Displaying reports 46381-46400 of 84797.Go to page Start 2316 2317 2318 2319 2320 2321 2322 2323 2324 End
Reports until 16:37, Monday 27 November 2017
H1 TCS
thomas.shaffer@LIGO.ORG - posted 16:37, Monday 27 November 2017 - last comment - 16:37, Monday 27 November 2017(39533)
HWS Power Supply Ground Loop

F. Clara, R. McCarthy, T. Shaffer

Work corresponding to FRS4559.

Summary: While we did manage to isolate the cameras from their base, the grounding problem still exists.

DetChar noticed a noisy source that turned out to be a grounding issue with the HWS cameras. The above FRS was filed and then T1600449 was created as a solution that LLO had found to isolate the camera. Just as T1600449 outlines, the camera base position was marked with some spare clamps, I then disconnected and removed the camera from the base, and then I laid the Kapton on the base. Reassembling this assembly required the use of a nylon 1/4"x20 0.5" screw to hold it from the bottom, and a removal of all other metal hardware. While I worked on this, Fil connected the shield to the Hirose connector. Once we were done, we plugged everything back in and tested it. No good. We double checked our work and couldn't find a source that might cause the grounding, so we unplugged the camera and made sure that it was actually isolated. It was. The LLO alog30372 said that they only checked it was isolated while it was unplugged. So we went hunting.

Fil poked around some more and then called in some backup from Richard. The three of us taped up the bottom of the power supplies where they contact the metal bars that hold them up inside the table enclosure (see attachments). This also did not work. Some more hunting from Richard found that the photo detectors were also grounding to the table, and possibly other sources. We could choose to find all of these sources and find a way to isolate them all, but for today this was where we ended. Tomorrow we will head to the ends to continue T1600449.

Attachments are: HWSY shown with position clamped and Kapton on, a taped base, and HWSX final.

 

Images attached to this report
Comments related to this report
thomas.shaffer@LIGO.ORG - 16:37, Monday 27 November 2017 (39534)

Pictures of the power supplies taped up.

Images attached to this comment
H1 TCS
filiberto.clara@LIGO.ORG - posted 16:34, Monday 27 November 2017 (39532)
HWS Cameras - Grounding Isolation

WP 7222
FRS 4559

Modified HWS camera mounts to isolate grounding per T1600449 and D1200566.

1. HWS camera positions were marked before disconnecting
2. Kapton tape was used between camera and base
3. A nylon screw was used to hold both together
4. Camera was tested for isolation to table without any cables connected. Power cable was modified per D1200566.
5. HWS breakout chassis and Polarization PD whitening chassis were isolated from table with kapton tape

Camera tested good (isolated ) with no cables connected.

F. Clara, T. Shaffer

H1 General (CDS)
filiberto.clara@LIGO.ORG - posted 16:22, Monday 27 November 2017 (39531)
New Illuminator installed on BSC2

WP 7231

LED chamber illuminator was replaced with new modular LED light. End stations will be replaced later this week.

H1 General
jeffrey.bartlett@LIGO.ORG - posted 16:00, Monday 27 November 2017 (39530)
Ops Day Shift Summary
Ops Shift Log: 11/27/2017, Day Shift 16:00 – 00:00 (08:00 - 16:00) Time - UTC (PT)
State of H1: Unlocked - Vent
Intent Bit: Engineering
Support: N/A
Incoming Operator: N/A
Shift Summary: Continuing vent work
 
Activity Log: Time - UTC (PT)
16:00 (08:00) Start of shift
17:00 (09:00) Vent planning meeting in CR
17:41 (09:41) Filiberto – Going to install illuminator at BS2
17:55 (09:55) Terry – Going to Squeezer Bay
17:56 (09:56) Cheryl – Going to HAM2/HAM3
18:00 (10:00) Dave – Working on FW1 problem
18:02 (10:02) Nutsinee – Going to Squeezer Bay
18:15 (10:15) Jeff K. – Going into the LVEA
18:17 (10:17) Betsy – Going into LVEA for alignment work
18:22 (10:22) Travis – Going into LVEA for Viewport work
18:49 (10:49) Peter – Going into the Optics Lab
19:09 (11:09) Travis – Out of LVEA
19:33 (11:33) TJ – Going into LVEA to electrically insulate HWS cameras
20:06 (12:06) Richard – Going to talk with Filiberto in the LVEA
20:10 (12:10) Richard – Out of the LVEA
20:12 (12:12) TJ – Out of the LVEA
20:33 (12:33) Hanford Emergency Broadcast/Notification alert
21:13 (13:13) TJ – Going into the LVEA
21:14 (13:14) Travis – Going to BSC2 to install vibration absorbers
21:26 (13:26) Betsy – Out of the LVEA
21:30 (13:30) Jeff K., Keita, & Sheila – Out of the LVEA
22:18 (14:18) Peter – Going into the Optics Lab
22:21 (14:21) Richard – Going into LVEA to help Filiberto at HWS table
22:30 (14:30) Richard – Out of the LVEA
22:40 (14:40) Keita, Betsy, Cheryl, & Jeff K. – Into LVEA to continue alignment work
23:12 (15:12) Peter – Out of the Optics Lab
23:28 (15:28) TJ & Filiberto – Finished in the LVEA
00:00 (16:00) End of Shift
 
LHO VE
kyle.ryan@LIGO.ORG - posted 15:51, Monday 27 November 2017 (39529)
Measured dewpoint of LVEA purge air to be -28C
I've been measuring this, at least once per week, but haven't always made a log entry.  
H1 PSL
jeffrey.bartlett@LIGO.ORG - posted 15:32, Monday 27 November 2017 (39528)
PSL Weekly Status Report


Laser Status:
SysStat is good
Front End Power is 35.76W (should be around 30 W)
HPO Output Power is 153.0W
Front End Watch is GREEN
HPO Watch is GREEN

PMC:
It has been locked 9 days, 8 hr 47 minutes (should be days/weeks)
Reflected power = 23.77Watts
Transmitted power = 48.68Watts
PowerSum = 72.44Watts.

FSS:
It has been locked for 2 days 3 hr and 28 min (should be days/weeks)
TPD[V] = 2.294V (min 0.9V)

ISS:
The diffracted power is around 2.3% (should be 3-5%)
Last saturation event was 6 days 6 hours and 12 minutes ago (should be days/weeks)

Possible Issues:
PMC reflected power is high

 

H1 CDS (SUS)
david.barker@LIGO.ORG - posted 14:55, Monday 27 November 2017 - last comment - 19:04, Monday 27 November 2017(39527)
PR3 SUS rings up and Software Watchdog trips

FRS9496

Jeff K, Richard, Dave:

At 07:30 PST Thursday 23rd November (Thanksgiving Day) PR3 rang up over two minutes. The T3 top OSEM shadow sensor RMS exceeded the 110mV threshold for 20 minutes continually, which caused the IOP Software Watchdog (SWWD) to DACKILL the h1sush2a DACs, at which time the oscillation stopped. The h1sush2a system remained in this state for the rest of the holiday weekend until the SWWD was reset this morning. Within an hour the ring-up occurred again. This cycle has repeated itself several times today. Investigation is continuing and an FRS has been opened.

Attached plot shows a 30 minute second trend plot of the Thursday morning event. Data shown is:  T3's shadow sensor ADC channel (Ch 3), the h1suspr3 T3 DAC drive (Ch 9) and the h1susauxh2 M1 T3 Voltmon. As can be seen, the OSEM shadow sensor and the model drive ring up in Unisom, driving the coil driver. After the SWWD trips the DACs at the 20 minute mark, the coil driver is quickly zeroed, which causes a bumpy ring-down of the shadow sensor (which the model's output mimics).

Images attached to this report
Comments related to this report
jeffrey.kissel@LIGO.ORG - 18:31, Monday 27 November 2017 (39537)
Open FRS Ticket 9497.
jeffrey.kissel@LIGO.ORG - 19:04, Monday 27 November 2017 (39539)CDS, DetChar, OpsInfo, SUS
PR3 Damping goes unstable because the Top Mass (M1) T3 binary IO switch for its analog low pass is stuck with the filter ON, implying the relay has became suddenly de-energized at 15:30 UTC (07:30 PST) on 2017-11-23. It has remained stuck there since.

Logic thread that got me there:
(1) The L, T, and Y damping loops (composed of LF, RT, and SD sensor/actuators) work just fine. Turn any one of the V, R, or P loops on, and they eventually (over the course of 1 to 2 minutes) ring up and cause the software watchdog to trip.
(2) Had the binary IO screen open, just to show Siddhesh how they work. Noticed T3 was in the wrong state.
(3) Toggling the state request (H1:SUS-PR3_BIO_M1_STATEREQ) from 1 (analog low pass OFF) to 2 (analog low pass ON), changes all the 6 OSEMs to be in the low-pass ON state. In this state, the digital compensation matches the analog configuration, so all is normal w.r.t. the damping loop plant. This is the configuration we ran in for the rest of the afternoon without problem. 
(4) Now, having a little time to think, I realize: when in state 1, the T3 OSEM's analog filtering is still stuck with its low pass ON, but the digital compensation compensates for the low pass OFF state. This changes the damping plant for *one* of the OSEMs, which is involved in all three, V, R, and P loops, and causes the loop to be unstable.

Concluding theory as to what happened:
The triple-top circuit diagram D0902747 (pg2, a zoom of the relevant portion of the circuit is attached for convenience) shows the energized (+5V to the relay, a binary, digital 1 sent through the BIO card) configuration, which is the low-pass OFF condition. When power is lost, the switch flipped to the de-energized (0V to the relay, a binary, digital 0 sent through the BIO card) configuration, which is the low-pass ON. This is what I think happened Thanksgiving morning: the relay (due to analog electronics failure) failed, switching the analog circuit to low-pass ON with the digital compensation still compensating for the low pass OFF condition, V, R, and P damping loops when unstable, rings up the suspension, eventually tripping the Software Watchdog.

I'll update the FRS ticket and let the analog CDS team to put it on their "to-fix" list.
However, because we can happily run in state 2, I don't suggest we take the time to fix it until we're done with IFO alignment, unless it can be fixed some morning quickly before the team gets started.

For now, I've left PR3 in STATE 2, with the damping loops ON.
Images attached to this comment
H1 TCS
travis.sadecki@LIGO.ORG - posted 14:54, Monday 27 November 2017 (39526)
Vibration absorbers installed on BSC2 TCS gold steering mirrors

Title pretty much sums it up.  Photos attached for your viewing pleasure.

Images attached to this report
H1 DAQ (CDS)
david.barker@LIGO.ORG - posted 14:46, Monday 27 November 2017 (39525)
DAQ issues Sunday and Monday Morning

Two DAQ issues happened over the past 24 hours:

At 10:31 Sunday 26 Nov PST, the new E18 RAID on h1ldasgw0 became full. I thought I had more time to start the wiper code and was refactoring it. I manually cleared some space and will run the old wiper for now.

At 05:20 the DAQ data concentrator (h1dc0) crashed. It had been running for 208 days 18 hours, and crashed because of the 208.5 days issue the old 2.6.35 kernels have. We plan on upgrading to a modern kernel before the next 208.5 days expire. The DAQ acquired no data between 05:20 and 10:11 because of this issue.

H1 General
jeffrey.bartlett@LIGO.ORG - posted 10:10, Monday 27 November 2017 (39523)
09:00 Meeting Minutes
   The week of 11-27-17 is dedicated to wrapping up and closing out the work underway in the corner station, with the intention of pumping down over the Christmas break.
WARNING: DO NOT WET WIPE THE NEW BAFFLES. Wet wiping will damage baffle surface. The baffles must be vacuumed and/or dry wiped.
 
Mon:    Finalize alignment between HAM2 to HAM6
           OFI alignment
 
Tues:    Close out of IO alignment work
            HAM5/6 payload and alignment
            B&K Hammering
 
Wed:    Beam and Baffle alignment
            ISS alignment check
            B&K Hammering
            SEI transfer functions
 
Thur:    B&K Hammering
            TCS table alignment
            Finalizing alignment
 
Fri:       BSC2 payloading and alignment
            First Contacting Optics
            Cleaning and prep for door install
H1 PSL
edmond.merilh@LIGO.ORG - posted 08:33, Monday 27 November 2017 (39521)
PSL Weekly Report - 10 Day Trends FAMIS #6176

Everything looks nominally ok. The humidity spikes are curiously sharp on the 24th.

Images attached to this report
H1 ISC (INS, ISC, SQZ)
keita.kawabe@LIGO.ORG - posted 20:06, Wednesday 22 November 2017 - last comment - 15:02, Saturday 25 November 2017(39518)
OFI SQZ path mostly done for now (TJ, Gerardo, Jenne, Sheila, Keita)

OFI was realigned by Gerardo. Irises on HAM6 were put in place by TJ.

We installed a temporary HWP on OFI.

The beam was first centered on the steering mirror on OFI closer to ZM2 by using the other steering mirror on OFI. The centering accuracy is not good but it's not that important.

Then the beam was centered on ZM2. Centering accuracy I would say is a mm or so.

We rotated ZM2 so the beam is centered on the HAM6 iris closer to VOPO (i.e. more important one) for YAW. Fortunately the PIT was already about right, we didn't have to rebalance ZM2. All PIT fine adjustment was done using one of the steering mirrors on OFI.

Only after the beam was centered on the HAM6 iris closer to VOPO, we moved the second HAM6 iris in place and centered the iris without touching the beam.

The beam dump to catch the septum window reflection was roughly adjusted by eyeballing. Unfortunately it was impossible to see the AR reflection using IR viewer and a card, so instead I looked at the reflection of the ZM2 mirror outline on the septum window while positioning my eye on the line connecting the IR beam position on the septum and the apex of the V of the beam dump. The power coming to sqz path is like 300uW as of now, AR reflection should be much smaller than uW. Maybe we can increase the power to 10W (a factor of 40 increase) and see the beam.

Sheila and Jenne measured the power of the beam in the main sqz path using a power meter.

On OFI between M1 and M2 steering mirror 286 uW
Before 1st iris (closer to HAM5) on HAM6 288 uW
After 2nd iris (closer to VOPO) on HAM6 276 uW

ZM2 and beam dump dog clamps are not super tight as I wasn't able to find the right tools. They need to be tightened and after that we need to confirm that the beam still comes through both of the irises.

Pictures to show the positions of ZM2, beam dump and two irises will be posted later.

Comments related to this report
keita.kawabe@LIGO.ORG - 15:02, Saturday 25 November 2017 (39520)

1: HAM6 iris closer to VOPO.

2: HAM6 iris closer to HAM5.

3: ZM2.

4: ZM2 viewed from the front.

Images attached to this comment
LHO VE
kyle.ryan@LIGO.ORG - posted 18:43, Wednesday 22 November 2017 (39517)
1840 hrs. local -> made small adjustments to purge air in LVEA


			
			
H1 AOS (AOS, SQZ)
gerardo.moreno@LIGO.ORG - posted 17:10, Wednesday 22 November 2017 (39516)
HAM5 OFI Update

Beam is centered on the input and output irises, I stopped at that point to allow Sheila and Keita to continue with the squeezer path.

Cage still needs some dog clamps, currently it has 3 holding it in place, input baffle needs to be replaced, AOSEMS need to be installed and damping needs to be revisited, table had to go up to center the beam on the apertures, thus changing the damping behavior.

Note about the output baffle, the beam is close to the -X side of the aperture.  I will post a photo as one comes available.

LHO General
thomas.shaffer@LIGO.ORG - posted 16:00, Wednesday 22 November 2017 - last comment - 16:24, Wednesday 22 November 2017(39507)
Ops Day Shift Summary

TITLE: 11/22 Day Shift: 16:00-00:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
SHIFT SUMMARY: Sheila, Nutsinee, and Terry still out in the SQZ Bay. Gerardo still tweaking OFI.
LOG:

Comments related to this report
gerardo.moreno@LIGO.ORG - 16:24, Wednesday 22 November 2017 (39515)

I'm done tweaking the OFI Alignment for the day.

H1 SYS
betsy.weaver@LIGO.ORG - posted 17:10, Tuesday 21 November 2017 - last comment - 09:53, Monday 27 November 2017(39501)
La La alignment land

Following on from Keita's alog from yesterday, we spent all day attempting to convince ourselves that the SR chain of optics are hanging symmetrically within their structures, using little to no tooling.  Holding rulers up to various optics and structures, and painstakingly logging measurements, I could not find any reason to believe that the beam centering we've done between the center of SR2 and SRM is out by more than ~2mm.  The PSL beam line that we have set between the center of SR2 and SRM looks good to carry on.  Indeed, this may mean that the baffles do not look symmetric on the structures, but at least the beam path appears correct.  We'll revisit baffle positions an drawings tomorrow.

Meanwhile, since I was wandering the tube between HAM4 and HAM5, I took a look at the beam centering going through the newly built SR2 scraper baffle D1003300.  At first I was thrown off by the fact that the beam seemed to go through the baffle off center even though the baffle was installed using a template which I would have thought set it pretty close (within mm's).  A lunch break consult with Keita and Calum pointed out that the beam I was looking at was only the SR3-to-SR2 beam which straddles the centerline of the baffle ellipse hole with the SR2-to-SRM beam which is hard to spot when viewing the SR3-to-SR2 beam with an IR card.  A quick calculation, and a SW confirmation told us the 2 beams should be separated by 20mm and should straddle the centerline.   Now how to find the center of the hole while standing in the dark with a viewer card and not occulting the beam with your body...  I gave up trying to measure in-situ and instead opted for some pictures to scale.

Attached is the PDF scaled pic I used - I'm not spending any more time screwing around with the oddities of why the font is miniscule - what I did was:

- Scale the aperture in the picture to the 161mm dimension I read off the drawing D1003301 (for what ever reason Adobe makes starts the scale at a huge setting like some 40 inches or so)

- Using the new scaler, measure to the beam center shown in the picture

- 161mm /2 = 80.5mm is where the center of the aperture should be, so the beam center should be left of that by 10mm (half of the 20mm), 90mm.

- The beam is at 87.4mm.  Of course it's hard to estimate the beam center since the beam is ~20-30mm in diameter, fuzzy, and moves a bit.  I'd estimate the error of my ability to measure this centering to better than 5mm...  Feel free to redo.

Seriously, please let that be close enough.

 

I did however, take a picture of what can be seen from the plane of the MCTube Eyeball baffle closest to HAM4 on the beam path (see below).  Not sure I was able to place the camera on the beam line very well...  I can confirm that everything shown in the left lobe cutout of the baffle is in dead all HWS silver mirror reflections (and no metal from mounts).  It's hard to tell if there is a sliver of the right side of the SR2 optic still in the right portion of the right aperture lobe.  Maybe it's the angle of my camera view.  Dunno.

 

Images attached to this report
Non-image files attached to this report
Comments related to this report
betsy.weaver@LIGO.ORG - 09:53, Monday 27 November 2017 (39522)

A consult with Calum who agreed that this alignment is good.

H1 CAL (CAL)
aaron.viets@LIGO.ORG - posted 19:02, Sunday 19 November 2017 - last comment - 11:27, Saturday 25 November 2017(39480)
gstlal calibration pipeline resampler fix for C02
I have added new features to the element lal_resample used in the gstlal calibration pipeline so that it can perform upsampling for the actuation equal in quality to the old gstreamer (version 1.4.5) resampler. The upgrade to gsteramer-1.10.4 on the clusters introduced a ~2% systematic error in the C01 frames from ~50 Hz to ~1 kHz during the month of August. See, e.g.,
https://ldas-jobs.ligo.caltech.edu/~alexander.urban/O2/calibration/C00_vs_C01/H1/day/20170802/

The change made was the addition of a sinc table filter in the upsampling routine. Several tests were done, and plots are attached:

The first two plots show the filter's response to a series of impulses separated by 4 seconds. This input data was upsampled from 128 Hz to 1024 Hz. The first of these plots shows 30 seconds of data, and the second is a close-up on a single impulse.
The 3rd plot is a 10-second sinusoid upsampled from 8192 Hz to 16384 Hz.
The 4th plot is a 30-second stream of ones upsampled from 128 Hz to 1024 Hz. The apparent thickness of the line indicates the amount of digital error, of order ~10^-8.
The 5th and 7th plots are ASD comparisons between the output produced by the calibration pipeline using this new resampler and the C00 frames from August.
The 6th and 8th plots are ASD comparisons between the output produced by the calibration pipeline using this new resampler and output pruduced with no resampling at all (i.e., all actuation was filtered at 16384 Hz). I suspect the wiggle above 1 kHz is due to a ~2% contribution from the actuation that is lost in downsampling to 2 kHz for the filtering.

For information on filters to be used for C02 production, see
https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=39419
https://alog.ligo-la.caltech.edu/aLOG/index.php?callRep=36707
Images attached to this report
Comments related to this report
aaron.viets@LIGO.ORG - 11:27, Saturday 25 November 2017 (39519)
[Greg Mendell, Maddie Wade, Aaron Viets]

Greg's tests revealed problems with the new gstlal-calibration code that were not present in the old versions, producing error messages like:

*** Error in 'python': munmap_chunk(): invalid pointer:
0x00002babb1345780 ***
======= Backtrace: =========
/lib64/libc.so.6(+0x7ab54)[0x2ba8010eab54] ...
...

I've found and fixed two bugs in the new resampler:
1) In certain places, a  pointer to the next output buffer being produced was being incremented (but not dereferenced) beyond the end of the allocated memory of that buffer.
2) There was a particular corner-case where a pointer to where input data from previous buffers was being temporarily stored was being shifted to an incorrect location.

After the fix, I ran the same tests, and they produced identical results. The only difference was that the jobs I found that produced errors no longer produced those errors.
Displaying reports 46381-46400 of 84797.Go to page Start 2316 2317 2318 2319 2320 2321 2322 2323 2324 End