This is Justin.
Per discussion in the morning meeting I have attenuated the power going into the IMC via the rotation stage. HWP set at 63degrees..corresponding to around 200mW. locked out power circuit when work completed.
model restarts logged for Thu 17/Jul/2014
2014_07_17 15:22 h1susetmy
rcg2.9 work on etmy.
J. Kissel, K. Izumi After using the (new) in-vac ISS QPD on the "second-loop" ISS array a bit this past week, we've made two changes to the H1:PSL-ISS_SECONDLOOP_QPD_SUM filter bank, which comes with the generic CDS Simulink library part /opt/rtcds/userapps/release/isc/common/models/QPD.mdl used in the h1psliss front-end model to represent it: (1) Installed a low-pass filter ( zpk([],[0.01;0.1],1,"n") ) (2) Changed the gain to -1, to invert the SUM which comes in negative. (1) makes determining whether the beam is on the QPD much easier in low-to-no light scenarios, and (2) is removing the analog inversion that seems common to aLIGO QPDs. A negative sum is less than the lower limit (1e-6) of the saturation block that's a part of the normalization scheme -- which means the PIT and YAW signals were always getting divided by 1e-6 creating ridiculously large numbers cut-off by the MEDM display. I've modified and committed the /opt/rtcds/userapps/release/psl/h1/burtfiles/iss/safe.snap such that these settings stick after a reboot. Things that still need to be fixed: The link to the FULL version of the SUM filter is broken. I think it's related to the generic macro variables passed down from screen to screen, but as far as I can tell the screen it's calling exists...
I installed the RTD temperature sensors on HAM 4 and 5. The existing HAM 4 RTD that was broken, Alog 11942, was replaced with a new RTD (D1102257-01 V1 SN# S1201366). HAM 5 had a functional RTD hooked up to the cable mount thanks to SUS, so the install went quickly enough. All of the sensor ends seemed to survive, but confirmation will have to wait until at least tomorrow when an impedance test can be done. The particle counts were good going into chamber. HAM 4 clean room: 0 HAM 4 chamber: 0 HAM 5 clean room: 0 HAM 5 chamber: 0
For the alignment work, all particle counts read zero in chamber in HAMs2, 3, and 5 (I was suprised at this being the case for 5)
Prior to balancing work beginning on HAM5, I locked the SRM and SR3 intermediate and bottom stage masses. I also tried to dress the cables as best that I could. Unfortunately the bolt holding the peek cable clamp feels galled so cant do up clamp well, so the cables are kind of just hooked onto the clamp. its not at all pretty, but hopefully will be fine. If had more time would of liked it to be better.
The SEI guys balanced HAM 5 and I then went and unlocked SRM and SR3. Hugh then unlocked the ISI and pulled the covers off the ISI for testing to begin
For HAM4 balancing we decided to leave SR2 unlocked because we didnt think the ISI would have to have much adjustment, if any at all. So it was left unlocked during balancing, the ISI balance checked and the covers are now pulled back from the ISI for testing to begin
Thus SR2, SRM, and SR3 should all be unlocked....and hopefully free. I have not unlocked them into their "final state" as they need to be locked up again so that they can be first contacted
HAM4/5 suspensions were checked for rubbing with a dtt tf in pitch (top mass) and compared with previous measurements. Results are in the pdf attached, they all seem to be freely suspended. dtt files were checked in the svn under : SusSVN/sus/trunk/HSTS/H1/SR2/SAGM1/Data/2014-07-16_1800_H1SUSSR2_M1_WhiteNoise_P_0p1to50Hz.xml SusSVN/sus/trunk/HSTS/H1/SRM/SAGM1/Data/2014_07_16_H1SUSSRM_M1_WhiteNoise_P_0p01to50Hz.xml SusSVN/sus/trunk/HLTS/H1/SR3/SAGM1/Data/2014_07_16_1800_H1SUSSR3_WhiteNoise_P_0p1to50Hz.xml
WHAM4
The HAM4 level balance was fine. There is one horizontal locker that shifts 1750counts (our spec is 1600) but all others are less than a few 100. Adjusting the locker to correct this will only change the locked position; the floating position will not change. See the first attached plot for the shift from locked (whence alignment has been done) at the start of these trends, to the unlocked position at the end of the traces. The Rz is the likely most significant at 15urads, Rx is 10urads with Ry at 3urads.
WHAM5
HAM5 required some mass shifting to balance the level. HAM5 H1 is a bit worse than HAM4 with a shift of 2500counts. See the second attached for the cartesian shifts. Note Rz is 30urads.
M. Heintze, K. Izumi, J. Kissel Ah what wonders a break can bring. Kiwamu did some trending during the break to discover I was reading the OSEM Witness Sensors incorrectly. We had way over-shot where we needed to be in pitch, which we believe to be the source of the yaw misalignment. After a few more turns of the pitch adjuster back towards where we needed to be, we regained a spot on the REFL WFSs, and were able to restore the IM4 mechanical alignment to the former, close-to-saturation digital alignment. See attached screenshots of REFL WFS screens, for a before and after. IM4 baffle has been restored, and tools removed from the table. As an act of caution, we'll keep the bypass path in until tomorrow lest we need it again for some terrible, terrible reason. Final alignment values for all suspensions are also attached. P.S. Next time we bypass the IMC, let's use optic mounts which are less sensitive to fairy kisses.
Yes we should use mounts whose actuators can be locked if this needs to be done in the future
During the process of changing the IMC incident power in the past few days, I noticed that the rotational stage had not been calibrated. So I calibrated it by using old data (see alog 9306).
It now gives a coarse estimation of the angle-power relation. The calibration is, sadly to say, not so accurate any more at the point -- I saw an expected power of 600 mW even though the actual power is now at 1 W. Anyway, it should at least give us which direction to go when we need to rotate it.
=== some details ===
I used a least square fitting from gnuplot.
It looks like the data from the ETMY STS is not getting saved to the frames correctly. If you look at the attached plot, it shows an ASD of the ETMY STS. I've plotted both the data (5 minutes of data starting at 17 July 00:00 UTC) from the SENSCOR channels (H1:ISI-ETMY_ST1_SENSCOR_GND_STS_X/Y/Z_FIR_IN1_DQ) and ISI-GND channels (H1:ISI-GND_STS_ETMY_X/Y/Z_DQ) - no filters have been applied, this is just the raw data. The SENSCOR channel looks fine so we do not think the sensor is broken, but the data isn't being saved correctly to the H1:ISI-GND_STS_ETMY_X/Y/Z_DQ channels. Summary - Data is not being saved correctly to the H1:ISI-GND_STS_ETMY_X/Y/Z_DQ channels.
Vern, Jim, Jeff, Dave. We can confirm the data is being corrupted somewhere within the model. Jeff is emailing the details to the ISI group.
J. Kissel, D. Barker Dave traced the problem down to a corruption of this particular STS channel at the GND_STS library part level, which stores the calibrated STS2s (or T240s) in the frames (installed last September by Hugo). The data looks live and well at the point at which these calibrated signals exit the STSINF bank, and enter the ST1_SENSCOR bank, but not in the test points in the GND_STS block where they're stored into frames. See attached ASD.pdf. The GND_STS versions of these channels take a pretty adventurous path through the simulink/front-end model from where they're generated (deep inside the ST1 block) up to where they're stored (at the top-level), so we suspect there's a problem with the level traversal. There is a point where buses and tags are used to traverse levels, so we immediately suspect this because of past history with battling the RCG, but what's strange is that -- other than the top level -- all parts are common to all BSC-ISIs, so this problem should be systematic if this is *actually* the problem -- but its not. Let us know if you have any advice from off-site. Also -- and "svn st -u" reveals that LHO's local copy of the isi corner of the userapps repo, /opt/rtcds/userapps/release/isi/ needs some serious clean-up.
J. Kissel Sheesh .... more confusion. I just took a look at the ETMX channels to see if all of those were the same. They're pretty close, but only two are identical -- those channels *before* the input matrix. I expect them all to be identical. What gives? The SENSCOR version of the channel is the only one *after* the input matrix, and it looks like the input matrix is mapping X to Y and Y to -X. Is this making up for a bad analog cable connection? Is this based on some commissioning effort? I know it's a T240 an'all (see LHO aLOG 10635), but the wiring diagram (see D1400077) indicates no such tomfoolery...
800 - Kate Gushwa working on baffles @HAM4 845 - Manny to end stations to work on property management checklist 911 - Jeff B to LVEA test stands to work on BS Baffle 958 - NathanZ working with NPRO in OSB optics lab 1008 - Betsy on walkabout in LVEA 1009 - Gerardo tracking down viewports in LVEA 1020 - Jeff shaking HAM2, engaging and resetting countdown timer on IOP SWWD 1024 - Sheila says she is finished with green light at EX, transitioned to laser SAFE 1100 - Praxair delivery 1310 - SR crew breaking for lunch, will continue at HAM 2 in one hour 1310 - SR handing off output arm to GregG for RTD install 1316 - Arnaud on moth overwatch duty at HAM 2 1327 - Karen cleaning at EY 1328 - Hugh and Jim moving to HAM 4 to hurry along the RTD cable install and prep for balancing 1419 - Jeff/Andres/Dan moving to output arm work 1500 - Ops meeting
Enough of the alignment of the corner station optics had been completed enough to free up the BS and ITMy for chamber closeout preps. So, I locked the ITMy test mass and CP mass in prep for First Contact cleaning. Although the ISI is not yet locked, we all decided it was OK for me to lock the BS optic and it's PUM, so I did that too while I was in the BSCs.
ITMX, right?
Yes, yes, ITMx!
Betsy, Filiberto, Rai, Calum, Rich We successfully repaired two elements (1&5) that were shorted by one of the wires that suspends the compensation plate (CP) on ITMY. Rai machined two tools (2mm wide razor chisel and a carbide cutting tool fashioned into another tiny chisel) for us to use to remove a small portion of the gold mask on the CP. The tools worked very well and we were able to cut two ~2mm gaps in the gold traces thus eliminating the short circuit path. Everything went well. After cutting the gaps, we checked that each wire had proper continuity from the airside of the vacuum feedthrough all the way to each pattern on the CP ESD mask. From the airside of the vacuum feedthrough, each of the 5 center conductors were HIPOT tested at 1kV to chamber ground for 1 second with the tester set to alarm at 300uA. The same HIPOT test was performed between each isolated shield and chamber ground. All connections are normal. There was a report of at least one problem with the 5-way coaxial connector on the vacuum side of the vacuum feedthrough that will require rework at a later date. Once the majority of the doors are back on the chambers, there will be decent positive pressure such that the feedthrough can be taken off and the cable pulled through into the air and reworked in situ. We have done this successfully on other similar connections. Filiberto and I went through the necessary steps to repair that connector when the time is right. Betsy is taking a couple of photos of the repair to be posted soon.
(Corey, Filiberto)
Keita walked us through a ground loop he noticed on the TMS (the cable which goes to 4 [of 6] BOSEMs on the TMS). I went in chamber and Filiberto went to the air-side of the flange for this cable.
The air side cable we disconnected this morning is H1:SUS_TMONX-1. We also disconnected H1:SUS_TMONX-4 and found no short. Both cables are on Feedthru E6 subflange 7.
This is the same as one of the failure modes found in HAM6.
https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=12348
Scroll down to "annoying cable and connector problem" in the above alog. Also look at the picture in that same alog.
1. Ground loop check
Sheila and Arnaud checked the ground loop from outside and one of the TMSX BOSEM cables was bad. Nothing was done to fix it yet.
2. Putting Pico collars and kapton washers
Though I asserted to Corey that EX picos have collars, I was wrong. We put the collars on picomotors where possible, but there was two picomotors (M14 PIT and M3 YAW) where there was not enough space. See pictures.
Then we put kapton washers to all picomotors.
3. Relieving HEPI bias by rebalancing TMS
Some change in the behavior of SUS guardian seems to mean that the SUS bias is not restored by requesting "align". Because I and Sheila were both unaware of this, we tried to "confirm" our alignment with the HEPI bias on with slightly wrong ETMX bias (turned out later that it was about 30urad too much), and we couldn't quite align the TMS, but estimated from the distance of the forward-going and back-going beam on one of the HWP that we needed 30 urad more headroom to align it. (So things were consistent in the end.)
Anyway, we ended up having to relieve about 300 urad of TMS bias in PIT by moving PIT balance masses on the TMS.
4. Setting up ISCTEX for realigning IR QPDs
First we tried to use Sheila's setup as is, but it turned out that the beam would get too large inside the TransMon telescope.
We removed the lens in the IR TRANS monitor path on ISCTEX and that made things better. After much iterations, we reasonably aligned the IR beam such that the beam retro-reflects from the ETMX and the beam position on the secondary is on top of the green beam within 2mm or so. The IR beam diameter coming out of the arm is about 6mm on the secondary, so 2mm is not very small but should be good enough to put the beam on QPDs.
5. Aligning the steering mirrors on TMS
Not surprisingly, the IR beam was very close to one of the green beams on the QPDs.
We found that the beam was totally off on the QPD sled and was not making it to the QPDs, but just moving M14 was good enough to bring the IR beam on both QPDA and QPDB. It's somewhat puzzling that people could not center the QPDs using M14 and M4, but again it's kind of hard to turn the right knob for the right degree of freedom because two mirrors are almost degenerate (https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=11897).
Two disappointments were that the beam was bigger than the 3mm QPD (it looks like 4mm or maybe more), and that the IR power seemed to be too small to be useful for centering. The latter was surprising as the OzOptic laser is nominally 10mW, and given the 95% splitter in the path the power on each QPD should be about 10E-3*0.95*0.05*0.5 = 240uW, which doesn't sound terrible.
Anyway, our mission is to bring the IR beam centered on both QPDs within 1mm, and keep the IR path to the ISCTEX at about the center of the clear aperture formed by the chamber/viewport/table enclosure, to make sure that the pico mirrors can take care of the fine centering job without destroying the in-air IR path. We will center both of the QPDs using M14 (pico) and M15 (manual) as good as can be done by eyeballing tomorrow.
The cables that Arnaud and I checked were:
From satellite boxes:
H1:SUS-BSC9-ETMX-1
H1:SUS-BSC9-ETMX-4
H1:SUS-BSC9-ETMX-7
H1:SUS-BSC9-ETMX-16
H1:SUS-BSC9-ETMX-19
H1:SUS-BSC9-TMONX-1 This was the only bad one, the rest are fine.
H1:SUS-BSC9-TMONX-4
ISC stuff:
QPDs (red H1:ISC_X9-1, green H1:ISC_X9-2)
Picomotors H1:ISC_X9_82
beam diverter H1:ISC_X9-14
Pico pictures, TMXS. Though you cannot tell from the pictures, kapton washers are on all picos.
First: M6, collars installed on both.
Second: M3 (closer to the edge) and M4. There was not enough space for a collar for M3 YAW.
Third: M14, there was not enough space for a collar for PIT.