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Reports until 09:26, Wednesday 02 November 2016
LHO General
patrick.thomas@LIGO.ORG - posted 09:26, Wednesday 02 November 2016 (31126)
Morning meeting notes
Weekly site wide meeting at 3 PM local.

SEI
Jim W. recentered BRS at end Y
Hugh was not able to complete guardian change for HEPI pringle mode DOF (WP 6286). Changes reverted. Will consult with TJ.
Operators should take note of Jim's alog regarding SEI configuration.

TCS
Nutsinee reported in an alog that the temperature channels for both TCS laser channels are glitching.

EE
Working on remote access to newly installed Beckhoff safety terminals.
Bad Beckhoff module replaced in corner chassis 3.

CDS
Tried to install an additional ADC card for PEM in the h1oaf IO chassis. Doing so prevented booting even to the BIOS screen. This glitched all of the models on the dolphin network. The ADC card was removed and the front end models restarted. No changes were made to the models on h1oaf. Testing the ADC card in the test stand reproduces the same situation.
LLO range is invalid in DMT, being addressed.

PSL
Added polarization minimization.

VAC
Kyle looking for an opportunity to go to end stations.

FAC
Ongoing search for a water leak.
H1 PSL
peter.king@LIGO.ORG - posted 08:06, Wednesday 02 November 2016 - last comment - 08:30, Wednesday 02 November 2016(31121)
injection locking servo transfer functions
Transfer functions measured after circuit modifications made to the injection locking field box.

    The gain voltage setting behaviour does not appear to be correct.
Images attached to this report
Comments related to this report
daniel.sigg@LIGO.ORG - 08:30, Wednesday 02 November 2016 (31122)

probably oscillating for gains <0V, ie., >20dB.

H1 General
nutsinee.kijbunchoo@LIGO.ORG - posted 08:02, Wednesday 02 November 2016 (31119)
Owl Shift Summary

TITLE: 11/02 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC

STATE of H1: Lcok Acquisition

INCOMING OPERATOR: Patrick

SHIFT SUMMARY: Bad. All locklosses tonight were caused by PI 18043Hz (Mode27). See alog31111 and comments therein. There were 6 locklosses total. I didn't keep track of all the lockloss times. None of the modes were PLL locked but only one or two casued trouble. Mode 26 also rung up but was able to damp once I get the BP filter to match the peak frequency. Not as straight forward for Mode 27. 

LOG:

08:50 Lockloss

12:06 CO2X 0.2W --> 0.4W

12:09 Intent bit set

12:25 Intent bit dropped. CO2X Guardian finds lock point

12:32 Intent bit dropped. CO2X Guardian finds lock point

12:37 Lockloss

13:05 NLN. CO2X 0.2W --> 0.4W

13:39 Lockloss. Peter wants to make some measurement with the PSL so I kept the IFO down.

14:34 Peter out

 

Note:

H1 PSL
peter.king@LIGO.ORG - posted 07:57, Wednesday 02 November 2016 - last comment - 08:33, Wednesday 02 November 2016(31120)
pre-modecleaner servo transfer functions
Measured transfer functions after yesterday's circuit board modifications.  The MEDM gain slider
was increased from 0 in increments of 3.
Images attached to this report
Comments related to this report
daniel.sigg@LIGO.ORG - 08:33, Wednesday 02 November 2016 (31123)

I noticed this before, where the gain slider is miscalibrated by a factor of 2. 0dB to 40dB is mapped into +/-10V, but it looks like you only need +/-5V for the full range.

H1 TCS
nutsinee.kijbunchoo@LIGO.ORG - posted 05:42, Wednesday 02 November 2016 - last comment - 21:38, Monday 07 November 2016(31116)
Glitches in CO2 temperature channels

Started yesterday evening. Doesn't seems to be equally spaced.

Images attached to this report
Comments related to this report
alastair.heptonstall@LIGO.ORG - 08:57, Wednesday 02 November 2016 (31124)

It could be pickup through the unshielded part of the RTD cable (where it comes out of the laser), but it's strange that it started in X and Y at the same time.  Can you check the FLIR cameras are turned off on the MEDM screen.

betsy.weaver@LIGO.ORG - 09:07, Wednesday 02 November 2016 (31125)

Apparently there is a "glitch" in the laser power of both X and Y TCS systems every time the Laser power meter sees a request for a power change.  (see 1 day trend with additional channels to correlate with).  However, this did not just start yesterday, it has been going for at least a month (see second plot of the last 3 days).  I spot checked back a month and the behavior is the same.  Note, there are a few extra spikes on these channels but this doesn't seem to be new behavior.

Images attached to this comment
nutsinee.kijbunchoo@LIGO.ORG - 21:38, Monday 07 November 2016 (31299)

Update: I looked closer at these glitches.

 

Characteristic:

A single glitch spans across multiple sample points, lasted a little less than half a second. Almost everyone of these glitches lead by one smaller glitch that's roughly 1.5 second apart, followed by an even smaller glitch and immediately followed by a larger glitch.

 

Timeline:

I looked back several months and it seems like these glitches started to show up much more frequently on May 13th this year (started at 16:28 UTC to be precise). I looked back on the alog and didn't find any invasive work with the TCS on May12th or 13th.

Images attached to this comment
H1 ISC
nutsinee.kijbunchoo@LIGO.ORG - posted 03:30, Wednesday 02 November 2016 - last comment - 06:40, Wednesday 02 November 2016(31111)
Three locklosses now due to PI 18043Hz

I checked to make sure the line and the BP matches. Changing the phase both on the main PI medm screen and on the damping filter doesn't make a different. The PLL green light is on but Shelia mentioned that PLL is not actually locked and I don't know how to make it locked (some other modes with PLL green light indicator also have red PLL lock status). I also tried to zero the gain as Sheila suggested.

Comments related to this report
nutsinee.kijbunchoo@LIGO.ORG - 03:56, Wednesday 02 November 2016 (31112)

Then I found that until Maintenance morning (1 Nov 18:26 UTC to be precise) this mode has been using OMC DCPD as its input signal. It was magically switched to be using TRY QPD. I put the gain back to where it was in the matrices. We'll see how it goes.

Images attached to this comment
nutsinee.kijbunchoo@LIGO.ORG - 04:30, Wednesday 02 November 2016 (31113)

Okay doing that somehow kill the input signal alltogether. I let through the signal from TRY QPD again but zero the damping gain.

nutsinee.kijbunchoo@LIGO.ORG - 04:32, Wednesday 02 November 2016 (31114)

Nevermind. Reverted it. Things became bad real fast as soon as I let through signal from TRY QPD for Mode27.

nutsinee.kijbunchoo@LIGO.ORG - 04:35, Wednesday 02 November 2016 (31115)

And PI broke the lock. This is the 4th lockloss caused by PI tonight.

nutsinee.kijbunchoo@LIGO.ORG - 05:46, Wednesday 02 November 2016 (31117)

And 5th time. The time constant is about the same as previous locklosses so I guess switching input from TRY QPD to OMC DCPD doesn't matter. In fact I couldn't get any signal from OMC DCPD so that's even worse since I have zero chance of damping it. I'm going to try the original setting again but this time alter the gain (which I have also tried).

nutsinee.kijbunchoo@LIGO.ORG - 06:40, Wednesday 02 November 2016 (31118)

And 6th time.

H1 General
nutsinee.kijbunchoo@LIGO.ORG - posted 01:39, Wednesday 02 November 2016 (31110)
Owl Shift Transition

TITLE: 11/02 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC

STATE of H1: Nominal Low Noise/Commission

OUTGOING OPERATOR: Ed

CURRENT ENVIRONMENT: Wind: 16mph Gusts, 13mph 5min avg Primary useism: 0.03 μm/s Secondary useism: 0.29 μm/s

QUICK SUMMARY: Before Stefan left he asked me to make some TF measurement. So I'm going to spend some time doing that before setting the intent bit. Locking went smoothly.

H1 AOS
matthew.evans@LIGO.ORG - posted 00:53, Wednesday 02 November 2016 - last comment - 12:19, Wednesday 02 November 2016(31109)
PMC output makes frequency noise (still)

After today's changes to the PMC servo, which included increasing the loop gain, we noticed a familiar bump around 4.2kHz in DARM.  Lowering the PMC gain from 16dB to 0dB made the bump smaller in DARM (see images).  Given the coherence with REFL9, it seems that this is coupling through frequency noise.

We also made a small exploration around the already good PMC input beam alignment.  This didn't have much impact, but it revealed that small changes in the alignment can change the input offset to the PMC servo.  That is, the offset which maximizes the PMC throughput can be changed with small alignment tweaks. Using this effect, we made a 0mV input close to optimal (see second image).

Images attached to this report
Comments related to this report
jeffrey.kissel@LIGO.ORG - 12:19, Wednesday 02 November 2016 (31135)DetChar, ISC, PSL
Tagging PSL and ISC.
H1 CAL (DetChar)
jeffrey.kissel@LIGO.ORG - posted 00:48, Wednesday 02 November 2016 (31108)
Adjusting CAL Line Heights for Better Uncertainty
J. Kissel

In order to improve the uncertainty on the parameters the lines are measuring, I've adjusted the line heights of a good fraction of the calibration lines. I'll leave them in like this overnight, and see if we get the expected improvement in the uncertainty (especially as reported by the front-end). 

Line              Freq     Former     New
PCALY             36.7      750       500
                  331.9     2900      5000
                  7.9       20000     5000

ETMY UIM          33.7      60        180
ETMY PUM          34.7      27        81

Note the reduction of the 7.9 and 36.7 Hz modes. We don't always increase line heights ;-).
Images attached to this report
H1 General
edmond.merilh@LIGO.ORG - posted 00:07, Wednesday 02 November 2016 (31105)
Shift Summary - Eve
TITLE: 11/02 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Lock Aquisition
INCOMING OPERATOR: Nutsinee
SHIFT SUMMARY:
LOG:

23:03 Fil out of LVEA WP6292

23:05 Dick G into CER

23:15 Dick back

23:34 Robert and Ansel out to EY, then EX

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