Linac Test Area Instrumentation Update

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Linac Test AreaInstrumentation Update

• M. Haney, D. Errede,Z. Conway
• University of Illinois at Urbana-Champaign
• 14 June 2002

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Instrumentation

• Need safe solution for instrumenting the LH2
  absorber in the LTA
• Prudent to accommodate MICEand European safety
  considerations
• i.e. do it right the first time

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Primary Objective - Safety

• Intrinsic safety, if possible
• Less than 1 watt (per channel?)
• Good idea for Fermi required for Europe
• Gas-purged enclosure, if necessary
• 19 rack, 40U tall

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Signals inside (the cryostat)

• 12 (cryo) temperatures
• readout via GPIB LabView (PC)
• 25(ish) 4-wire bolometry strips
• Multiple fibers
• FISO strain gages
• Laser occlusion?
• Simple spark detectors
• (light pipe to photodiode)

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(more) Signals inside

• USB (4 wires, and shield) for CCD camera
• via PC
• Piezo vibration sensor
• via (16 chan/12 bit) ADC and LabView (PC)
• Local (64 chan/16 bit) IRM channels
• via LabView (see last slide)
• MICE channels (?)
• placeholder for the future

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Signals outside

• Many voltages, currents, temperatures, pressures
• magnets, beam position monitors, etc.
• Most available from ACNET or local IRM
• via LabView (see last slide)
• or Cyro-PLC
• and Intellution

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Two Possibilities (1)

• Intrinsically safe

Hazard Safe
Sealed Conduit(s)
Barrier(s)
ACNET
IRM
Cryo(temp)
FISO
PC w/32 chan ADC
network
power
Intrinsically safe signal conditioners and
transmitters
UPS
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Two Possibilities (2)

• Gas-purged box

Hazard Safe
Barrier(s)
Sealed Conduit(s)
ACNET
IRM
Cryo(temp)
FISO
PC w/32 chan ADC
network
power
UPS
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(basic) Barrier
fuse
Power Signal
safe circuit
Return
Ground
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This Summer Z. Conway

• LabView interface
• GPIB
• ADC
• IRM

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Open Issues

• Local signal condition vs Purged box
• Common mode concerns (noise from magnets)
• Especially surge currents on start/stop
• Long wires!
• 2-wire vs 4-wire solutions
• Shielding and noise sensitivity in general
• Cable plant size concern
• (already 200 wires, not including shielding)

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Open Issues (2)

• LabView vs C
• to read ACNET data (mostly, IRMs outside of the
  experiment)
• Remote control of PC
• Citrix ICA, PCAnyWhere, etc.
• LabView web-remote instrumentation
• KVM?