<> = Agenda/Minutes = [[https://zoom.us/j/203743987|Zoom Meeting]] ---------- = CRY+VIS Interface Meeting = Date: 2021/10/29 13:00-13:50 Participants: Takahashi, Ikeda, Fabian, Yasui, Hirata, Aso, Yokozawa, Ushiba, Akutsu, Sato [[http://gwwiki.icrr.u-tokyo.ac.jp/JGWwiki/KAGRA/Upgrades/PostO3Upgrades|Post O3 Upgrade portal]] == Schedule == * IX: Health check. Repair of the BF actuator. Replacement of HPCD. TF measurement of the payload. * EX: Health check. Investigation of the BF damper (V). Replacement of HPCD. TF measurement of the payload. * Schedule: Replacement of the LVDT card and investigation on the WAB on 11/2. * IY: LVDT driver for IP/F0. H4 geophone. * EY: == Status == * Replacement of Flip cable: It will start from 11/5. * Mirror cleanliness: Report by Yasui * TM height setting: ITMY * Oplev: Setup of the TM Oplev in IY after the height adjustment. * ACC: Ready to install to EX. Measurement for IY is planed on 11/1. * Commissioning in air: Health check. Check of the IM PD in IX. * Commissioning in vacuum: * Overall commissioning: * Acceptance check: * PF actuator: At the in-vacuum commissioning. * New vacuum pumps for V-chambers: Nov. 25-26 in IXV. * Heater control: PR2 and SR2 are ready. PR3, IY, EY remain. == Discussion == ---------- = VIS Meeting = Date: 2021/10/29 14:00-14:50 Participants: Takahashi, Sato, Ushiba, Fabian, Terrence, Sugiyama, Aso, Hirata, Ishizaki, Tanaka == Summary Report == === Type-A === * Repaired the BF actuator in IX. * Replaced the LVDT driver for IP/F0 in IY. Calibrated the LVDTs. * Installed the H4 geophone in IY. * Investigated the vertical BF damper. The LVDT driver card should be replaced. === Type-B === * We raised SRM by 2.8 mm in accordance to the expected beam height: it is at the correct position now. * We measured the height of the BS to be 2.85 mm below the average height of the four flanges (Tomaru-san's marking). * We moved the GAS filter keystones with coil-magnet actuation: F0 and BF were close to zero and F1 was alledgely close to zero. * '''F1 LVDT is not working well''' (entry [[https://klog.icrr.u-tokyo.ac.jp/osl/?r=18191|18191]])''', so we checked the amount of actuation we used the last time we measured the height, when the LVDT was working, and used the same value''' (entry [[https://klog.icrr.u-tokyo.ac.jp/osl/?r=17338|17338]] from the 30th of June, 2021). This is fine because we had the same temperature (23.6 °C) and the fishing rod had not been used. * Then we raised the BS and measured it to be 0.3 mm below the reference. * In SRM LVDT pin assignment error: * We triple-checked the IP LVDT coil resistance values in order to discard any obvious errors. * Then we opened SR3 and SRM chambers and compared the wiring: they are indeed different; SR3 is the correct one. * Nevertheless, the IP LVDTs are still working! * The calibration curves look normal. See klog [[https://klog.icrr.u-tokyo.ac.jp/osl/?r=7087|7087]]. * We connected '''SRM IP LVDT #3''' to '''SR3 IP LVDT #3 driver''', and viceversa, '''SR3 IP LVDT #3''' to '''SRM IP LVDT #3 driver'''. Then we excited the suspensions slightly and inspected the behaviour of the six LVDTs in an Ndscope screen. Everything seemed very ordinary. '''We could not find any strange behaviour.''' * I'm not an LVDT expert, but I guess the LVDTs still work becuase of its symmertry. * __Question: I tend to think we should change the pin assignment, but the fact that they LVDTs are still working makes me doubt about changing them, what do you think?__ === Type-Bp === === Type-C === === Electronics === === Control === * Unification of the magnet assignment in the suspensions. == Schedule == See [[http://gwwiki.icrr.u-tokyo.ac.jp/JGWwiki/KAGRA/Subgroups/VIS/Schedule|Schedule]] * Type-A team: BF damper in EX (11/2). ACC for IY (11/1). * Type-B team: SF in BF, Flip cables (11/5), Wind shield == Safety == == Discussion == == Travel Plans == (Date in Kamioka) The week from 11/1 * Takahashi: 11/1-2 * Hirata: 11/2-5 The week from 11/8 * Takahashi: 11/9-12 * Sato: 11/9-12 * Hirata: 11/8-10 == Next meeting == * 2021/11/5(FRI)