Agenda/Minutes on 2020/12/25

Zoom Meeting

CRY+VIS Interface Meeting

13:30-

Participants:

Post O3 Upgrade portal

• Schedule: Connection of ITMX after 1/12(1/13?). Chamber closing of IXC from 2/8. Update of schedule for ITMY.
• Flow chart: Two-step commissioning in vacuum.
• Acceptance check items: Making the document for cryo-payload.
• Jig for FC painting: Ordered.

• PF actuator: Measurement of coefficients --> calculation of the noise (by the end of Jan.).

VIS Meeting

14:00-

Participants:

Progress report

General

Type-A

• Preparation for IXV.
  • Blade bending jig was moved to the IXV booth.
  • LVDT coils were assembled onto the ACCs.
  • Horiuchi-san (MPC) will join to Type-A team from 1/5.

Type-B

Albums

• BS remedying work after O3

• SR2 remedying work after O3

• SR3 remedying work after O3

• SRM remedying work after O3

Week of the 14th of December

• Yano-san repaired a damaged thread in a BS LVDT component. He also compiled the bill is screws.
• Hirata-san and Yano-san went to wash the BS LVDT components ot the University of Toyama.
  • The components were brought back to the tunnel on Friday.
  • The plastic box was opened until Monday to let the components warm up to room temperature and thus avoid condensation.

  • Yano-san finished writing a nice procedure to assemble the LVDTs.

• After receiving and washing new screws, we mounted the new lighter F0 keystone assembly top disc in SR3 (klog 15664). We removed 96 grams to compensate for the extra weight of the F0 yaw stepper motor mechanism.

• I finished writing the procedue for adjustting ballas mass in SR3. Hirata-san and Yano-san read it and they had comments.
• The temperature in BS area this week was still high (around 23.6 degrees). Yokozawa-san had misread my message and he thought such temperature was the one requested. Now he is aware of the temperature we want (close to 23.1 degrees).

• Despite the temperature being high, we added ballast mass on top of BS BF in order to assess how easy or hard was going to be to keep the BF current balance (klog 15651 and comments):

  • As planed, we put equal amounts of mass on geometrically opposite places: 66 grams in each place.
  • It worked well in the sense that we didn't disturb the aligmment of the IMR and OSEMs. The largest change was -41 urad in IM-R, which is rather small for this type of adjustment.
  • Transfer function measurements showed a healthy system.
  • F1 fishing rod had been put in mid-range beforehand and the additional ballast moved keystone position down by 560 um to 423 um. We will need to add more ballast later because we aim to 212 um.
  • The yaw measured by the oplev changed also, but this is due to the change in F1 height and coupling with cables.

Week of the 21st of December

• On Monday we receive the BS IP LVDT yokes:
  • They were cleaned during 5 minuted in the ultrasonic bath with acetone in ordert to remove residual rust, likely coming out from threaded holes.
  • We assembled completely two LVDT-actuator units; the other one was partially aseembled because we only have two jigs. After installing the first one we will finish the assemby of the third one.
  • After assembly we checked the resistances of the coils to make sure there was no damage.
• We finished the assembly and installtion of the BS limit switches for the IP horizontal fishing rods.
  • We attached extensions to some of the cables.
  • Because of the lack of cable clamps in the designed we used inserted M8 vented SDC screws in nearby holes and used them as poles. We tied cables to them using kapton coated wire.
  • We tested the switches manually and checked the medm screen gave the correct signal.
• In SRM we corrected the polarity of the F0 FR stepper motor.
  • There was some troubleshooting to do: a cable broke at the attachment point to a pin (pin 2) and we fixed it.
  • Using a spare stepper motor we checked the health of the unused channels in the SRM GAS Filter driver: two out of three work.

Type-Bp

Type-C

Controls

Electronics

Towards O4

• Type-B remedy work is on going.
• Remedy work in IXV will start on 1/5.
• Schedule.

  • Chart

• Procedure documents.

  • Type-A tower installation

  • Limit switches

  • Limit switch connecting guide

  • Replacement of TF blades

  • Wire gluing in PR3

  • Type-B remedying work

• Criteria in the acceptance test.

  • Inspection document (sample)

Safety

Discussion

• Necessity of SR3 suspension removal.

Travel Plans

The week from 12/28

The week from 1/4

• Takahashi: 1/4-8
• Sato: 1/4-8
• Hirata: 1/4-8
• Yano: 1/4-8

Next meeting

• On 2020/1/8(Fri)