= Agenda/Minutes on 2020/11/6 = [[https://zoom.us/j/203743987|Zoom Meeting]] = CRY+VIS Interface Meeting = 13:30-14:00 Participants: Takahashi, Hagiwara, Miyo, Hirata, Ikeda, Yano, Sato, Aso, Ushiba, Matteo, Sugiyama, Kimura * [[http://gwwiki.icrr.u-tokyo.ac.jp/JGWwiki/KAGRA/Upgrades/PostO3Upgrades|Post O3 Upgrade portal]] * Cryo-payload was disconnected on 11/3 and the wire was taken down under the cross tube on 11/5 in Y-end. * The L-parts and tie-rods in IYV were replaced. The effects will be checked on 11/20. * Schedule: Wire disconnection (IX 11/13, EX 11/19), WAB safe mode (10/26-11/13). * Jig for the FC painting. * PF actuator: Measurement of coefficients and calculation of the noise (by mid Dec.). = VIS Meeting = 14:00-15:00 Participants: Takahashi, Sato, Miyo, Hirata, Ikeda, Yano, Suguyama, Aso, Tanaka, Washimi, Terrence, Fabian == Progress report == === General === [Miyo] I asked Nakagaki-san who is a new engineer in ICRR to investigate the cabling for all VIS rack. [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=11573|diagram]] * He found wrong cabling in the LVDT driver for BF damper in PRM. Detail is written in Type-Bp section. ==== About LVDT cards ==== [Fabian and Washim-san] With the new information that Alessadro (Nikhef) provided a few weeks ago, we began measuring the settings in PR suspensions. * I realized that the some of the information given to us ([[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=4798|JGW-T1604798]], Feb 2016) about how to set up the card ready for calibration was '''wrong'''. * '''Namely, in order to set the phase, it is instructed to use the wrong probe points.''' * I wrote Alessandro for confirmation and he provided the correct information. * The consequences for the already calibrated LVDTs are not necessarly so important: * As far as I remember, the people adjusted the phase by maximizing the output, not by measuring the phase directly. * Still, from the recent measurements, I can see that some phases are very different from zero, which means we are not having the best SNR we can get from the LVDTs. * The consequences for LVDT card recovery are more important because, in case a card needs to be replaced, we have to get the same settings in order to preserve the calibration factor. * In case a card, whose settings have not been measured, breaks, we should: * Measure the value of two gain resistors from the top of the card and * Measure the value of one resistor from the '''bottom''' of the card. This requires removing the card from the chassis. === Type-A === * Cryo-payload was disconnected on 11/3 and the wire was taken down under the cross tube on 11/5 in Y-end. * Started the disassembly of Type-A tower in Y-end. The F1 was dismounted. ([[http://klog.icrr.u-tokyo.ac.jp/osl/?r=15372|Mon.]], [[http://klog.icrr.u-tokyo.ac.jp/osl/?r=15382|Tue]], [[http://klog.icrr.u-tokyo.ac.jp/osl/?r=15391|Wed.]], [[http://klog.icrr.u-tokyo.ac.jp/osl/?r=15400|Thu.]], [[http://klog.icrr.u-tokyo.ac.jp/osl/?r=15411|Fri.]]) === Type-B === [Fabian and Washimi-san] * I got the reviewer's comment on the Type-B paper. It's a long list but many of them are relatively simple. A few of them are a little more challenging. * We began setting up the clean booth ready for work. We also had had a chat about safety and how to keep the cleanliness. * We removed most of the screws from the top of BS and SRM chamber and from the +X side door of SRM chamber. * Akutsu-san and Nakamura-san inspected the BS oplev area with the intention of designing the box. * Mirapro covered the BS/PR2 area with SUS sheets. === Type-Bp === * We measured the settings of PR2, PR3 and PRM GAS Filters LVDT cards: two resistances and a phase for each channel. * We'll check the remaining LVDT card in PRM once the cable problem is solved. * About: the LVDT driver box for PR2 GAS filters: * It has a problem with the input power voltage, but it may be just an LED issue because the meaured voltage seems alright. Shimode-san will check on Tuesday. * However, I didn't get a return signal from the BF-V LVDTs back into the board. The board might have broken. After Shimode-san finishes checking the power issue I'll investigate more. [Miyo] Only the PRM was cabled differently than the other Type-Bp suspensions for the LVDT drivers for BF-damper. [[http://klog.icrr.u-tokyo.ac.jp/osl/?r=15404|klog#15404]] * The D-sub cable for the secondary coil and the cable for the primary coil were swapped. * This wrong cabling may be happen in October 2018 when we replace the driver due to malfunction according to [[http://klog.icrr.u-tokyo.ac.jp/osl/?r=6499|klog#6499]] * As far as I know, glitch was occurred after this replacement and this problem have not been solved yet from last year. ([[http://klog.icrr.u-tokyo.ac.jp/osl/?r=9577|klog#9577]]) === Type-C === === Controls === === Electronics === * Circuit boards and electronics parts have been ordered. Some parts provider should be changed. == Towards O4 == * DGS update are on going. * Schedule. * Arrangement of personnel in Nov. ([[https://www.dropbox.com/s/ow2fvqozua9vghi/VIS%20schedule%20Nov.xlsx?dl=0|table]]) * [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=11475|VIS]] * Procedure documents. * [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=5500|Type-A tower installation]] * [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=11598|Limit switches]] <-- Revised. Small changes in assembly (add one more nut) * [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=11520|Limit switch connecting guide]] * [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=11978|Replacement of TF blades]] * [[https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=11878|Wire gluing in PR3]] * [[https://onedrive.live.com/?authkey=!AOLVVVKJ_Zpn-2c&cid=1447B05D5B571A84&id=1447B05D5B571A84!26691&parId=1447B05D5B571A84!26683&o=OneUp|Type-B remedying work]] * Criteria in the acceptance test. == Safety == * SUS plates were renewal in the BS area. == Discussion == == Travel Plans == The week from 11/9 * Takahashi: 11/9-13 * Sato: 11/9-12 * Hirata: 11/9-13 The week from 11/16 * Takahashi: 11/16-20 * Sato: 11/16-20 * Hirata: 11/16-20 == Next meeting == * On 2020/11/13(Fri)