Please look at the attached pdf file.
model restarts logged for Tue 07/Oct/2014
2014_10_07 08:44 h1iscey
2014_10_07 08:54 h1iscey
2014_10_07 09:07 h1iscey
2014_10_07 09:10 h1asc
2014_10_07 09:21 h1iscex
2014_10_07 09:35 h1asc
2014_10_07 09:35 h1iscex
2014_10_07 09:35 h1iscey
2014_10_07 11:05 h1calex
2014_10_07 11:05 h1iopiscex
2014_10_07 11:05 h1iscex
2014_10_07 11:05 h1odcx
2014_10_07 11:05 h1pemex
2014_10_07 11:59 h1broadcast0
2014_10_07 11:59 h1caley
2014_10_07 11:59 h1dc0
2014_10_07 11:59 h1fw0
2014_10_07 11:59 h1fw1
2014_10_07 11:59 h1iopiscey
2014_10_07 11:59 h1iscey
2014_10_07 11:59 h1nds0
2014_10_07 11:59 h1nds1
2014_10_07 11:59 h1odcy
2014_10_07 11:59 h1pemey
2014_10_07 12:39 h1iopiscey
2014_10_07 12:41 h1caley
2014_10_07 12:41 h1iscey
2014_10_07 12:41 h1odcy
2014_10_07 12:41 h1pemey
2014_10_07 12:45 h1iopiscex
2014_10_07 12:47 h1calex
2014_10_07 12:47 h1iscex
2014_10_07 12:47 h1odcx
2014_10_07 12:47 h1pemex
2014_10_07 12:48 h1broadcast0
2014_10_07 12:48 h1dc0
2014_10_07 12:48 h1fw0
2014_10_07 12:48 h1fw1
2014_10_07 12:48 h1nds0
2014_10_07 12:48 h1nds1
2014_10_07 13:04 h1pemex
2014_10_07 13:06 h1pemey
2014_10_07 13:08 h1dc0
2014_10_07 13:08 h1fw0
2014_10_07 13:08 h1fw1
2014_10_07 13:08 h1nds0
2014_10_07 13:08 h1nds1
2014_10_07 13:12 h1broadcast0
2014_10_07 14:56 h1calex
2014_10_07 14:56 h1iopiscex
2014_10_07 14:56 h1iscex
2014_10_07 14:56 h1odcx
2014_10_07 14:56 h1pemex
2014_10_07 15:02 h1iopsusex
2014_10_07 15:02 h1susetmx
2014_10_07 15:02 h1sustmsx
2014_10_07 15:06 h1hpietmx
2014_10_07 15:06 h1iopseiex
2014_10_07 15:06 h1isietmx
2014_10_07 15:35 h1calex
2014_10_07 15:35 h1iopiscex
2014_10_07 15:35 h1iscex
2014_10_07 15:35 h1odcx
2014_10_07 15:35 h1pemex
No unexpected restarts. A busy maintenance day. Daniel's ASC and ISC model changes. Addition of CAL models to end station ISC. Recovery of EX SEI and SUS after accidental crash. Associated DAQ restarts.
Sheila, Alexa, Kiwamu,
We noticed that occasionally the IMC locking loop kicks the FSS into a situation where the FSS oscillates for unknown reason.
We did not check what frequency the oscillation was, but this was visible in the PZT monitor in the FSS screen. It kept oscillating even after the IMC feedback onto FSS was disabled. We figured out that decreasing the common gain somehow fixes the oscillation. Strangely, once the oscillation was gone, we could set the common gain back to the nominal of 30 dB without the oscillation. We believe that this oscillation is a part of the reason why the IMC did not recover right away when it looses the lock.
For the commissioning tonight, we reduced the common gain to 18.8 dB.
Sheila, Kiwamu,
Our focus tonight were:
(DRMI 3fs are now stable)
We succeeded in transitioning to the 3f signals in DRMI. We checked the demodulation phase of REFLAIR_RF135 by exciting SRM and BS at a time. A good demod phase was found to be 56 deg while it had been -2.7 deg since the last week (see alog 14268). This demod phase was the one in which the SRCL signal is minimized in 135_Q. The resultant input elements are:
I have not measured the open loop transfer functions yet, but so far I did not see a gain peaking. The SRM M2 stage coil output had an rms counts of about 1x104 which is very OK in terms of the DAC saturation. I did not get a chance to see its long term stability. The ISC_DRMI guardian is edited accordingly and we confirmed that the guardian could transition to the 3fs automatically. Note that I enabled two whitening stages in REFLAIR_RF135. This saturates the ADC until the DRMI is locked, but once it is locked, the saturation does not seem to happen any more.
(some attempts on ASC loops)
For some reason, the SRCL mode-hop happened frequently tonight, even though the alignment was not too bad -- both PRC and SRC sideband power could fluctuate as small as a few % depending on misalignment which of course evolves on a time scale of order of 10 sec. So we decided to close the ASC loops rather than manually aligning the optics. We started from MICH which is ongoing.
Early in the evening last night we could not lock the input beam to the X arm (because of a maintence day snafu), and skipped this step of our inital alingment. Although the pointing down the arm seemed OK based on the flashes that we saw, it was actually not good. We then tried our inital alingment steps of PRX with refl wfs, which didn't work.
Once we had recovered the ETMX ISI we redid the intial alingment process from the begining, and it worked well resulting in a good alingment for DRMI locking.
There is a huge peak at 60 Hz in the damping singals on M0 of the SRM suspension. Also the noise floor seems too high compared with PRM. This must be fixed.
This has been this way for a long time....
Not that it should be prevent looking for and solving the problem, but this is most likely related to Integration Issue 935, see original discovery aLOG LHO aLOG 13556. Richard will be looking at it this morning, potential cutting ex-vacuo cabling to try to fix this known in-vac problem.
ETMX has tripped 4 times, and so has the BS. We have been actuating on ETMX, but don't think that is the proble. We definitely weren't actuating on the BS, there isn't anyone around in the LVEA. Most of the time the WD plotting script has failed, I did get a plot for the BS though.
ETMX tripped again, there was no isc feedback this time. It also tripped several more times while the guardian was trying to bring it back. We seem to be having an earthquake, but ETMX is the only chamber that isn't riding it out. Something must be wrong with this ISI.
The problem seems to have been that the configuration of the blends was wrong for both the beam splitter and ETMX. Jim confirmed that they are supposed to be the same configuration as the rest of the BSC ISIs, so I tried to match all the settings. It seems like the blend switching doesn't work with the new configuration,so while the ISis were tripped I went into the current blend filter banks individually and switched them all by hand. At least they are not tripping now.
How do these blends get switched into the wrong configurations in the first place? Does someone have a script that sets them corectly? Do we need to update safe.snaps?
The slow feedback from the green reflection PDH is working again, with the frequency servo on the end station VCOs. Hopefully this will make locking DIFF easier, since these should help to keep the DIFF PLL within its linear range, which it seems to be doing a reasonable job of right now.
Changes I've made are:
We need to revist the length to PIT for ETMX at verry low frequencies. This slow feedback is clearly misaligning the cavity.
Also late this afternoon early evening, ETMX ISI has tripped 3 times. The plotting script failed,
J. Kissel, K. Venkateswara
We installed and tested the damping turn-table for the BRS. While the basic scheme seemed to be working, we turned it off as we experienced some grounding issues which need to be sorted out.
The turn-table has two 1-kg masses located diametrically opposite. It's angular position between 0 and 90 degrees is controlled by a stepper motor/controller which is in turn controlled by an analog signal between 0-5V.
The control signal is currently being written out by the BRS DAQ program to the USB DAC card. The stepper controller is kept floating so that the control-signal ground defines the ground for it. This was apparently causing the controller to restart irregularly. So I tried grounding one end of the control-signal to the platform (which is grounded through the ion pump). This may have been slightly better but unfortunately there seemed to be a big voltage drop (~2 V) across the DAC card's ground and the platform ground which was corrupting the control signal. Better grounding of the platform and controller may help.
ITMY on the SITEMAP was pulling up ISI_CUST_CHAMBER_OVERVIEW_Z_to_RZ_Decoupling.adl rather than ISI_CUST_CHAMBER_OVERVIEW.adl (this is the misfortune alluded to previously.)
I corrected this on the SITEMAP--you'll need to get a new one.
Additionally, ArnaudP, our old friend, landed a nice chunk of guardian realestate on the overview, very nice, thank you AP!
And with my corrections noted in the previous log below, the IOP DACKILL notices are all useful now.
SITEMAP and the OVERVIEW medms are committed to svn.
Through a series of unfortunate incidents, I ended up copying an older BSC-ISI Overview onto the current and lost changes made to naming of IOP_DACKILL channels.
However, following the guidence in the subject alog resulted in incorrect channel names. The corrections to this guidence are:
$(IFO):IOP-SEI_$(IOP)_SEI$(CHAMBER)_DACKILL_STATE, with $(CHAMBER) taking the following values: 'BS', 'ITMX', 'ITMY', 'ETMX', 'ETMY'
This is not correct, it should be:
$(IFO):IOP-SEI_$(CHAMBER)_DACKILL_STATE, with $(CHAMBER) taking the following values: 'BS', 'ITMX', 'ITMY', 'ETMX', 'ETMY'
This line too in the medms needed to be corrected from $(IFO):IOP-$(IOP_NAME)_DACKILL_STATE to $(IFO):IOP-SEI_$(CHAMBER)_DACKILL_STATE
I have added this correctioin to 12441.
Cyrus, Jim, Rick, Shivaraj, Dave
WP4888
Two new H1 front end models were created, h1calex and h1caley. They run on the end station ISC front ends, using the 4th user-model core. We assigned them the next two spare DCU-IDs (h1calex=124, h1caley=125).
The cal models currently only have the PCAL subsystems. I took the latest version of the PCALX code from h1odcx (where it was temporarily installed for testing) and installed on both end stations. The models' channels have the prefix H1:CAL-PCAL[X,Y]_. The CAL models are located under SVN in the ISC path (isc/h1/models/h1cale[xy])
The CAL models use the first ADC because they require the DUOTONE timing signals. The PEM models were modified to use the 4th ADC. The ISC models continue to use the 2nd and 3rd ADC and did not need modification.
The CAL models use the newly installed 18bit DAC card. This card is also used by the PEM model to drive unused channels (I modifed PEM accordingly).
The DAQ master and H1EDCU_DAQ.ini files were modified to include the new CAL models.
The IOP models h1iopisce[xy] were modifed to add the 4th ADC and 18bit DAC.
All models on the ISC front ends and the DAQ were restarted several times during this install.
Here is a summary list of model changes
| h1iopiscex | add ADC and 18bit DAC |
| h1iopiscey | add ADC and 18bit DAC |
| h1pemex | switch ADC from 1st to 4th and add 18bit DAC, filter modules to drive unused DAC channels |
| h1pemey | switch ADC from 1st to 4th and add 18bit DAC, filter modules to drive unused DAC channels |
| h1odcx | remove PCALX part from this model |
| h1calex | New CAL EX model. Uses 1st ADC and 18bit DAC (first channel) |
| h1caley | New CAL EY model. Uses 1st ADC and 18bit DAC (first channel) |
The CDS overview MEDM screens (large and small) were modified to include the new end station CAL models. Also the h1oaf0 was modified to put in place holders for the GAMMACAL and CALCS models which will be installed soon.
PeterK and RickS - FSS AOM replaced. Heat sink, aluminum baseplate, kapton insulators, nylon screws added. (see photo below) - Measured RF power at input to AOM: 22.5 Vp-p -> 7.96 Vrms -> 1.27 W. About right. - Aligned AOM. Power just upstream of AOM: 68 mW; Power just downstream: 58 mW. 85% efficiency. Very good. - Second pass, measured just upstream of EOM: 47 mW; 81% efficiency. Good. Double-pass efficiency 69%. Good. - Power downstream of EOM, downstream of RC modematching lens L12: 47 mW. Good. - M27, first turning mirror downstream of EOM was not locked, now is. - Aligned into reference cavity using two periscope mirrors. Max Tx PD DC out: 2.37 V. Locked both periscope mirror mounts. TxPD DCout after locking mounts: 2.35 V. - Centered beam on RFPD. Locked all three actuators on first steering mirror upstream of RFPD. - FSS RFPD unlocked: 360 mW; locked: 37 mV -> 90% visibility. Not too bad. - TTFSS gains (FAST/Common): 15/30 dB; measured UGF 340 kHz; phase margin > 50 deg. Notch at 770 kHz. Peaks at 1.77, 1.93, and 2.48 MHz up to within 2-3 dB of unity gain (see photo below). Probably should be addressed by rolling the loop off more aggressively above 1 MHz, or so. - Frontend watchdog disabled at start of work, enabled at close of work. Overall, loop seems to be functioning well.
Isomet AOM 1205C-843 S/N 120684, purchased under P/O S127984. Replaces the AOM purchased during the Initial LIGO era.
Plot of the reference cavity transmission and pre-modecleaner output after the work on the AOM. There are two discontinuities in the reference cavity transmission. The first probably coincides with the FSS oscillations noted by Kiwamu earlier today. The second change might be due to the common gain being reduced to 18.8 from 30.0.
I have had a difficulty transitioning the SRCL signal from the 1f to 3f signal. Not solved yet.
After playing with ALS DIFF, I went through the initial alignment process and then moved onto the DRMI. As tested before (alog 14283), the 1f locking with REFLAIR was fine with a laser power of 10 W incident on IMC. However I kept failing in the transition from the 1f to 3f signals tonight. It was due to the SRCL loop which did not like the 3f signal tonight for unknown reason. The PRCL and MICH loops could be transitioned to RF27_I and RF135_Q respectively without a problem. But SRCL seemed to saturate the M2 stage DAC every time (??) when I tried to engaged RF135_I. I tried adjusting the demod phase, but did not seem to help. Also checked the optical gain by exciting SRCL and confirmed that the input element of -2 which was taken care by the guardian is right. Also tried it with two whitening stages on in REFL135, but this did not help either.
Note that the build up of the sideband power looked high tonight:
Also, I had the modified L2P decoupling filter engaged on the M2 stage of SRM (see alog 14304) all the time tonight.
Here is a lockloss science. Not clear what exactly was going on.
I looked at three different lock loss events from yesterday. All of them were associated with very large saturation in the M2 stage of SRM which seemed to trigger instability in SRCL and destroy all the LSC loops eventually within a 2 sec or so.
The attached plot is the one from Oct-07-2014 09:24:22 UTC. In this example, PRCL and MICH had been already controlled by the 3f signals (i.e. RF27_I and RF135_Q respectively). In the middle of the plot, the SRCL 3f signal was ramped up (though it actually ramps down because of the control sign. The 1f signal was ramping down at the same time which is not shown in the plot.) Apparently the SRM M2 stage saturated quite hard. Following the M2 stage, the SRM M3 stage hit the DAC range as well. The BS and PRM M2 stages did not saturate until the loops became completely broken. An oscillatory behavior was seen in all three length signals and it was roughly at 13 Hz. Hmmm...
J. Kissel Following a similar procedure as was done for the ITMs (see LHO aLOG 14265), I've refined the calibration for the H1 SUS BS optical lever. The new calibrations are BS P 6.9522 [ct/urad] BS Y 3.8899 [ct/urad] They've not yet been installed; will install tomorrow during maintenance. DETAILS ------------ Currently, the alignment slider calibration gains are 4.714 [ct/"urad"] 4.268 [ct/"urad"] based on dead-reckoned knowledge of the actuation chain (see LLO aLOG 5362). Sheila and Alexa recently found the alignment values for the beam splitter which gets red light onto the ETMY baffle PDs: P ["urad"] Y ["urad"] ETMY PD1 184.0 -255.0 ETMY PD4 237.1 -287.7 or a displacement of BS P 53.12 * 2 = 106.2 ["urad"] BS Y 23.70 * 2 = 65.4 ["urad"] where the factor of two comes from the single bounce optical lever effect. I spoke with Gerardo who informed me that the numbers Keita had posted (LHO aLOG 9087) for the locations of the baffle PDs on the Arm Cavity Baffles are slightly off from reality. He gave me links to D1200296 (ETM) and D1200313 (ITM), which indicate that the PD locations are identical between an ITM and ETM baffle, and are 11.329 [inches] = 0.288 [m] apart in vertical, and 11.313 [inches] = 0.287 [m] apart in horizontal. Again using 3994.5 [m] for the length of the arm (LHO aLOG 11611), and adding 4.847+0.100+0.020+0.200 = 5.167 [m] for the distance between the HR surface of the BS and the back of the CP, through the thin CP, through the ITM QUAD's reaction-to-main chain gap, and through to the HR surface of ITM, respectively (D0901920), that's a lever arm of 3999.7 [m]. Hence, a displacement of BS P 0.288 [m] / 3999.7 [m] = 72.01 [urad] BS Y 0.287 [m] / 3999.7 [m] = 71.76 [urad] The alignment offset slider gains should therefore be corrected by BS P 72.01 / 106.2 = 0.67806 [urad/"urad"] BS Y 71.76 / 65.4 = 1.0972 [urad/"urad"] or BS P 1.4748 ["urad"/urad] BS Y 0.91141 ["urad"/urad] The new slider gains should therefore be BS P 4.714 [ct/"urad"] * 1.4748 ["urad"/urad] = 6.9522 [ct/urad] BS Y 4.268 [ct/"urad"] * 0.9114 ["urad"/urad] = 3.8899 [ct/urad] We're now storing 4 alignments for the BS, P ["urad"] Y ["urad"] BS Aligned 210.6 -271.4 Misaligned 236.5 -287 To EY ACB PD1 184 -255 To EY ACB PD4 237.1 -287.7 which should therefore become, P [urad] Y [urad] BS Aligned 142.8 -297.3 Misaligned 160.3 -314.9 To EY ACB PD1 124.76 160.77 To EY ACB PD2 160.7 315.66 To do: - Update calibration in OPTICALIGN gain - Update calibration in M1 LOCK bank - Update, confirm, and save corrected alignments - Capture new safe.snap
OPTICALIGN Calibration gains have been changed, but only the ALIGNED and MISALIGNED values have been stored. Still need store PD1 and PD4 values, commit the snaps to the userapps repo, and capture a new safe.snap. Turns out there are NO calibration filters in the H1SUSBS M1 or M2 LOCK filter banks yet, so they need not get updated. Will do what I can tomorrow.
Completed OPTICALIGN alignment offset slider calibration refinement this morning: saved ALIGNED_TO_PD1 and ALIGNED_TO_PD4 values, confirming that they're hitting the ITMY baffle PDs. Finally, captured a new safe.snap. Now moving on to optical lever calibration refinement using new values.
SEI MEDM screens were all updated (HAM-ISI, BSC-ISI, HEPI) to account for the recent changes in the IOP Dackill channels names.
Displays are fully functional again for both HAM-ISI and HAM-HEPI. (before/after - notes)
BSC-ISI and BSC-HEPI need the IOP DACKILL parts to be updated so channel names match with chamber names, as It is currently the case on HAM chambers. DaveB has agreed to do those changes, and the related model restarts, next week so the BSC chamber IOP DACKILL channels are named as follow:
$(IFO):IOP-SEI_$(IOP)_SEI$(CHAMBER)_DACKILL_STATE, with $(CHAMBER) taking the following values: 'BS', 'ITMX', 'ITMY', 'ETMX', 'ETMY'
Work was performed under DaveB's WP #4672
$(IFO):IOP-SEI_$(IOP)_SEI$(CHAMBER)_DACKILL_STATE, with $(CHAMBER) taking the following values: 'BS', 'ITMX', 'ITMY', 'ETMX', 'ETMY'
This is not correct, it should be:
$(IFO):IOP-SEI_$(CHAMBER)_DACKILL_STATE, with $(CHAMBER) taking the following values: 'BS', 'ITMX', 'ITMY', 'ETMX', 'ETMY'
This line too in the medms needed to be correct from $(IFO):IOP-$(IOP_NAME)_DACKILL_STATE to $(IFO):IOP-SEI_$(CHAMBER)_DACKILL_STATE
