Difference between revisions of "October 27, 2020 - Magnetic field mapping and characterization meeting"

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(Created page with "*Media:Magnetic field mapping meeting Oct 27 2020.pptx '''Hardware:''' * Use new SCE 20A/75V PS for measurements. This is the same type of PS that will be used for o...")
 
 
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   *  Software will provide EPICS controls and hysteresis ramp loops
 
   *  Software will provide EPICS controls and hysteresis ramp loops
 
   *  Label and wire coil leads to ensure positive current produces positive B field per convention
 
   *  Label and wire coil leads to ensure positive current produces positive B field per convention
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   *  PS limits for Hysteresis curve: 20A at 1A/s, but measurements done at +/- 19.9A
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   *  Hysteresis limits: +/- 19.9A
  
 
'''Field mapping:'''
 
'''Field mapping:'''
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'''CED field map'''
 
'''CED field map'''
  
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   *  EPICS hysteresis cycle ending at +19.9 A.  Measure B(I) at center of magnet at 19.9A, then decrement by 0.9A to 19A, then 1 A increments until -19 A reached.  Final reading -19.9A.  All without further hysteresis loops.  Finally, set to zero A and EPICS hysteresis cycle.   
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   *  Measure B vs. I at center of magnet using the EPICS hysteresis cycle at the beginning then top down through currents.   
  
 
'''Other measurements:'''
 
'''Other measurements:'''
  
 
   *  V vs I resistance and inductance.
 
   *  V vs I resistance and inductance.

Latest revision as of 15:20, 27 October 2020

Hardware: 

 *   Use new SCE 20A/75V PS for measurements. This is the same type of PS that will be used for oparations
 *   DC power will install new SCE PS in magnet test ~10/29/20
 *   Software will provide EPICS controls and hysteresis ramp loops
 *   Label and wire coil leads to ensure positive current produces positive B field per convention
 *   Hysteresis limits: +/- 19.9A

Field mapping: 

 *   Hall probe step size 2 mm
 *   On axis values z=[-25,25] cm
 *   Background: measure z=[-30,30] cm. First run the probe in this range w/o the magnet. Then place the magnet for measurements and do a full map at 0 A after hysteresis at 0A . Finally subtract from each value.
 *   Off axis values: limited by 15 mm diameter nickel endplates hole and 6 mm square hall probe. Measure z=[-25,25] cm once at 18A and as far as these limitations allow in +X,-X,+Y,-Y and record X,Y positions for comparing with models.
 *   Measure at +/-19.9A, +/- 15A, +/- 10A, +/-5A and 0A.

CED field map 

 *   Measure B vs. I  at center of magnet using the EPICS hysteresis cycle at the beginning then top down through currents.

Other measurements: 

 *   V vs I resistance and inductance.
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