UITF Meeting - January 19, 2018
As you know Carlos is taking over the day to day ops of UITF, thanks Carlos! Here's my summary of where we left the UITF MPS/UITF stuff, or at least what I found on my PC. The spreadsheet is really keV specific, because it's the only beamline that exists now. I am not sure how the MPS/FSD changes as the UITF beamline grows to include the QCM and then MeV beamlines. I don't think our plan will change much as we grow beamline, but maybe we add more MPS/FSD trip nodes, I don't know. I lost steam and did not add the actual epics names of the various signals....
If you think it's worth a meeting to review details, I am happy to schedule one.
Basically, we imagine three destinations: 1) beam to anywhere in the keV section, 2) beam through QCM at MeV energy to a straight ahead dump (the beamline we hope to build this year), and 3) beam at MeV through a dedicated beamline to a "user" or experiment, like HDIce.
Viewers and RF controls are shown on the schematic below but per Scott's guidance, but these items are not considered part of the UITF MPS. I include them on the schematic for my edification. Inserting a viewer takes beam to Viewer Limited mode via the SCAM and laser interface chassis. Curt and Rick have "machine protection" as part of the RF field control chassis, for example, no RF gets applied when water flow is not present, or when vacuum is bad. So machine protection by my definition but not part of our UITF MPS/FSD system by Scott's definition, i.e., an RF issue won't turn OFF beam.
UITF MPS consists of only four "things" that will turn OFF beam by closing a laser shutter: 1) water flow must be present to cups, apertures and dumps, 2) the BLMs from the safety system group, 3) vacuum must be acceptable (we define acceptable via epics), more on this below, and 4) we think we want two window comparators, one for the dipole magnet, and one for the Gun HV setpoint. Keith and John had ideas how to implement the window comparators. Not needed righ now but we definitely want them eventually.
For item#3, vacuum, here's how this plays out. The UHV supplies have an interlock output, and all these signals go to a box made by Jim Kortze. If an ion pump sends a "bad vacuum" signal to Jim's vacuum box, it closes valves. It is the act of closing of valves that sends an FSD trip to the laser shutter. So an FSD trip occurs when there's bad vacuum, but it's the closed valve that actually triggers the FSD.
Great progress in 2018! keep it going,