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
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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
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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
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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
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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