GAS M&O meeting 20 January 2020

Present: Beatrice, Roberto, Fred, Patrick, Kacper, Andrea, Michal, Mara, Federico, Fabio, Sabino

Indico: https://indico.cern.ch/event/879657/

ALICE #2189

• MTR
  • Alarm in power supply: DC MCB trip —> Michal/Patrick to check
  • Start with standard gas mixture on Thursday and to add water to humidifier
  • No access full week 4

Reminder:

• • exhaust pressure regulation does not work
  • mixer pressure regulation does not work: Zimmerli not installed
• CPV
  • Probably water in pipes —> try to flush with N2

Reminder:

• • Start to reconnect the detectors but in one channel there is overpressure, probably coming from the pipe: LPh is investigating
• TPC
  • Still leak present, system is running in Ar
  • Problem of deltaP in TPC for the purifier due to metal frité —> LPh to solve
• TRD
  • Fred stop the second column

Reminder

• • Purifier: to review if keep the safety valve or the rupture disk
  • Purifier: safety valve at the input where we have Ar or Ar/H2 at high pressure —> LPh to check with safety
  • Alarm on power supply

ATLAS #2192

• CSC

Reminder:

• • After the power-cut there was not communication with PLC: damage of differential circuit breaker —> to repair
• MDT
  • To discuss procedure for pump changed
  • On-going work for pump
  • Safety valves under calibration
  • Add a second H2O sensor for the exhaust and use this one to regulate
  • For MDT a big PLC is needed: Michal ordered

Reminder:

• • In general: several problems with pressure sensor in MDT. Patrick said to add a resistance in the channel
• General
  • Power of bande chauffant —> Patrick/Kacper

CMS #2185

• RPC
  • barrel now in nominal flow
  • dummy chambers ready —> RPC people to install
  • iC4H10 MFC doesn’t work correctly —> to try to change to the second line
  • in 5 days we manage to have good gas mixture under gas recirculation with a flow in the mixer of 600 l/h
  • RE-3 #67 reading of flowcell is 50 l/h (but we are sending 200-300 l/h and the input pressure correspond to the one we had before) while RE-4 #68 is reading 260 l/h: Michal checked mapping, motherboard, calibration file and ELMBs and they are fine —> to investigate: Andrea to check flow with drycal
  • Federico to put in the elog the summary file of the pressure sensors of RPC
  • Fabio to put an elog of leak test with sniffer: at least 3 points with high leak rate
  • Reminder:
  • Missing quick manifold and flowcell in barrel +1 and +2
  • Swap of pipes in rack RE-1 (racks 61 and 65) and RPC 3.1 (racks 63 and 87)
  • Rack 85: to check if dummy chamber is installed, if yes to add pressure sensor connection
• DT

Reminder:

• • Difficult to re-start the gas system after power-cut —> to do some tests
  • Test for power cut and re-start for the exhaust line —> to do other tests
• CSC

Reminder:

• • Warning to set-up —> Beatrice/Michal/Roberto
• GEM

Reminder:

• • Flowcells problem in rack 61: ch 3, 5, 7, probably a leak in the connectors of the patch panel of GEM —> Mara to check with Daniel
• R134a recuperation
  • To start this week

LHCb #2190

• RICH1
  • last week: 1.5% of Air
  • stopped because the pressure in the loop was too high —> to do GC analysis
  • to change the MFC of CO2 in order to be able to check the CO2 injection: we have 30 l/h of CO2 —> ok to install to start and to have PID very low

Reminder

• • Re-fill with CO2 but we take 600 ppm because the pump took Air —> to think what it can be done to avoid Air intake at the re-start of the system
• RICH2

Reminder

• • To do a O2/N2 measurement before the stop —> Mara
• General
  • Interlock of Ar/H2 does not work —> Michal/Patrick to check
  • Crash of Auxiliary PLC —> to understand
    • Patrick explained how to re-start it and to have the file of the crash
    • Module Profibus and PLC can be touched only by Michal and PLC people
    • Also problem with Profibus cable/connector.module —> to understand where —> Patrick

PIQUET

• Nothing to report

GENERAL

• MFC calibration campaign preparation
  • All ok: only to swap the two lines of MWPC
• Mixer module maintenance presented by Sabino
  • Everything in dfs
  • Mixer not stable in exhaust: no problem, it has to be stable only when it is in run
  • In two weeks at least one mixer for experiment and it is very important to give comments
• R134a recuperation by Mara
  • Explication of the system and of first tests
  • To check DPT001, add DPT for iC4H10 buffer volume
  • Recuperation tried at 300 l/h
  • 10/15 small cycles to empty the second buffer volume
  • Time of regeneration of purifier 1 was too long and it was saturated: this happened with the software upgrade: every time there is an upgrade of software to check if recipes are saved —> Michal
  • Still some SF6 and iC4H10 in the output of R134a recuperation —> to check
  • Some problems to fix
• Flowcell summary by Mara
  • ATLAS TGC there is Iodine
  • Some flowcell have Ag other Platinum: which are the new one?
  • T understand what to do with the TGC flowcell: change flowcell with brand-new in one rack?