dale don dale
Transcription
dale don dale
Canada’s national laboratory for particle and nuclear physics Laboratoire national canadien pour la recherche en physique nucléaire et en physique des particules TRIUMF 520MeV Cyclotron Machine Protection Don Dale Manager, Electronics and Controls Accelerating Science for Canada Un accélérateur de la démarche scientifique canadienne Owned and operated as a joint venture by a consortium of Canadian universities via a contribution through the National Research Council Canada Propriété d’un consortium d’universités canadiennes, géré en co-entreprise à partir d’une contribution administrée par le Conseil national de recherches Canada 520MeV Machine MPS • Central Safety System (CSS) • 100-200mSec trip range • Two devices to define machine off • Beamstops in horizontal section (used to be in vertical section), but changed to beamstops in horizontal section for ease of access) • Chains of devices • Vacuum Valves – one summary contact closure to CSS for OK • Beam Optics – summary OK contact from reed switches in magnets • Target Protect Monitor – OK contact from Diagnostic Systems • Thermocouple Temperature monitors – summary OK • Spill Monitors – • Extraction Probe foil current - March 5,6 2014 e-Linac Machine Protection System Architecture 17 520MeV Machine MPS • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Signals Which if Lost Generate `safety’ Machine Protect Trips If Central Safety System (CSS) thinks beam is on (Safety Machine Protect Trip drives in two beamstops in accessible horizontal section of injection beamline.) Water Cooled Probe Cooling OK Periscopes Out Tank Spill Monitor HV OK Inflector Up RF Resonators Latched Tank Pressure < Atmosphere but > 10**-5 Vault Crane @ position to run beam Remote Handling Shield Door Sealed BL1V Magnets Ready BL1V Valves Open (1VVR1, 1VVF2, 1VVA4) BL1A Magnets Ready BL1A Valves Open (1AVA6, 1AVA8) BL1A T1 Ready BL1A T2 Ready BL1A Collimator Ready BL1A T1 Protect OK BL1A T2 Protect OK BL1A TNF Protect OK BL1A TNF Ready BL1A Irradiation Facility OK M15 Permanent Magnet Flow OK BL1B Magnets Ready BL1B Valves Open (1BVA6) BL2AV Magnets Ready BL2AV Valves Open (2AVVR1, 2AVVA2) BL2A Magnets Ready BL2A Valves Open (2AVA4) BL2A2 and 2A3 Magnets Ready March 5,6 2014 • • • • • • • • • • • • • BL2A2 Target Area Ready BL2A2 Target OK BL2A2 Target Protect OK BL2A2 Dump OK BL2A3 Target Area Ready BL2A3 Target OK BL2A3 Target Protect OK BL2A3 Dump BL2C Magnets Ready BL2C Valves Open (2CVVR1, 2CVVF2) BL2C Line 1 OK BL2C Line 4 OK BL2C Line 7 OK e-Linac Machine Protection System Architecture 18 520MeV Machine MPS Central Safety System • CAMAC based • Processor upgraded over the years • • • • Kinetic Systems TRIUMF designed and built TRIMAC CES Starburst (PDP 11/70 in CAMAC) Embedded X86 PC by ECROSSER (current) • Using a USB – CAMAC controller from Wiener • This allowed upgrading without changes to the field wiring March 5,6 2014 e-Linac Machine Protection System Architecture 19 Recent Incident HE1 High Energy Probe • • • • • 7 vertically stacked fingers Probe head is lowered into beam plane Probe moves radially for tuning Parked out of beam when running high current Current on the Fingers are summed and a Control System interlock stops beam in injection line if current exceeded • Probe cover grounded (cannot read current) March 5,6 2014 e-Linac Machine Protection System Architecture 20 Incident • Probe motor was driven and position readback changed but the probe never reached a limit and the measured beam current never changed • Probe head raised and the lowering drive signal defeated (April 19) • Ok to run - probe is out of beam plane • An indication that the Probe was no longer at the upper limit resulted in the lowering actuator being physically clamped on the cyclotron lid (April 30) • BL1A current increased – HE1 beam trips (10 in July) • No indicators of abnormal beam loss – cyclotron transmission was 65% - later determined that improvements made in the last maintenance increased transmission to 70% • Diagnostics using the HE2 probe in August indicated a 5% loss at around 190 inches • More HE1 current trips – trip level raised • HE1 current readbacks could be changed by adjusting trim coils • Beam off for maintenance January March 5,6 2014 e-Linac Machine Protection System Architecture 21 Post-Mortem Melting March 5,6 2014 e-Linac Machine Protection System Architecture 22 Post-Mortem • Beam was hitting the lower cover • Secondary electrons caused the overcurrent trips Probe head drive fails at worst location 190inches Roll pins added March 5,6 2014 e-Linac Machine Protection System Architecture 23 Canada’s national laboratory for particle and nuclear physics Laboratoire national canadien pour la recherche en physique nucléaire et en physique des particules Thank you! Merci Owned and operated as a joint venture by a consortium of Canadian universities via a contribution through the National Research Council Canada Propriété d’un consortium d’universités canadiennes, géré en co-entreprise à partir d’une contribution administrée par le Conseil national de recherches Canada TRIUMF: Alberta | British Columbia | Calgary Carleton | Guelph | Manitoba | McMaster Montréal | Northern British Columbia | Queen’s Regina | Saint Mary’s | Simon Fraser | Toronto Victoria | Winnipeg | York