More details coming, but Fil, Gerardo and I spent most of today rebuilding the ITM ESD feesthru connectors to the latest rev. This involved pulling it from the feedthru on the inside of the chamber port, cut the connector off the 5-way cable, strip and recrimp pins, and reassemble inti a new connector. We had a few failed attempts on the ITMY set but finally figured it out.
We also found the 5th (LL quadrant) pin at the CP on ITMX not well seated in it's connector which caused us some grief. We eventually just squeezed the inner pin to make it work since we cannot fix this in any other way. The continuity checks then passed.
TBC...
ITMX/Y ESD Feedthru Retrofit
1. Cables cut from old ESD connector.
2. Continuity test was done on each pin to verify each section LR, UR, BIAS, UL, and LL.
3. The in-vacuum cable was re-terminated for installation of the new UHV 5-way coaxial connector.
4. Pins and shields were checked for isolation to chamber.
Pin layout for ESD (@ Feedthrough) is as follows:
Pin 1 - LR
Pin 2 - UR
Pin 3 - BIAS
Pin 4 - UL
Pin 5 - LL
Following E1400430, Pin 1 is slightly offset in spacing from the other pins. New feedthrough has a one to one pin layout (pins are not flipped inside flange). Pin 1 with the offset in spacing is the same both in-air and in-vacuum.
I had a little time to investigate the seemingly inadequate purge-air issue after the in-chamber folks were done for the evening and all of the soft covers were on. Nothing definitive was determined but perhaps one clue was added. I'll need to have a second person to confirm (one in LVEA and one at the Kobelco) but tonight it seems that the frequency of "low flow" is greater than the drying tower switching frequency. If so, my original observation was wrong. For tonight, I increased the pressure setpoint at which the compressor loads from 80 psi to 90 psi.. This will only help if the issue isn't drying tower dependent. Chandra and I should be able to investigate tomorrow but we may need to shut off the system. As an aside, I noticed that none of the lights are working on the HAM1/HAM2 or HAM3 clean rooms? Both appear to be plugged in and, for the case of the HAM3 clean room, the breaker isn't tripped.
ECR1700056, WP7245
Hugh, Jim, Rich M, Dave:
I have ported the perl scripts storeCartBiasTargets.pl, setCartBiasSetpoints.pl to new python scripts (storeCartBiasTargets.py, setCartBiasSetpoints.py). The new scripts take exactly the same arguments as the original scripts, so no changes to the calling systems are needed.
Hugh and Jim allowed me to test my code on H1 ISI ITMY ST1 this afternoon.
In the old system, the 'set' command was called from MEDM (ISI_CUST_CHAMBER_ST1_BIAS.adl) within an xterm calling a wrapper shell script, while the 'store' command was called directly. The xterm allowed any errors from the script to be displayed.
In the new system, both commands are called via an xterm window calling a wrapper shell script (storeCartBiasTargetsWrapper.sh was created for this purpose). The new scripts perform more error checking and user feedback which is shown in the xterm.
After testing on H1 ISI ITMY ST1, I restored all the settings back to their original values (using a ramp time of 5 seconds). The new code is now ready for rollout on all ISI systems.
I have created a Work Permit (WP7245) to cover the MEDM changes and further testing.
J. Kissel, S. Pai I've processed the results of using the B&K hammer accelerometer system to characterize the resonances of the support structure for the TCS Steering Mirrors in BSC2 (SM 2, D1101851). These have been of concern after Robert identified them as potential scattered light sources in LHO aLOG 39290. Since, they've had standard SUS vibration absorbers (D1002424) installed to help reduce the Q of their resonant features (see preliminary testing at T1700535). We have no before-vibration-absorber data other than Robert's spectrograms, but I attach the new results with vibration absorbers installed. I also attach a crude screenshot comparing these results against Robert's spectrograms, and the resonant features roughly line up. #sanitycheck The results show that, while the majority of the resonant features *above* 30 Hz have a nice low Q, there remains a feature at 25.62 Hz (for TCSY's mirror) and 20.88 Hz (for TCSX's mirror) that is still particularly high Q. Edit -- I attach a zoom of these ~25 Hz resonances, as well as the raw data and a script written to analyze it.
Cheryl & Ed are continuing IO work at HAM2 past 16:00.
Ed and I have exited the LVEA. IO alog will be entered from home.
For tomorrow, we will need to swing the ITMy ACB back into its nominal location such that we can recover our only ACB swing back wedge (the second wedge we borrowed from LLO was returned earlier this month). Swing back ITMx ACB and apply spray FC and "pizza crust". Finish out BS ground loop checks and start ITMx ground loop checks.
I wrote a python script (userapps/release/cds/common/scripts/delete_daq_empty_files.py) which will delete any zero sized gwf or md5 files in the current directory. It defaults to 'dry run' mode (lists files which would have been deleted).
I ran this on h1fw1's 11970 and 11969 directories for full, second and minute files to clean the file system up after Sunday's disk filling event.
This morning I completed the weekly PSL FAMIS tasks.
HPO Pump Diode Current Adjust (FAMIS 8452)
With the ISS OFF, I adjusted the operating current of the HPO DBs. The changes are summarized in the below table, I also attached a screenshot of the PSL Beckhoff main screen for future reference.
| Operating Current (A) | ||
| Old | New | |
| DB1 | 53.2 | 53.4 |
| DB2 | 55.0 | 55.2 |
| DB3 | 55.0 | 55.2 |
| DB4 | 55.0 | 55.2 |
I did not adjust the operating temperatures of the DBs. The HPO is now outputting 155.4 W and the ISS is back ON. This completes FAMIS 8452.
PSL Power Watchdog Reset (FAMIS 4023)
I reset both PSL power watchdogs at 16:55 UTC (8:55 PST). This completes FAMIS 4023.
Attached is the running trend of diode box current increaes since we started weekly adjustments. The large increases required at the end of November seem to have leveled off back to the more normal 0.2 A weekly increase. We are continuing to monitor this.
The LVEA has transitioned to LASER HAZARD.
Tweaked the alignment into the reference cavity. The transmission went from being ~0.83 to 2.63. Most of the adjustment was in the
vertical. The mirror at the bottom of the periscope was adjusted so that the reflected beam moved "up" on the camera view, this
corresponded to "loosening" the pitch adjustment.
Replaced the 45 MHz EOM driver. Old S/N S1500118. New S/N S1500117.
Cable length of 45 MHz signal from the EOM SMA connector to the EOM driver (D0900760) N connector is ~84 inches.
To facilitate cleaning around HAM4 and the HAM4 cleanroom, I have transitioned the LVEA this morning to LASER SAFE.
Bypass install was effected by changes in IM1 and IM2, so second bypass mirror is removed, and alignment into the IMC is under way. Beam is reaching MC3 and MC3 Trans irises, and there's still some fine tuning to do to complete the MC1 to MC2 path. Once the IMC is flashing, and IO is aligned to PR2, the second bypass mirror will go back in for the ISS array, and IM4 Trans, alignments.
LVEA remains Laser Hazard.
Both doors are on HAM 5 and bolts tightened, the south door is on HAM 6 with 4 bolts. The clean room that was over HAM 4 is now located over ION pump 4. That area will be cleaned by the cleaning crew tomorrow a.m.
There is a type 6 mass (the largest D071200) on the +Y face of the ISI wall in HAM5. And it is not coming off. See the photo and know that the large nozzle heading toward the OMC tube is too close to let the mass clear the four pins on which it hangs. A type 5 mass (~half the thickness of a 6) should clear but not the T06. We should probably avoid doing this in the future, if we have a chance.
Vacuumed in HAM2, using this combination of vaccum hoses:
The Kapton tube was class-A, so I used it to vacuum horizontal surfaces in MC3, MC1, PR3, IM1, and IM3 cages, and I did use it in contact with the metal.
I kept close track of the space under the +Y MC3 blade spring, and from this test area I can see that larger particulate are picked up by the vacuum, but smaller particulate are not, and when I wipe with a IPA wipe, the small particulate are removed. Picture attached.
I put IM1 on EQ stops and used the vacuum to remove a large particle on the upper portion of the face of IM1, and this was successful without any contact between the optic and the Kapton tube.
I used the same technique to remove large particulate from the MC REFL periscope 2 lower mirror, which was very contaminated. Not all of the particulate that I could see would come off of the optic, so some may be scratches that have been present since install.
Given my conclusion that vacuuming leaves small particulate, I wiped over all of the surfaces that I could reach in HAM2 from both the West and East doors.
PRM stage M2 has OSEM flags on the HR side of the tower that do not go into OSEMS, and the -Y flag has shifted out of place, and will need to be restored.
The really big story is that IM1, IM2, and IM3 shifted in alignment between 50 and 1500urad, and I have only one explanation for this, which is that the 4 8/32 bolts that hold the top plate to the side plates are loose, and will need to be tightened.
These bolts are covered by the brackets that hold the blade spring EQ stops at the top of the tower, so the brackets will need to come off to give access to the remaining 4 loose bolts.
This also reveals that the root cause of the shift I saw in IM3 after the B&K, a shift I recreated myself by tapping with a dog clamp on the top plate, are these 4 hidden loose bolts.
IMAGES FROM HAM2:
IMAGES FROM HAM2:
IMAGES FROM HAM2:
IMAGES FROM HAM2:
Opened FRS Ticket 9573. Note, however -- while we agree that alignment pins in the cage (as suggested in the FRS) would do well to remove the slop described -- after further investigation Cheryl found much more success in relieving the pitch adjustment screws and re-engaging them on IM3. The guess is that they had been over stressed, warping both the top plate under discussion among other things. Not a solid case, but IM3 cage / OSEMs no longer moves / move when you look at it wrong.
(Peter K, Gerardo M)
All dog clamps holding the OFI spacer were re-torqued, due to finding one dog clamp loose.
AOSEMs were set on brackets and positioned to be close to center (per MEDM screen), all fastening components were tighten, set screws and adjustment collar screw, to hold them in place.
Next step is to run a transfer function to determine damping.
J. Kissel Transfer functions look great: - Suspension looks free - Resonances are in the same place as they were before - DC gain looks the same - Qs of resonances are only slightly reduced, no danger of over-damping. I'll take it! Data lives here: /ligo/svncommon/SusSVN/sus/trunk/OFIS/H1/OFI/SAGM1/Data/ 2017-12-06_0012_H1SUSOFI_M1_WhiteNoise_L_0p01to50Hz.xml 2017-12-06_0012_H1SUSOFI_M1_WhiteNoise_T_0p01to50Hz.xml 2017-12-06_0012_H1SUSOFI_M1_WhiteNoise_Y_0p01to50Hz.xml (not that it's still programmed for using OM1 as the readout chain. Eventually we'll have legit templates.)
For the record, attached are the OSEM inputs showing the new offsets/gains for these AOSEMs.