D. Hosken, G. Grabeel, T. Vo We were able to fix the ring heater chassis EtherCAT wiring by referencing the drawings. We initially turned both ITM ring heaters to 30 Watts at 6:46 PM PT but it seems as though the maximum power that the drivers can put out is ~15-16 Watts so we changed the script that Greg wrote to run the power at 13.5 Watts during the high power portion and .5 Watts in the low power portion. I'll come in tomorrow morning to run some trends and take some measurements. John verified in the first hour that there were no spikes in pressure.
It looks like we will need to go in chamber at end X to fins IR on the QPDs. I searched for the beam today by locking ALS, and moving the picomotor for M4 to toward the position that Kiwamu et al found in February (alog 10091). This was fine for the Y direction, but in the X direction I only got about a quarter of the way toward the old position before the green transmitted power started to drop. One theory is that this could be the green clipping on the mount for M4 (TMS table drawing). After a little bit of searching around, I decided move the picomotors back to the position that we had set them to to restore the beam on the table.
The positions used to get IR onto the LSC PD from February until yesterday were 9267 X 1665 Y for M4. Today after moving the picomotor around quite a bit, I needed to use 27357 for X and -12616 for Y to restore the beam to the same position. So these numbers are meaningless as references.
If you remove the snout from the LSC TRX PD in air, there are two brighter green spots (with two very faint spots below them to form a square, right now the lower ones are clipped upstream). The one that is slightly brighter and on the side of the PD face that is closer to the chamber is the one that is co-linear with the IR, and could be used as a reference if we decide to send IR into the chamber from this path to align the QPDs.
Yesterday Daniel noticed that the beam was clipped on EX WFSA, but the beam was not centered either and we were in the middle of IR beam finding. Today I centered the beam and it was still clipped because the beam was coming to the WFS head at much shallower angle than it should be. I fixed it by tilting the WFS head.
I and Daniel went to EY and tested WFSB using AM laser, and we saw that some of the channels were a factor of 5 or so smaller than the others.
Eventually we tracked it down to the WFSB whitening chassis (S1101602) though I thought it was working OK on Thursday (https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=12138),
We tested S1101601 that was pulled out earlier this week that was suspicious unit but was never conclusively diagnosed bad, and it didn't work. So we got another spare unit (S1101638) from the corner station and put it in.
What are in use now: S1101600 for WFSA, S1101638 for WFSB.
Bad units: S1101601, S1101602, S110163.
Bad ones are put on a table in EY.
model restarts logged for Fri 30/May/2014
2014_05_30 14:42 h1fw0
unexpected restart of h1fw0
John Worden, R. Weiss Vibration measurements of the beamtube with the new R10 insulation and aluminum jacket were made and described in the appended document. The new insulation reduces the acoustic coupling to the beamtube but not as well as the initial insulation. The data enables a more detailed estimate of the phase noise from the beamtube motion due to the faulty HR coatings of the new test mass mirrors. The DCC number of the document is T1400384.
Error in the document. Please see T1400384-v2 or LHO log entry 12232
Sheila & Dan We marked the two IM4_TRANS beams (PRM_REFL and IO_TRANS) on the wall of the LVEA today. To be clear: both of these beams are transmitted through IM4. One is from the beam leaving the IMC, the other is the reflection coming back from the PRM. The IO_TRANS beam is in the -X direction on the wall. We noticed that there are also two green beams very close to the IR beam reflected off the PRM. Only the Y-arm was locked at the time, so this must be the faint green reflection off of PR2 from the Y-arm. We might want to use these as a reference for the BS alignment in the future.
(Keita, Daniel)
Today we measured and adjusted the gain/phase of the WFS RF signals. WFS_A looks fine, but WFS_B has segments 3 and 4 which are ~10x smaller than 1 and 2. Engaging DOF4 did result in a stable feedbakc but with a rather large offset. We added an offset to segment 4 of WFS_B to recover. Adding DOF3 did not result in a stable feedback.
Playing around with the individual pit/yaw offsets and the WFS DC centering one can find feedback topologies with all 4 DOFs engaged. However, they are susceptible to disturbances.
For this measurement the WFS offsets are:
Bias | WFS A | WFS B |
---|---|---|
Pitch | -2500 | -1600 |
Yaw | -5000 | 4700 |
First measurement shows an ETMY yaw misalignment by 1 µrad. The power drops by about 15%. The yaw offsets are of order 10,000 counts. We also see a significant pitch ofset. But, more importantly the DC offsets on the WFS heads are also very large. The WFS servo was off during the measurement.
The second plot shows the effect of moving the picomotor for WFS_B by about 0.2 in yaw and 0.3 in pitch. The resulting offsets are of order 7000. Since the WFS servo was off, there was no degradation of the cavity power.
This RGA is set up to scan every 60 minutes for this weekend in order to capture data during the Ring Heater "burn".
Yesterday night, after Richard re-rerouted the end-y ESD cabling, I took a L2L transfer function to check the length drive with the ESD. It seems to behave nicely, and similarly as EX. The attached plots shows the comparison of Ex and Ey TF in m/cts.
The measurement was taken using the same dtt template as for ETMx. The arm was locked without the slow control engaged. Sensor used was ALS-Y_REFL_CTRL (in um). Measurement lives in
/ligo/svncommon/SusSVN/sus/trunk/QUAD/H1/ETMY/SAGL3/Data/2014-05-29_H1SUSETMY_L3_L2LPY_SweptSine.xml
CO2X - Zero-ed out the QPD segments to compensate for the differences in individual quadrants. CO2Y: - Zero-ed out the QPD segments to compensate for the differences in individual quadrants. HWS: - Built up HWS camera for both X&Y sides of the table, able to get serial connection and read out the status information - End station HWS table inventory progress: Cables and optics completely kitted. - Need a re-do of positioning of the HWS-Y camera because of interference with the table enclosure. RH: - Prepared for a 24 hour ITM ring heater test. 30 minutes on full power (~30 Watts) and 30 minutes off. We'll do this work on Saturday and Sunday.
I put together this T1400371 procedure for aligning the 90/10 BS in HAM3. It describes the way they did the alignment at Livingston (Option 1, green beam from HAM1, IOTR table would need to move) and the way that Keita would like to do it here (IR beam from HAM3, no need to move IOTR). All the parts needed are "mostly" ready. Here is a summary: - BS 90/10, post, clamp (mirror is cleaned and installed in mirror mount) - V-shaped dump, post, clamp (ready) - IR laser diode source (in optics lab) - spare clean sled (in optics lab, can be used to mount the laser source and collimator in HAM3, if needed) - 2 spare 2" HR 1064 clean optics (on optics table in OSB optics lab - I left there also a clean 2" HR 532) - Missing: IO style posts for mounting the steering optics (Corey and Cheryl working on it)
Operators Log 05/30/2014 Day Shift Summary LVEA Laser Hazard 08:49 Filiberto – To End-Y working on cable repairs 09:00 Kyle - Moving RGA cart to BSC7 area 09:00 Hugh – Working on external cabling at HMA5/6 09:35 Dave & Thomas – Working on TSC-X and Hartman tables 09:45 Rite Choice on site to pick up pallets and scrap wood 10:04 Keita & Sheila – Going to End-X 10:06 Kyle – Going to End-Y to recover test equipment 10:45 Betsy & Travis – Working in the West Bay cleanroom 12:49 Karen – Going to End-Y 13:08 Betsy & Travis – Working in the West Bay cleanroom 13:17 Dave – Working on TCS-X and Hartman tables 14:18 Karen – Back from End-Y 15:22 Betsy & Travis – Out of the LVEA
Arnaud may run some measurements on the SUS in HAM5 so I delayed these to start later today. Running on OPSWS8
When the septum was removed, the cabling between HAMs 5 & 6 were disconnected so the crew could deal with all the bolts. I asked FClara to reconnect the cables to the WHAM6 NW feedthru, SUS & ISC I think. I'm not familiar enough to distinguish these so I left those to him. When they are sorted out I will complete the cable/feedthru protecting. Meanwhile, HAM5 ISI sensors are live, don't disconnect any cabling, you'll have to cut zip ties to do so.
Installed SUS and ISC cabling to D3 flange of HAM6 (NW corner). Flange Cable Description D3-1C1 H1:SUS_HAM6-10 OMC TOP D3-1C2 H1:SUS_HAM6-11 OMC Right/Side D3-2C1 H1:ISC_HAM6-265 ASC_AS_A (WFS) D3-2C2 H1:ISC_HAM6-266 ASC_AS_B (WFS) Document D1300122, internal in-vacuum cabling calls out for cable ISC-265 and ISC-266 to be connected to flange D5-3C1 and D5-3C2. Document should be updated. Filiberto Clara
HAM6 NW Cables stress relieved and E-FeedThrus protected.
In preparation for the vent, I centered POP QPDs so that we can use it as an alignment reference when we will install HAM3 beam splitter.
Right now both POPA and POPB PIT and YAW are all within +-0.015.
QPDA sum is 56.3, QPDB 51.7 using straight shot.
POPA picomotor counts are: X -331, Y -28257.
POPB picomotor counts are: X 4151, Y 20661.
Not unlike TMS picomotors, these are sort of degenerate. You can use pico B to center QPDA, then pico A to center QPDB, and repeat thousands of times to eventually have a good centering. You can also overshoot repeatedly to make it quicker. For example, when QPDB is too low while QPDA is centered, you use pico A to bring QPDB up, then pico B to bring QPDA down, and repeat.
The sled is sensitive to even 1 step of the picos. Medium step (100 steps) is safe to use without worrying too much about losing the beam, but if you want to use Large (1000 steps), be prepared to lose the beam on both of the QPDs.
Travis, Betsy
Over the last few days, we assembled an upper structure which will eventually attach to one of the ITM lower structure that is currently trapped in chamber. We finished assembling the 4 top stage blade cartridges and 2 top masses for this unit. We then mounted all of them plus top wire segments and parts of the table cloth to the upper structure. We will mount the whole cube to the test stand on Monday and then it will wait for it's other 2/3.
Thomas, Jim, David and Dave
We were able to establish serial communications between the h1hwsmsr computer in the MSR with the HWS Teledyne Dalsa Pantera 1M60 camera on the X-arm TCS table in the LVEA. We suspect communications were not working earlier due to serial synchronization problems, which were cleared when the remote transceiver (RCX CLink) and camera were power cycled. We discovered several MEDM/Beckhoff/Wiring issues with the power control of these devices which Thomas is going to resolve over the next few days.