Download CLAS12 Drift Chambers Utilities and Support Systems

CLAS12 Drift Chambers
Utilities and Support Systems
George Jacobs
Jefferson Lab
Hall B 12 GeV Upgrade Drift Chamber Review
Jefferson Lab
March 6- 8, 2007
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
Drift Chamber Utilities and Support Systems
The Drift Chamber Gas (DCGAS), Drift Chamber Low Voltage (DCLV), and Drift Chamber High Voltage (DCHV)
systems are already in place with mature control, monitoring, and alarm subsystems.
These systems will be USED in CLAS12 with minor modifications and upgrades.
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS DC Gas System Overview
System consists of 2 separate mixing and storage systems
System originally designed to mix 2 different gas mixtures
Original design for Argon-Ethane and Helium-Ethane
Current mix is 10% CO2, 90% Argon in both
Twin systems also provides redundancy
System consists of 3 separate supply and pressure control systems
System was originally designed to recirculate gas
Current system exhausts to atmosphere
Each region is separately monitored for contaminants
System has active and passive safety controls
Active controls isolate the detectors in case of high or low pressure
Passive high capacity pressure relief bubblers attached to detector exhausts
System designed to Fail Safe on loss of power
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS DC Gas – Mixing and Storage
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS DC Gas Controls
MKS MFC based mixing system
Panametrics TCU monitor the mix
Calibration gases are used to match the mix
Panametric moisture image monitors H2O
Teledyne trace O2 transmitters monitor O2
MKS based pressure controls for DC
Magnahelic based active safety system
Bubbler based passive safety reliefs
Fail Safe design on loss of power
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
Hall B Gas Shed
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS DC Gas Flow Paths
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS DC Gas Controls
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS DC Gas Hall Hardware
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS DC Gas Volume Exchange Rate
Current System Capacities
R1 - 15 minutes at maximum flow rate (48 slm)
R1 - 30 minutes standard flow (24 slm)
R2 - 1.5 hours at maximum flow rate (90 slm)
R2 – 2.25 hours at standard flow (60 slm)
R3 – 3 hours at maximum flow rate (120 slm)
R3 – 5 hours at standard flow (72 slm)
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS DC Gas EPICS Interface
EPICS
DCGAS
GUI
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS12 DC Gas Upgrade
Complete System will be reused as is with minor plumbing mods required in the Hall
1) Relocate supply and exhaust manifolds in Hall
2) Run new piping to the manifolds from the hall gas panel
3) Run new piping from manifolds to the individual detectors in the Hall
4) Relocate the over and under pressure protection bubbler units
New System Operating Parameters
- CLAS12 gas volumes will be less than the current detectors for R2 and R3
- CLAS12 volume exchange rate for R2 and R3 will increase
- CLAS12 volume exchange rate will decrease for R1
- CLAS12 R1 volume exchange time will increase to 1.25 hours
- Gas flow capacity can be increased by adding pumps and/or adding parallel control valves
Disconnect the gas lines from the old detectors and connect them to the new ones
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS DC Low Voltage
DCLV supplies power to on chamber pre-amps
HP6651 DC power supply rated at 8vdc 50amps
LabView GUI based monitor and alarm system
Very dependable Power supplies with only 1 crate failure
in the 10+ years of operation
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS DC Low Voltage Monitoring System
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS12 DC Low Voltage Upgrade
The HP power supplies and GPIB monitoring equipment will be reused as is.
No software changes are required for the LabView based monitor and alarm systems.
Decrease channels per sector to 1344 reducing current to ~20 amps per sector
Increase Segmentation to 1 fuse per 32 channels or 42 fuses per sector
Reduce current per segment or fuse to <0.5 amps
R3 DCLV is ready but R1 and R2 DCLV will require new distribution fuse boxes
CLAS 12 conversion will require new DCLV cable runs from the fuse boxs to the patch
panels on each sector.
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS DCHV – Drift Chamber High Voltage
DCHV provides HV to the DC
CLAS DCHV System consists of 3 CAEN System 527 HV Mainframes.
System is controlled via a CAEN Network VME card using the DCHV GUI
There are 10 HV modules per crate, 24 Channels per module, 40 micro-amps per channel
16 +HV and 16 -HV channels are available for each individual sector
DCHV GUI allows for easy operations for ramping up and down the DCHV
DCHV GUI permits operation of single sector, region, or channels
DCHV GUI permits adjusting voltages, trip set points, ramp rates, etc
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS DCHV Control GUI
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS DCHV Groups
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS12 DCHV – High Voltage Upgrade
R2 and R3 HV distribution panels can be used as is with new labels
R1 requires new HV distribution panels to segment the HV channels
Requires CAEN crate reprogramming for new group configurations
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS12 Region I HV Patch Panel
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
CLAS12 Region I HV Patch Panel
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007
Summary
 The required utilities, DCGAS, DCLV, and DCHV are already in place
and require minimal modifications for the CLAS12 upgrade.
 Systems have been refined and optimized over a decade of operation.
 Controls and alarm systems are mature and have already been debugged.
 The technical staff has many years of experience with these systems.
 Trained system experts rotate for 24-7 on call support for these systems.
Thomas Jefferson National Accelerator Facility
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Hall B Drift Chambers Review, March 2007