-- MarkWard - 23 Jan 2017


  • Reorganised electronics cabinet to lift potentially delicate electronics off of the floor.
    • Pumping station and penning gauge readout now on a new bottom shelf, interactions with these objects are minimal
    • NIM crate has been moved to the top, this keeps loose cables away from peoples feet!
  • During testing of several power supplies for the Anode, the NIM crate is found to have a faulty -24 volt rail. All other rails appear to be fine within norms, but -24 volt rail reads as approximately 14 volts. This causes problems with anything using -24V and in the case of the power supplies tested, severly limits their output to roughly 300V.
  • Found a power supply with an independant power source, bringing the total to two
  • Found a leak on the atmospheric pressure gauge, it was a little bit more than hand tight, with a single loop of teflon.
  • Leak rate reduced by an order of magnitude after fix, gauge readings appear slightly different during pump down, the gauge looks ok down to approximately 40torr rather than 80. Issue likely being the leak causing local pressure
  • 10^4 range leaks are still pretty poor, BUT can actually indicate virtual leaks or heavy out gassing. Rate of rise measurements become very difficult unless a vessel has been previously baked or pumped down for a long period
  • Less worried the vessel is leaking.
  • Leak_rate.png


  • Floor load testing still to be determined
    • Hole in the floor has been filled with what looks like concrete
    • Items from the hallway have been moved into the lab, couple of crates and boxes plus tables... I suspect these are not perminent features, and were moved for the open day tour. Will confirm with Andy.
  • Items to Sam at Cryovac;
    • Requested information regarding burst disk part numbers so i can look at tollerances (how Close to 5 bar can we go)
      • Need to figure what type of disk it will be could be a -10% to 0% range, meaning the max we can safely go could be 4.5bar, but equally it could be a range -3 to +6% (depends on design) meaning 4.85 bar...
    • Requested information regarding part numbers of components such as regulators
    • Requested information regarding a removable line between the gas manifold and the gas inlet to the chamber. (for later additions)
    • Requested information regarding full platform elivation (hand cranked or electrical) for the chamber such that it can be built for 1.3m height but aligned to the beam at 1.7, parrallel to this (Zach) investigate options for elivation changes at CERN
      • Looks like we have a solution of using 800mm and 400mm blocks to build a platform.
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Topic revision: r1 - 23 Jan 2017 - MarkWard

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