With Terrence and Hirata-san.

The hightlights are:

• Today the temperature in the clean booth was 24 ºC, which is what we had asked (entry 7420), therefore, I removed some mass from the top of the keystone in order to have it at ~ 0 µm height. The height was - 24 µm with 521 grams.
• The calibration is shown in the Excel spreadsheet attached.
• I considered the polarity of the stepper as incorrect: positive number of steps produced a negative displacement in the LVDT (opposite to SR2 and SR3).
• In order to correct this we exchanged pins 1 and 6 in the connector but the stepper didn't work at all.
• We decided to exchange the pins back to their original configuration, but we had to use channel 3 instead. Appenrently we ruined a channel.
• After the calibration we decided to remove mass from the keystone in order to accomodate the bouyancy correction. This will happen tomorrow and I will also check the changes to the results reported here.
• Stepper motor:
  • Maximum: 1,600,000 steps, top of carriage at 44.45 mm from reference (top of the Al plate whic is on top of the stepper motor box). This is the lower end of range.
  • Minumum: -1,600,000 steps, carriage at 105.25 mm from reference.
  • Total range: 3,200,000 steps.
  • Mid-range position: zero steps,carriage at 74.85 mm from reference.
• Fishing rod effect on keystone:
  • Maximum: 626 µm.
  • Minimum: - 865 626 µm.
  • Total range: 1.491 mm.
• EPICS channel name: K1:STEPPER_SRM_GAS
• IP address: 10.68.150.57
• Channels:
  • #0: BF
  • #1: F1
  • #2: Does not work.
  • #3: F0