UITF Conduct of Operations Review UITF Review 3

UITF Conduct of Operations Review UITF Review #3 Machine Protection System Matt Poelker Wednesday, April 24, 2019

UITF Machine Protection System - what will it protect? • Protect the QCM (we also call it “the booster”) • Protect against beam loss and burn-through, maintain ultrahigh vacuum • Protect viewers (this is a software interlock – Not a fast shutdown node, FSD) • Protect magnets, ensure proper field for beam transport: comparator interlock, water flow or klixon interlocks • Protect RF beamline components: vacuum and water flow interlocks • Protect cups, apertures and dumps: water flow interlocks (and limit beam current via “operational restriction”) • Protect the experiment, e. g. , HDIce (mostly, this means putting the beam where it is supposed to go, limit beam current if necessary, protect against mis-steered beam) UITF Conduct of Operations Review - MPS 2

Hardware configuration • Valves OPEN only when vacuum deemed acceptable • Current limiting resistors in series with magnets • Water flow interlocks at cups, dumps and apertures • Window comparators on dipoles and gun HV • Viewers inserted only when laser in pulsed-mode • Water flow interlocks at buncher and chopper cavities, RF applied to chopper and buncher only when vacuum reads “good” • Helium liquid level interlocked to klystron high power RF UITF Conduct of Operations Review - MPS 3

FSD Input Signals • An FSD trip will shutter laser and sometimes close all valves • BLMs will shutter laser: CEBAF-style BLM modules • RF field control chassis with CEBAF-style FSD signals • Vacuum FSD signals from QCM, helium liquid level interlocked to klystron control panel • All beamline ion pumps ganged together, close laser shutter and close all pneumatic valves when pressure exceeds a setpoint • Window comparators using 16 bit ADC cards designed by EES • HDice “off target” detector (it will look like a BLM) UITF Conduct of Operations Review - MPS 4

What happens when there’s an FSD signal is triggered? • UITF Machine Protection －Ion pump values too high, then can’t OPEN valves. Close valves when ion pump current rises too high －Chopper/Buncher Ion Pump current too high, can’t turn ON chopper/buncher RF, trip OFF the rf supplies －Viewer IN, allow only Viewer Limited beam －Water flow through apertures, cups and dumps OK －BLMs trip OFF beam, close laser shutter. These can be maskable so we can tune up in Tune Mode －Dipole window comparator on 15 degree ben magnet: no Laser when bend magnet current wrong －Gun HV window comparator, no laser when gun HV set wrong UITF Conduct of Operations Review - MPS 5

Similar to CEBAF • Safety System Group BLM chassis, x 2 units • New LLRF control boards, aka Field Control Chassis • Cryo and SRF signals from QCM • Window comparators using 16 bit ADC cards designed by EES • FSD signals summed using VME boards with 12 input channels each • FSD signals transmitted via fiber at 5 MHz • SCAM to create low duty factor modes • CEBAF style pockel-cell tune mode generator: RTP cell with <250 ns response time, backed by shutter that closes 5 -10 ms later UITF Conduct of Operations Review - MPS 6

BLM locations UITF Conduct of Operations Review - MPS 7

Me. V beamline (Songsheets = UED) UITF Conduct of Operations Review - MPS 8