Agenda/Minutes on 2020/10/16

CRY+VIS Interface Meeting

13:30-

Participants:

14:00-

Participants:

[Fabian]

I wrote a document about the procedure to replace the LVDT cards after a failure: JGW-T2012128.
- It was checked by Alessandro Betolini from Nikhef and he says the method is correct. He provided minor comments that have been incorported to the new version of the document.
- He says they will review the design for ETpathfinder and that's our chance to give them feedback (i.e. Tanaka-san's findings and my concerns as a user).
- Knowledge transfer from Tanaka-san to Alessandro would be greatly beneficial for KAGRA. If you think it's suitable, would it be possible for someone to organize this, please?
Tanaka-san will take some of our LVDT cards for hardware modification.
- We need to survey those LVDT cards before he takes them away. When will we do this?
- As far as I understand, given the old calibration factor, he has to give us a procedure to calculate a new calibration factor. Is this statement correct?
- Before any other card breaks, we need to survey all of them. When will we do this?
- Four hands are required for the measurements. For Type-B/Bp, Washimi-san and Fabian can do it.
After cleaning the PR area I have the impression we lost Hirose-san's LED lamps to check mirror cleanliness.

[Washimi]

I gave some feedback for the noise budget paper.
We finished the cleaning with a lot of help.
Hirata-san made M6 holes in some ballast masses.
We removed some cables from chassis for the cleaning procedure.
I put the fibre optic camera in the PR clean booth buffer area.
We recovered the suspensions after blackout. They all went to ALIGNED state well.
The temperature has decreased a lot inside the clean rooms, likely due to an increase of cold air circulation after turning all FFUs on. A couple of DC control loops in GAS filters are about to saturate. I've reported this to Miyoki-san and he turned on some heaters.

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After the blackout PR2 went to ALIGNED state well. PR3 and PRM oplevs were removed before recovery and I just checked they went to TWR_DAMPED state. I can turn the IM control system on by hand to check the health of IM-OSEMS.
Just for the record for new comers: I realized PR use different amplitudes of reference signals for the LVDTs. According to labels attached to signals generators:
- PR2: 6 Vpp.
- PR3 and PRM: 7 Vpp.

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RSE Trial was finished on Oct. 13th.
Preparation work is on going.
- Inventory sheet.
- Stock record.
- Cleaning by the company
- Monitoring for vent. Date: 19(only EYV), 22-25(practically 22-23). Charge: Miyo, Ikeda, Fabian, Takahashi
Schedule.
- Chamber opening
- VIS
Procedure documents.
Criteria in the acceptance test.

The week from 10/19

The week from 10/26