J. Kissel for S. Ballmer Stefan noticed that the H1 SUS ETMY UIM (L1) UR and LL Coil Driver Current Monitors (specifically the FAST_IMON) H1:SUS-ETMY_L1_FASTIMON_LL_MON H1:SUS-ETMY_L1_FASTIMON_UR_MON are unresponsive to a DC offset. We should fix this.
I don't understand this at all, but I noticed that changing the polarity of the bias for DC channel as well as the offset of each quadrants changes the response of ESD measured by OPLEV.
I first set DC bias to 125000 counts, set the offsets of all quadrants to 51776, injected into each quadrants, one by one at 3.2Hz, and measured the transfer coefficients from the excitation to the OPLEV. No filter in the injection path, so this is the TF from ESD digital output to the oplev. Injection amplitude is either 40000 or 20000 counts.
Then I flipped the DC bias and offsets, but without flipping the signal polarity, and repeated the measurements at 3.19 Hz. The TF polarity flipped as expected, but the TF amplitude increased overall by a factor of 1.2-ish if you look at PIT, or 1.6-ish if you look at YAW.
In the attached, left two panels show PIT response, right YAW. In in each panel, to the right is non-flipped data set, to the left is flipped.
This is highly repeatable, the measurement error seems to be 5% or less. The results don't depend on the excitation amplitude (this is expected).
From the fact that the TF polarity flipped though the excitation polarity stayed the same, this cannot be just electronics coupling into OPLEV.
Keita, Do you suppose it is simply that the force is proportional to (Vsig-Vbias)^2 ? RW
My point is that it should be proportional to (vsig-vbias)^2, but it doesn't appear to be.
Expected behavior is that when you flip the sign of vbias without flipping vsig, you will have exactly the same amplitude (which is not the case in my measurement) but with exactly the opposite polarity (which is the case in my measurement).
Since I'm not measuring vbias (I just trust the DAC counts), it could be that there's an offset in ESD driver, but the offset should be huge.
Charge?
DaveB, JimB, CoreyG, RickS We recently discovered that the PDA DC and PDB DC readouts on the MEDM screens were about a factor of ten lower than they had been. After some investigation today, we found that the gains in the filter modules had been changed from -1 to -.116 and -.108 respectively on March 18th. The safe.snap file has the -1 values. Not knowing why or how they changed, we changed them back and the MEDM screen now has the normal appearance, with the "DC" signals about 5 times the "AC" values. The voltages measured on the inputs to the ISS Servo module in the LVEA, from which the "AC" and "DC" output signals are derived, are about 1.7 V, same as the "AC" values on the MEDM screen. The servo seems to be functioning normally. Note for operators: The ISS varies the amount of light diffracted out of the PSL beam such that the "AC" output of the selected photodetector matches the "requested" REFSIGNAL value. Thus in the attached photo, the PD A Output AC value of 1.67V equals the requested -1.67 V (opposite sign). Photos attached: Left side of PSL ISS screen. Filter module before making the changes today. Filter modules after making the changes today. Matlab script for the "Cali-mean" F1 filter. Note the gain of -4.91999.
Comparing to Den's LLO alog 12590, we have about 10 times more DIFF noise at 10Hz, PLL locked, DIFF not locked. This turns out to be crucial for actuation range. So we looked at our DIFF noise using a simulated beat note, generated using an FM modulated RF source. The first two traces of the attached plot show the noise using a fixed-frequency (unmodulated) RF source. The first (red) uses the additional /10 frequency difference divider (FDD), the blue doesn't. note that the blue trace is pretty close to the noise seen at LLO. Traces 3 and 4 show the noise using an additional 0.3Hz, ~45kHz amplitude FM modulation, again with and without FDD. While the signal seems suggestively close the our in-lock signal (black), the interpretation is not straight forward. - We noticed that the hight frequency increase was at least part to an imperfect digital modulation drive of the RF source. switching the RF source to an IFR affected the noise level at high frequency. - Up to about 10Hz this seems to be an (unresolved) harmonic forest from up-conversion. Unfortunately I can't say for sure from which source - the IFR actually gave me worse noise at low frequencies.
David H and Greg G - CO2 laser on the TSCX table had run overnight, no issues with temperatures or output power. Was turned off at 1015 local time for some testing by Aidan, as he was looking at the dark noise of the ISS PDs. - Corner Hartmann table optics continued to be mounted and positioned. Minor adjustments made to the position of some on-table cables. - TCSY laser table work: continuation of alignment attempted but due to some irregularities in the positions of the first few optics (beam splitter, polarizers), with regards the relative positions of the laser and periscope, the co-ordinates of the table holes were relabeled and the table layout will likely need to be adjusted slightly. TSCX laser was turned on again at ~1715local and will run overnight. Table doors are locked. TSCY chiller and power supplies have been left running, TCSY laser is turned off.
- TCS to HWS table in LVEA - Corey to MY - Jason to HAM5 for alignment work - Jeff to HAM5 - Praxair on site - Paradise Water on site - CDS for external users going down, J. Hanks - DAQ reboots for SUS model changes - Rick going out to PSL area to look at ISS
I moved the tune offset on the IMC VCO, and HAM2 HEPI tripped, (plot attached) HAM2 ISI, HAM3 IOP tripped so HEPI, ISI MC2, and PR2 were all tripped.
While we were trying to recover things tripped again.
One way that works to recover from this is to:
After all the model changes I reconfigured the conlog channel list. It added 205 channels and removed 104 channels.
The unmonitored number went to zero , but I noticed the queue size was at 9e06. Trending shows that the queue increased linearly from zero to 1.8e7 from noon to 15:30 PDT this afternoon, then has been decreasing linearly with the same slope since then. I caught it at 9e06, it is now 6.7e6. Presumably at 19:00 it will be back to zero.
Following are the final alignment numbers for SR3.
Tomorrow morning I will begin setup for the X, Y, Z alignment of SRM so the alignment equipment is ready once SRM is installed.
As discussed last week during the SEI call, we are going to try to subtract the unwanted coupling from Z drive to RZ T240 Signal.
While we are still investigating the cause of this coupling (magnetic coupling test in the Staging building, Stage deformation FEA at MIT...), online subtraction is for now our only option to move forward.
This test can't be performed at the univeristies (Stanford and MIT protoypes use STS2's and the Stage 1 structures are different) so we have to try it at the sites.
Work permit #4626 has been filled and approved.
I am going to start modifying the Two stage Master simulink. We'll coordinate with install and commissioning activities as for when and which unit to use to test this modification.
Depending on results, we'll decide whether to revert or propogate this feature.
Spent some time driving each segment of the ESD individually with UL being week and UR, LR not Really being seen. LL and DC making the most movement as seen on the oplev. Trying to make some sense out of the unit put offsets on various combinations of ESD segments trying to get a decent yaw or pitch movement. This would help with the swapped cable theory. I would apply a 125K offset to two segment then make the offset -125k. Again not much luck. Attached are a couple of the plots first being individual drives. Second LL and DC together then sign flip. Ran every combination of paring this is just representative of responses. With UR,LR the response was not as dramatic.
Richard you might set up the bridge capacitance circuit and note the change in capacitance as you drive the PUM mass magnetically at the pendulation frequency. It will help in determining if you have open or shorted connections and, from the spectrum, if the mirror is touching something.
ETMY ISI tripped again, possibly when I isolated HEPI after already isolating the ISI. The blends were also set incorrectly. (all Tbetter) We have been using Tcrayy for RZ on stage 1 and 2, and I think that we are still using Tcrappy for stage 2 RX (I wrote that Tbetter was wrong in alog 11563, and I'm not aware if anyone has fixed it.)
I also noticed that it is possible for the TMS guardian to say that TMS is alinged, even when the master switch is off.
I also burted asc and lsc to mid night last night.
I also moved IMTY blends from T750 back to Tcrappy, and turned on sensor correction
Tuesday 13th May 2014 Maintenance Summary
RFM DMA setting [WP 4625]
I modified all models running on h1susex, h1seiex, h1susey and h1seiey to add the "rfm_dma=1" setting in their CDS block. The models on these front ends were restarted following the procedure:
stop user models, restart IOP model, start user models
Initial results suggest the ISC to LSC IPC error rate is slightly worse if anything.
I had some problems modifying the h1isietmx.mdl file. It was locally modified and also modified in the repository. The local changes appear to be purely because the model was saved using matlab2011a (presumably during the network outage). I resaved the local version with matlab2012b. Then I checked out the repo version in my home directory and diff'ed the two files. They did not differ by any significant factors. So I reverted the h1 model, applied the dma changes and compiled.
DAQ Reconfigure
The DAQ was reconfigured due to:
The DAQ was restarted at 11:49 and 14:06PDT to support these changes.
h1asc
Some time ago I worked on the compile error of h1asc to add ADS components. At the time I had performed a "make install-h1asc" but we were not ready to start the new model.
today after the first DAQ restart h1asc went into 0x2000 DAQ status due to the modified INI file. I was able at 14:09PDT to restart the new h1asc model to return the DAQ synchronization.
The new model has receivers for the new ALS_ASC_LOCKIN_OSC_CLK RFM IPC parts (two per end station for OSC1 and OSC2). Of the four new IPC channels only one is working. The other three are maxed out on their receive errors (2048 per second). Investigation is continuing.
OS patching
I performed the usual set of OS patches on vulnerable machines. No reboots were necessary to apply the patches.
Restart Reports Covering This Work
All times local PDT.
2014_05_13 10:48 h1hpietmx
2014_05_13 10:48 h1iopseiex
2014_05_13 10:50 h1isietmx
2014_05_13 10:51 h1iopsusex
2014_05_13 10:53 h1susetmx
2014_05_13 10:53 h1sustmsx
2014_05_13 11:21 h1susetmx
2014_05_13 11:24 h1susetmx
2014_05_13 11:49 h1broadcast0
2014_05_13 11:49 h1dc0
2014_05_13 11:49 h1fw0
2014_05_13 11:49 h1fw1
2014_05_13 11:49 h1nds0
2014_05_13 11:49 h1nds1
2014_05_13 13:41 h1susetmx
2014_05_13 13:51 h1susetmy
2014_05_13 13:52 h1susetmy
2014_05_13 13:57 h1iopsusey
2014_05_13 13:59 h1iopseiey
2014_05_13 13:59 h1susetmy
2014_05_13 13:59 h1sustmsy
2014_05_13 14:01 h1hpietmy
2014_05_13 14:01 h1isietmy
2014_05_13 14:06 h1broadcast0
2014_05_13 14:06 h1dc0
2014_05_13 14:06 h1fw0
2014_05_13 14:06 h1fw1
2014_05_13 14:06 h1nds0
2014_05_13 14:06 h1nds1
2014_05_13 14:09 h1asc
Today, I removed the FirstContact sheet from the SR3-AR surface. Then, Jason and I aligned the SR3 in yaw and pitch. After resetting the top stage BOSEMs, we confirmed with quick TFs in V, L, and P that the suspension is hanging free. The lower stage OSEMs are not in place yet. Jason will post final pointing numbers. We are good to move on to the SRM installation and subsequent alignment in HAM5. We should start that install tomorrow.
ETMX was probably due to sus modle restart, ITMY I'm not sure, ETMY guardian was red because it could not connect to a WD channel
Jim, Fabrice:
To help understanding the Z to RZ coupling, we have setup a test in the staging building in which we drive an actuator not attached to the structure. The actuator is seating on the top of Stage 1 (a few inches above where it is normally installed). No brackets connected, indeed, so the actuator can't drive any motion.
We do see some direct pickup, as shown in th attached plot. The coherence is, however, stronger in the vertical directions, unlike the coupling we are chasing in the units installed in the chambers.
Added a ZFL-500HLN amplifier to the ALS DIFF RF path.
Alexa and I found that this amplifier was not working, so we removed it.
The amplifier on DIFF was not working because we had input/output backwards. I have installed another amplifier on DIFF. I have also put a new amplifier on COMM (HNL) that piggy-backs the power from the BBPD; this amplifier has slightly less gain (about +24dBm in comparison to +30dBm), so we expect about -7dBm for the beatnote.
After Sheila saw some excess angular motion caused by the length drive, I tried improving the decoupling of EX and EY UIM.
[Keita Arnaud]
Measurements live in /ligo/svncommon/SusSVN/sus/trunk/QUAD/H1/ETMX/SAGL1/Data called 2014-05-13_H1SUSETMX_L1_{L/P}2PY.xml
For info : the only test that have been carried out yet (with Phil) to understand those non responsive channels was to measure the voltage between the monitor output and the anti aliasing chassis. For the 4 channels we saw a similar voltage readback increase when sending thousands counts, meaning the problem could come from anywhere from anti alias to model wiring. More details on the pb : here