access off (BIW sirens)
• Change to beam mode
• EIS-beam un-safe (power converters on, TEDs out,
  etc)
• From inside LHC force one door or one AUG
• As a consequence
• Beam mode is off
• Radiation veto is on
• All EIS-beam to safe position
• Signal sent to dump system
• Signal sent to BIC is false
• A sample of all types of doors tested inter-site
  doors, sector doors, end of zone doors,
  trapdoors, ventilation doors, access point (both
  PAD and MAD), etc
• At least two EIS-access per LHC site
• All inter-site doors
• One real AUG done in point 7

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Outcome of the tests (I)

• In general
• LASS (LHC Access Safety System) behaves as it
  should
• Human interface to LACS (LHC Access Control
  System) works fine but should be improved (slow
  response, could be more human friendly,
  occasional restart of the application)
• Some minor non-conformities to be fixed
• Few relays had to be changed, few problems solved
  on line
• One serious problem to be investigated,
  understood and resolved
• In one occasion non-detection of a missing key
  in a pad key distributor

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Outcome of the tests (II)

• Some behaviors remain to be understood
• First time LHC went to access off, BIW did start
  as expected, but then series of problems
  evacuation siren in point 6, fire alarm and ODH
  alarms in point 6, AUG in point 8. All false
  alarms, but resulting in fire-brigade
  interventions.
• Lesson learned
• Inform the fire-brigade before each test
• Instruct the firemen about how to enter the LHC
  without forcing doors (useful in this specific
  case when we know it is a false alarm)
• Some problems to drive the EIS-beam equipments
• In one occasion TEDs could not be moved. Still
  unclear why.
• In one occasion LASS saw TEDTI8 OUT (actually
  not IN) although it was IN. Is that a problem
  of end position contact?
• Electrical problems with two power converters
  (warm magnets in point 3 and 7) (to be discussed
  with equipment responsible)
• etc

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Outcome of the tests (III)

• Other comments
• The system tested was not in its full nominal
  configuration
• Some doors not included in the system
• to allow access to experimental areas during the
  tests
• some trapdoors not installed yet
• some ventilation doors not properly included
• SSA (System Safety Atlas) not ready and therefore
  not included in tests
• The new LASS console was not installed yet.
• Some more tests will have to be foreseen

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Outcome of the tests (IV)

• Other issues to be thought about and discussed
  with DSO
• Searching RF zones (including RF cavern)
  responsibilities? Procedure? Safety issues.
• BIW when two EIS-beam go unsafe should actually
  be evacuation siren rather than BIW
• Power converter and corresponding cell are
  currently considered as two independent EIS-beam
  should be considered as a single one, as they are
  not independent from each other
• OP should have a portable ODH detector available
  in the CCC

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Outcome of the tests (V)

• Excellent collaboration between TS-CSE and AB
• Overall a very successful and interesting week
• To be followed by DSO and OP acceptance tests