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Reports until 17:07, Monday 18 October 2021
gerardo.moreno@LIGO.ORG - posted 17:07, Monday 18 October 2021 (60310)
CP1 Overfill Via Script

I ran the script with the following settings: CP1_Fill.py 100 -130 600.  Overfill verified via one of the site cameras.

Note from script:

CP1 Fill completed in 37 seconds. Starting CP1 fill. LLCV enabled. LLCV set to manual control. LLCV set to 100% open. Fill completed in 37 seconds. TC A did not register fill. LLCV set back to 34.6% open.

From the note it appears as if TC A had some lag regarding the temperature readout, because on the attached plot it shows its temperature did go below -130 deg C.


Images attached to this report
kyle.ryan@LIGO.ORG - posted 16:36, Monday 18 October 2021 (60308)
Ready to vent Y-end in the morning

Gerardo M., Travis S., Kyle R.

An RGA scan was taken before and after hard-closing GV18.  The instrument air compressor, Class-100 vent/purge air supply, QDP80 and Turbo pumps were also started.  We are ready to vent the Y-end station following the 0900 site activities meeting in the morning.  Note that there will be dirty activity following the vent which will prohibit BSC door removal tomorrow. 

LHO General
nidhi.patel@LIGO.ORG - posted 16:13, Monday 18 October 2021 (60307)
OPS Day Shift Summary

TITLE: 10/18 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
SHIFT SUMMARY: Construction, HAM5/7, and PSL work continues. EY vented. LVEA is Laser HAZARD.

Date UTC (local)

18-10-21 15:34 (08:34 AM) Karen and Kim in LVEA                                 
18-10-21 15:35 (08:35 AM) NDS0 is restarted
18-10-21 16:14 (09:14 AM) Cheryl in PSL
18-10-21 16:53 (09:53 AM) Mitchell and TJ in HAM5/7/beer garden area
18-10-21 17:07 (10:07 AM) Jenne in PSL
18-10-21 17:07 (10:07 AM) Karen and Kim are out of LVEA
18-10-21 17:17 (10:17 AM) Varun in PSL
18-10-21 17:37 (10:37 AM) Mitchell and TJ are out of LVEA
18-10-21 17:55 (10:55 AM) Camilla and Sheila in HAM5/7 area
18-10-21 17:59 (10:59 AM) Betsy, Lee, Win in LVEA
18-10-21 18:10 (11:10 AM) Georgia in LVEA
18-10-21 18:12 (11:12 AM) Keita in HAM5/7 area
18-10-21 18:12 (11:12 AM) Betsy is out of LVEA
18-10-21 18:30 (11:30 AM) Georgia is out of LVEA
18-10-21 18:30 (11:30 AM) Keita is out of LVEA
18-10-21 18:37 (11:37 AM) Rahul in HAM5/7
18-10-21 18:38 (11:38 AM) Jim headed to EX to check on HEPI pump
18-10-21 18:49 (11:49 AM) Karen and Kim are out of EY
18-10-21 19:21 (12:21 PM) Varun, Cheryl, and Jenne are out of PSL
18-10-21 19:23 (12:23 PM) Rahul is out of LVEA
18-10-21 19:52 (12:52 PM) Lee and Wen are out of LVEA
18-10-21 19:59 (12:59 PM) Camilla and Sheila are out of LVEA
18-10-21 20:00 (13:00 PM) Jim headed to EX to grease the HEPI pump
18-10-21 20:12 (13:12 PM) Varun and Cheryl in PSL
18-10-21 20:33 (13:33 PM) Travis, Gerardo, and Kyle heading to EX to prepare    for venting EY; per Betsy's instructions: set guardians SUS_ETMY and SUS_TMSY   to SAFE (noticed that SUS_TMSX and SUS_ETMX guardians were set to Damped,       changed them to ALIGNED); per Jim's instructions: 1) turned off sensor          correction for ETMY by setting SI_ETMY_ST1_SC to CONFIG_SC_OFF. 2) set the gain of H1ISI-ETMY_ST2_ISO_RX and RY DoF to zero. 3) and then set watchdog SEI_ETMY  to ISI_DAMPED_HEPI_OFFLINE.
18-10-21 20:47 (13:47 PM) Jim is back from EX
18-10-21 21:11 (14:11 PM) Camilla in HAM7
18-10-21 21:15 (14:15 PM) Sheila, Lee, and Wen in HAM7
18-10-21 21:22 (14:22 PM) Jenne in PSL
18-10-21 21:52 (14:52 PM) Betsy in HAM5/7
18-10-21 22:12 (15:12 PM) Betsy is out of LVEA
18-10-21 22:48 (15:40 PM) Cheryl is out of PSL
18-10-21 22:48 (15:48 PM) Jim headed to EY to troubleshoot HEPI pump
18-10-21 23:09 (16:09 PM) Jim is back from EX

LHO General
bubba.gateley@LIGO.ORG - posted 13:27, Monday 18 October 2021 - last comment - 14:03, Monday 18 October 2021(60304)
Update to A+, most of the re-bar is installed and ready for last section of the FCTE slab tomorrow and prepping for forming and rebar for FCES slab. Also some plumbing going in for pressure testing before pour. 
Images attached to this report
Comments related to this report
jeffrey.kissel@LIGO.ORG - 14:03, Monday 18 October 2021 (60306)EPO, FMP
Tagging EPO and FMP.
daniel.sigg@LIGO.ORG - posted 11:26, Monday 18 October 2021 (60303)
105kHz interface chassis

Installed the new 105kHz interface chassis, D2000552, in the R1 squeezr rack position U6. It is powered up and all cables are connected. Also connected the DAQ cable at the rear of the LSC front-end chassis.

LHO General
nidhi.patel@LIGO.ORG - posted 10:56, Monday 18 October 2021 (60302)

Work Permit 9986

betsy.weaver@LIGO.ORG - posted 10:07, Monday 18 October 2021 (60301)
15' tube craned to West Bay

The first cleaned 15' FC Tube has been craned over to the West bay in/or near the small baffle cleanroom (it has passed FTIR sample testing).  Corey is go for the next round of baffle installation.


H1 General
camilla.compton@LIGO.ORG - posted 09:23, Monday 18 October 2021 (60300)
Check Dust Monitor Vacuum Pumps - FAMIS Task 17463

Previous alog#60039. Following Nidhi's instructions in T2100415. Closes FAMIS 17463.

    Pressure (in Hg) Temperature
Location Noise Before After Value (deg F) Location on the Pump
CS OK 17 19 155.8 - 159.9 Pump housing - (took multiple measurements, between 155.8-159.9deg range)
EX OK 18 19 Within range All
EY OK 17.5 19 Within range All
camilla.compton@LIGO.ORG - posted 09:15, Monday 18 October 2021 - last comment - 14:01, Monday 18 October 2021(60299)
HEPI Fluid Level Check - Monthly FAMIS Task

Closes FAMIS 17360

  Level (inches)      
Location Value Difference from
last reported levels
Recorded Trip Level  Drip Pans Leaks Comments
CS 5 13/16 0 5 11/16 Clean None new  
EX 7 11/16 0 7 10/16 Clean None new Metallic grating sound coming from motor?
EY 8 11/16 0 8 6/16 Clean None new  

Updated local T1500280 to a v23. Performed CS on 11-Oct-2021, EX,EY on 15-Oct-2021.

Comments related to this report
jim.warner@LIGO.ORG - 14:01, Monday 18 October 2021 (60305)

Camilla notes extra noise coming from the EX HEPI pump. I went down to look, and there is definitely an extra, barely audible whine coming from this pump which sounds like some extra bearing noise. I found Hugh's old grease gun and tried to force a little more grease in to see if that would improve things, but it just seemed to squirt out around the zerk. The sound did not improve after Nidhi ramped the pump back up for me. There is also some extra occasional grumbling coming from this pump station that doesn't sound normal either. It seems to run fine, the control drives all seem normal and haven't changed at all over the last ~100 days. I'll keep checking on this, but we may need to think about pulling and servicing this unit before too long. We have already replaced this unit before, noted in alog 51608. That replacement was proceded by an increase in the drive needed to maintain pressure, discussed in 51559. I'll start looking at our spare pumps and try to figure out what we need in order to be ready in case of a failure.

LHO General
nidhi.patel@LIGO.ORG - posted 08:17, Monday 18 October 2021 (60298)
Ops Day Shift Start

TITLE: 10/18 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
    Wind: 1mph
QUICK SUMMARY: Construction work continues. LVEA is laser SAFE, but will be transitioning to laser HAZARD after 9 am.

sudarshan.karki@LIGO.ORG - posted 20:14, Sunday 17 October 2021 - last comment - 20:18, Sunday 17 October 2021(60294)
Temperature coefficient of Pcal transfer standard (TSA)

SudarshanK, RickS

We created two new transfer standard, TSA and TSB in order to facilitate the transfer of laser power calibration between the  national metrology institutes (NMIs) and the various observatories. We are in the process of characterizing these new transfer standard. We have made couple of measurements in the  last few weeks. The result from those measurements will be posted at same later date. Here we present the measurement of temperature coefficient of TSA that was made yesterday.

TSA was in the oven since 3:00 PM  Oct. 12, set at the temperature of 39 deg C. On October 13, the responsivity ratio between TSA and TSB were measured letting the TSA to cool from its heated temperature of 39 deg. C.

The measured temperature coefficient of the newly assembled transfer standard TSA is about 1.5 hops/deg C. When analyzing the data, the points where the temperature gradient is too high, in the beginning, and  where the standard has reached the equilibrium, towards the end, has been ignored. The first fit in the plot is made using all the data under consideration. The second fit is made by decimating the data in order produce equally spaced data and thus remove the bias that arises for having more data at lower temperature difference. The difference in temperature coefficient is minimal from these two different methods.

All the data and the jupyter notebook used to analyze the data can be found here:


Non-image files attached to this report
Comments related to this report
sudarshan.karki@LIGO.ORG - 20:18, Sunday 17 October 2021 (60295)CAL

An attempt to make a second temperature coefficient measurment on 10/14 failed because the laser tripped early on during the measurement. The partial data that was collected can be found here:



gerardo.moreno@LIGO.ORG - posted 00:30, Saturday 16 October 2021 (60293)
New Turbo Pump Station Inside Y-End Station VEA

(Kyle R., Travis S., Gerardo M.)

As previously noted in Kyle's entry, to position the new turbo pump station inside the VEA was a bit more involved than just pushing it into place.  After some measurements of the VEA components, the use of the crane to move the new turbo pump station was rejected, the measurements revealed that there was no room to move the station over the huddle of cleanrooms in a safe manner.  Plan B, we opted to move the staircase with the crane a bit, enough to allow the station to squeeze by and get it to near its final location.  The staircase was moved back to its initial position.  Also, GV18 was not operated.

gerardo.moreno@LIGO.ORG - posted 23:44, Friday 15 October 2021 (60291)
CP1 Overfill Via Script 3 Times

(Travis S., Gerardo M.)

We ran the autofill script 3 different times, 2 times with a successful result per the script, and one time the script stopped due to temperature error as reported by the thermocouple, settings are as shown when the script is ran.

First time running the script, overfill noted via one of the site cameras.  Script results below:

~./CP1_Fill.py 100 -130 600
CP1 Fill completed in 27 seconds. Starting CP1 fill. LLCV enabled. LLCV set to manual control. LLCV set to 100% open. Fill completed in 27 seconds. TC B did not register fill. LLCV set back to 34.5% open.

Second time running the script, some LN2 noted via the site camera, but it does appear as if it was successful due to the temperature reported by both TCs.  Script results below:
~./CP1_Fill.py 100 -150 600
CP1 Fill stopped, TE error. Starting CP1 fill. LLCV enabled. LLCV set to manual control. LLCV set to 100% open. TC A error. TC B error. Fill stopped. LLCV set back to 34.5% open.

Third time running the script, Travis ran the script and I was present by the discharge line, visually noted LN2 flow.  Script results below:
~./CP1_Fill.py 100 -130 600
CP1 Fill completed in 21 seconds. Starting CP1 fill. LLCV enabled. LLCV set to manual control. LLCV set to 100% open. Fill completed in 21 seconds. TC B did not register fill. LLCV set back to 34.5% open.


Images attached to this report
cheryl.vorvick@LIGO.ORG - posted 20:46, Friday 15 October 2021 (60292)
PSL measurements and prep for Faraday alignment

Today on the PSL we took beam measurements, and started the modifications for revisiting the Faraday alignment.



- Cheryl, Varun

Images attached to this report
kyle.ryan@LIGO.ORG - posted 16:36, Friday 15 October 2021 (60290)
More turbo install prep at EY

I had to waste invest more time than expected to reverse engineer some differences between the "as built" wiring terminations vs. the drawings but was able to figure it out eventually.  Next week, we'll use the existing iLIGO pump system as standby during the vent.  Once the vent is completed, we will then remove the iLIGO Turbo Station and the iLIGO 10" isolation gate valve and install a new VAT gate valve and the -v1 Pfeiffer Turbo Station.  We will then pump back down using the hybrid setup consisting of the new Pfeiffer Turbo backed by the iLIGO Edwards QDP80 backing pump by using a custom control cable.  Once the recovery pump down is done and the pumps shut down, the iLIGO QDP80 will get replaced with a new HEPTA pump and then both newly installed pumps can be brought up to the current revision.  In a perfect world, this could happen ;)

thomas.shaffer@LIGO.ORG - posted 15:39, Friday 15 October 2021 - last comment - 08:17, Monday 18 October 2021(60287)
OFI Shroud roof complete

Mitchell and I finshed all of the OFI shroud brackets and got the last roof panel on that we didn't finish yesterday with Betsy. Next up will be to add the input and output shroud panels, and then what we have of the side panels. Following that we will align the panels and tighten down all of the hardware.


Comments related to this report
thomas.shaffer@LIGO.ORG - 08:17, Monday 18 October 2021 (60296)

Attached pictures of the almost completed roof, and some of the imperfections we found on some of the panels.

Images attached to this comment
jeffrey.kissel@LIGO.ORG - posted 20:46, Thursday 30 September 2021 - last comment - 16:59, Monday 18 October 2021(60082)
HPDS Controls Infrastructure (for ZM2, ZM4, and ZM5) Functional and Ready
J. Kissel

Just in time (see LHO aLOG 60078), I've finished designing the MEDM screens for the HAM Piezo Double Suspensions (HPDSs), and filled out all the macro files, set up the EPICs parameters and filled out the foton files, and saved settings to the safe.snap of the SDF systems involved for ZM2, ZM4, and ZM5.

These new screens are now call-able from the sitemap as any normal suspension; ZM2 is under the SQZ IN menu, and ZM4 and ZM5 are in the SQZ OUT menu.

This is a resumption, continuation of, and completion of the work started in LHO aLOG 59696, and the comments there-in. The upper half of the HPDS OVERVIEW screen, controlling the M1 top mass stage is virtually identical to the ZM6 HSDS infrastructure. The lower stage brings to life the rudimentary fast front-end Simulink and Beckhoff control system that Daniel put together (see LHO aLOGs 59992 and 59993, respectively) that should get us through testing and commissioning this stage. Of course, I'd like to see this rudimentary infrastructure filled out more, so I include some wishful thinking on the screens, in hopes to guide future development.

I also note that this is the first SUS that's being driven and sensed by complete mish-mash of fast ADCs and DACs in the MER, a fast DAC in the CER, and some beckhoff ADCs for the PZT monitors and strain gauge readout. Quite a challenge for the MEDM macro system!

New screens have been committed to

the screenshots for which are shown in that order, using the ZM2 instantiation.
The macro files that support them have been updated,
such that, LLO only has to svn up these directories (and link them in the right way to their sitemap) to receive the goodness.

Everything should be ready to go for testing when Nidhi, Fred, and Rahul get to it!
Images attached to this report
Comments related to this report
jeffrey.kissel@LIGO.ORG - 17:13, Friday 01 October 2021 (60102)SQZ, TCS
J. Kissel, L. McCuller

I've now walked Lee through these screens, and he has the following redlines:
   - The "DIOPTERS" imagined output is actually *change* in defocus in diopters. Thus, it doesn't make sense to convert this to ROC.
   - Instead, there's a nominal radius of curvature that creates a nominal defocus lens, and the PZT pushes strain on the optic to create a change in the nominal defocus of the optic, creating a delta defocus. As such, it really only makes sense if  the "ROC" readout is 
    ROC = 2 / (nominal ROC's defocus + delta defocus), 
where "nominal ROC's defocus" is an EPICs record (informed by the design T2000101, or a measured value), and "delta defocus," dD, is the live channel converted from the strain gauge voltage.
   - Also, we would love it if the live channel, dD was zero at the nominal radius of curvature (or defocus). As such, depending on the real system and the payload, and other offsets in the wheatstone bridge readout of the strain gauge may happen. So, we need an EPICs write, additive offset at each step along the way of the strain gauge readout calibration into dD (delta defocus): at the ADC voltage step, the strain step, and the defocus step. Not to say that we would use all of those offsets, but having them there at each step means that however one measures or frames the offset, one can stick it in at the right conceptual place.
   - Finally, once we get all of these "make the signals meaningful" tweaks, let's add a slider on the offset for dD / diopters to make the actuation meaningful as well. This requires quite a good bit of understanding of all the complexities of PZT drives, strain gauges, bending of constrained optics under central force, but I think we'll get there, especially with superb characterization like that in LLO aLOG 57322.

In addition we brainstormed about the ideas for what he might imagine being in the " [ ... ] " section of the screen -- i.e. what might be the connective control system between the strain / defocus readback and the PZT drive voltage.
   (1) We say out loud, that it's WAY too early to consider such a control scheme, but you might imagine -- say for the SQZ to IFO ZM4 / ZM5 path -- that there is an interferometric (bullseye) sensor measuring the mode matching between the SQZ path and the IFO OUT path, then you would have an "ISC INF" path that requested an adjusted change in diopters, dD, which then, via the readout of the strain gauge, drove the correct amount of PZT voltage to get there. And thus, you could get a loop that optimized the mode matching between the IFO and SQZ paths. Again -- WAYYYY to early to think about such things, but the idea is there. I won't build this into the MEDM screen.
   (2) One might also imagine that if you want to keep a fixed value, offset from nominal, for the change in defocus, dD (i.e. the strain gauge readout), then you could wrap a loop around dD, driving the PZT voltage just to keep the strain/defocus constantly at that value. Now, what would be the noise sources of that loop that would make that be noisy or drift? Who knows, and probably the answer is "there aren't any," other than slow decay in the gain of the PZT driver or something. But, it's another loop one might imagine. 

For now, though, we agree that we *don't* imagine we need to make further changes to reflect any of these (made up?) dreams. Other than the offset, the correction to the imagined math to get the "ROC" value to be meaningful, and the slider control of dD, we shouldn't need *anything* more sophisticated than a "good ole EPICs servo" where we slowly make "this EPICs record" to "this number" using "this EPICs channel to drive it there" at a "way slower than EPICs" UGF.
jeffrey.kissel@LIGO.ORG - 16:59, Monday 18 October 2021 (60309)ISC, SQZ, SUS
I've implemented the MEDM screen modifications to include the redlines from the comment above, LHO aLOG 60102. See attached screenshots of updates. Note, since I only changed the strain gauge side of the M2 stage, the second attachment is a zoom in on that bottom left corner where all the action is.

Of course, none of this code exists in beckhoff yet, but hopefully, since the PLC is "just code," visualizing the design intent like this will help make the coding easier and make the code more legible.
Images attached to this comment
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