The original ETMY PUM coil driver (S1102652) was reinstalled this morning. Two hour lock shows little or no change in the glitch rate. The AI chassis controlling the PUM chassis was also power cycled.
This morning, Jason, Mark and I swapped the assumed-to-be failing TCSY flow sensor which has been showing epochs of glitching and low readout (while other indicators show normal flow, alogs 32712 and 32230). The process to do this was such:
1) Key laser off at control box in rack, LVEA
2) Turn RF off at mezzanine rack, Mech room
3) Turn chiller off on mezzanine, Mech room
4) Turn power off on back of controller box in rack, LVEA (we also pulled the power cable to the sensor off the front of the controller, but it was probably overkill)
5) Close in-line valves under BSC chamber near yellow sensor to-be-swapped, LVEA
6) Quick-disconnect water tubes at manifold near table, LVEA
7) Pulled yelow top off of yellow sensor housing under BSC at the piping, LVEA
8) Pulled the blue and black wires to the Power recepticles inside the housing (see pic attached). Pulled full grey cable out of housing.
9) While carefully supporting blue piping*, unscrewed large white nut holding housing/sensor to piping (was tough, in fact so tough that we later removed all of the teflon tape which was unneeded in his join)
10) Pull* straight up on the housing (hard) and it comes out of the piping.
11) Reverse all above steps to insert new housing/sensor, wires and turn everything back on. Watch for rolled o-rings on the housing and proper alignment of the noth feature when installing the new sensor. Verify mechanical flow sensors in piping line show ~3-4 G/m readout when flow/chiller is restored to functionality.
12) Setup new flow sensor head with Settings: Go to the other in-use sensor, pull off the top and scroll through the menu items (red and white buttons on the unit (shown in pic). Set the new head to these values.
13) Verify the new settings on the head are showing a ~3 G/m readout on the medm screen. If not, possibly there is setting on the sensor that needs revisited.
14) Monitor TCS to see that laser comes back up and stabilizes.
* Blue piping can crack so be careful to always support it and avoid torque torque
Note - with the sensor removed, we could see alot of green merk in the blue piping where the paddle wheel sits. Still suffering green sludge in this system...
A few pictures to add to those already posted. The O-ring closest to the paddle wheel had a cut to it. Not near the electronics, plus there's the other O-ring so it doesn't look like water was getting into where the electronics is housed. Some kind of stuff stuck to each blade (paddle?) of the paddle wheel. Not a good sign if the cooling water for the laser is meant to be clean.
Settings were as follows:
FLO Unit (Flow Unit) = G/m (default was L/m)
FActor (K-Factor) = 135.00 (default was 20)
AVErage (Average) = 0
SEnSit (Sensitivity) = 0
4 Set (4mA Set Point) = 0 G/m
20 Set (20mA Set Point = 10 G/m (default was 160)
ContrAST (Contrast) = 3
Here's both TCS system laser power and flow for the past day. The drop out in the ITMY data is our few hour sensor replacement work. So far no glitching or low droops. Although, there weren't any for the last 24 hours on the old sensor either.
Attached is a 14 day duration minute trend of the TCSy chiller flow rate and CO2 laser power since our swap of tthe TCSy flow sensor. There have been 7 glitches below 2 GPM, with 3 of those glitches being below 1 GPM; all 7 glitches occured in the last week. Unless the spare flow sensor is also faulty (not beyond belief, but still a hard one to swallow) the root cause of our TCSy flow glitches lies elsewhere.
It might be a good idea to try swapping the laser controller chassis next. The electronics path for this flow meter is very simple - just the controller and then into the EtherCAT chassis where it's read by an ADC.
This morning I re-centered the ITMx oplev. No issues were encoutered. This completes LHO WP 6406.
Did Zero Count and Flow tests on all dust monitors. Zero Counts were all OK. Flow is down a little (2.8l/m to 2.6l/m) on the dust monitor in the Biergarten and at End-Y. If flow drops any more will adjust during next months check. Made minor adjustments to the air bypass on all three vacuum pumps to bring the flow rate back to 19 inHg. All temperature check were within normal range. Closing FAMIS #7508
Carlos, Jim The raw minute trend writing has been restarted on h1tw0. Old raw trend files were removed.
A. Urban, on behalf of the calibration group
Around GPS second 1166295017 (2016 Dec 20 10:50 AM Pacific), I restarted the primary and redundant GDS calibration pipelines at Hanford. This restart picks up a software update to gstlal-calibration-1.1.3 (see https://alog.ligo-la.caltech.edu/aLOG/index.php?callRep=30528) which is not expected to have any effect on the output of the GDS online pipeline (it primarily affects the DCS pipeline in offline mode). The filters have also not changed from their previous configuration; see https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=32389.
In preparation for the holiday break, the timing setup in the EE lab was powered down. Since the timing signal comes from the master fanout in the MSR, timing overview MEDM screen showed an error, change in configuration. Error was cleared by Jim B.
J. Kissel Grabbed this week's charge measurements. The effective bias voltage (as gauged by the angular actuation strength) is still hovering around zero thanks to the idea Sheila implemented flipping the bias signs when the IFO isn't using the respective ESD; programmed into the ISC_LOCK guardian on ETMX on 2016 Nov 03 (see LHO aLOG 31172), and for ETMY on 2016 Nov 28 (see LHO aLOG 31929). I highly recommend LLO try out a similar scheme if and when they discharge their effective bias voltage back to zero. Also, re-reminding myself and/or anyone who has time: resurrect comparison between longitudinal actuation strength and angular actuation strength, a. la. LHO aLOG 24241.
Took a couple of thermal images of the pre-modecleaner body. The images are attached.
The shot of the ceiling was to get a reference for the room temperature.
Looks like the pre-modecleaner body is around 24.6 degC, except where the two Kapton
heaters are located and the piezo.
As per yesterday morning's meeting. The alignment to the reference cavity was touched up.
Mostly vertical adjustment, consistent with moving the beam up. I feel the alignment could
be a little better but stopped in the interest of time.
For reasons unknown to me, it seems that the alignment into the pre-modecleaner changed
whilst I was in the enclosure. At least the reflected spot camera image looked like it moved
to the left.
Evan G., Aaron V. I have checked a new filters file into the calibration SVN for offline (C01) calibration. The filters were made using revision #3987 using the script /ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O2/H1/Scripts/TDfilters/H1_run_td_filters_1165799036.m The file can be found here: /ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O2/GDSFilters/H1DCS_1165799036.npz In order to achieve agreement with GDS calibration, it was necessary to add a delay of 2 16kHz clock cycles to the actuation filters. Evan G. is reviewing the DARM model codes to determine where this timing discrepancy originated. The attached plots include: 1) h(t) spectrum from CALCS and DCS 2) ASD ratio (DCS / CALCS) 3 - 5) plots of filters and errors
These filters have been removed from the SVN. They were replaced by those discussed in https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=32965 For information on why this was necessary see https://alog.ligo-wa.caltech.edu/aLOG/index.php?callRep=32907
J. Kissel Title says it all. Will take about an hour while L1 is down.
Actuator measurements complete. Data committed and exported to: /ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O2/H1/Measurements/FullIFOActuatorTFs/2016-12-20/ 2016-12-20_H1SUSETMY_L1_iEXC2DARM.xml 2016-12-20_H1SUSETMY_L1_PCAL2DARM.xml 2016-12-20_H1SUSETMY_L2_iEXC2DARM.xml 2016-12-20_H1SUSETMY_L2_PCAL2DARM.xml 2016-12-20_H1SUSETMY_L3_iEXC2DARM.xml 2016-12-20_H1SUSETMY_L3_PCAL2DARM.xml Got half-way through the PCAL2DARM sweep for the sensing function then the IFO broke lock. Not the end of the world. Templates saved anyways, in case it does: /ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O2/H1/Measurements/SensingFunctionTFs/ 2016-12-20_H1DARM_OLGTF_4to1200Hz.xml 2016-12-20_H1_PCAL2DARMTF_4to1200Hz.xml Analysis to come, but preliminary results from the DTT templates themselves indicate that there has been very little change in the L2 stage response. *phew*! Since we were able to get these full IFO measurements out of the way, and it happens to be maintenance day, I still think it prudent for us to go down to EY an remeasure the poles and zeros of the new PUM coil driver box, however, unless we decide to revert the driver back. Evidence (i.e. the BNS range) from the ~2 hours of data before I got here seems to point to not too much of a change in glitch rate. Note, my estimate of "about an hour" was an *underestimate* if I were to have stuck with the plan of only measuring L2/PUM. However, because L1 called to say they're start maintenance early, I just went for the whole calibration suite shebang.
The OSB parking lot is slippery as a skating rink out there. Exercise caution.
10:44:24UTC
Attaching detchar tag.