chandra.romel@LIGO.ORG - posted 15:41, Thursday 08 June 2017 (36738)
Replaced IP9 power supply
Earlier this morning after the VEAs were swept, we had to go through a couple of other items before we could get back to OBSERVING:
1) DIAG_EXC
We had a stuck ASC Excitation channel (H1:ASC-INP1_P_EXC). Dave confirmed this excitation was run briefly (seconds/minutes?) on Maintenance Day and has remained OFF ever since. So Dave cleared this excitation test point and h1asc is no longer red on the CDS Overview.
2) DIAG_SDF (see attached screenshot of all diffs found this morning before they were addressed.)
We had handful of SDF Diffs in a few systems, but surprisingly not a whole lof of diffs.
Went over Past Tues Maintenance Open items
New Items for June 13th Maintenance (there was mention of possibly going over 4hrs)
Closed meeting by going over work permits on the TV.
Vacuum staff is aware that annulus IP on HAM 11 is out of range again. Next Tuesday we will check it out. It failed recently but Kyle revived it with a tap. We may have a leak in the o-rings.
CP4 log file DOES NOT exist!
After getting Official OK from the LHO Run Coordinator (Keita Kawabe), and help with others to address a few tasks Keita wanted addressed, as of June 8th 18:40:06 UTC, H1 is now back to OBSERVING (H1 had been out of OBSERVING for a month & have now rejoined L1 in O2!).
LHO Operator Team: Ops Observatory Mode Returns
This had been in PLANNED ENGINEERING for most of the last month. Let's return to the habit of marking H1's Observatory Mode.
H1:SUS-ITMY_R0_OPTICALIGN_P_OFFSET (from -150 to -400), this is for HWS and ghost beam (alog 36264).
H1:LSC-PD_DOF_MTRX_SETTING_4_1 and 4_7 (from [0.0091, -849] to [0.035, 0]). These are for PRC input matrix (alog 36473).
H1:ALS-C_COMM_A_DEMOD_LONOM (from 19 to 12). Don't know why it was 19dBm, 12dBm sounds good to me.
H1:ALS-X_LASER_HEAD_NOISEEATERTOLERANCE (from 0.5 to 0.6), H1:ALS-X_REFL_SERVO_COMOFS (from 0.375 to 0.25). These were all changed during the X end investigation.
H1:ALS-Y_REFL_A_DEMOD_LONOM (from 20 to -100) and B_DEMOD_LONOM (from -100 to -9), we used to use channel A but at some point A was broken and we switched to B. Since then the board was swapped and both work but we still use channel B.
H1:ALS-Y_VCO_REFERENCENOM (from 21 to 20).
H1:ALS-X_QPD_A_YAW_OFFSET, H1:ASC-X_TR_A_PIT_OFFSET, H1:ALS-Y_QPD_A_PIT_OFFSET, H1:ALS-Y_QPD_A_YAW_OFFSET, H1:ASC-Y_TR_B_PIT_OFFSET and H1:ASC-Y_TR_B_YAW_OFFSET, no real change, just the numerical error on the order of 1E-17.
H1:ASL-X_FIBR_LOCK_TEMPERATURECONTROLS_HIGH and LOW were temporarily set to +-1300 during the X end investigation, doesn't look like we need to keep it, reverted them back to +-600.
H1:ALS-Y_REFL_SERVO_IN2GAIN was set to 1, don't know why but inconsequential, reverted to 0.
Measured the tuning coefficient of the laser crystal temperature for Prometheus S/N 2011B
(the one that was removed from EndX a week or so ago).
The tuning coefficient is ~2.72 GHz/V for the green light and is fairly constant for
laser crystal temperatures from 24 degC to 34 degC.
Increasing the laser crystal temperature decreases the laser frequency. Increasing the
diode current also decreases the laser frequency.
On the Ops white board, there is a note of the last time the VEAs being swept on May 2nd.
Jeff mentioned needing to unplug unneeded items at the End Stations, and I unplugged unused extension cords & phones. For the H1 PSL, I went through the checklist to confirm the room is in "Science Mode". I assume we do not do this for H2 PSL because it running at 100%.
The primary and redundant DMT processes at LHO were restarted at 1180972740. It appears there was a raw data dropout starting at 2017-06-08 8:36 UTC that lasted almost 7 hours. After this, the calibration pipeline was running but producing no output. A simple restart seems to have gotten data flowing again.
This restart also picked up the new version of the calibration code, gstlal-calibration-1.1.7. This was automatically (unintentionally) installed during Tuesday maintenance.
After noticing that our range plot on the wall was down this morning, it appears it is now back (posting time is now current & we can see that there is roughly 6-7hrs of no H1 data on this plot). H1 range is currently being listed as ~64.7Mpc.
TITLE: 06/08 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: Patrick
CURRENT ENVIRONMENT:
Wind: 14mph Gusts, 9mph 5min avg
Primary useism: 0.02 μm/s
Secondary useism: 0.13 μm/s
QUICK SUMMARY:
We currently do not have the GWI.stat or our DMT view showing the H1/L1 BNS ranges (Cheryl has emailed local CDS staff); we can see that we've been at NOMINAL LOW NOISE for just under 6hrs. Don't have a range to report, but the DARM spectrum on the front wall looks close to the reference.
At some point this morning we would like to do Sweeps of the LVEA & End Stations
I was not the outgoing operator.
Kyle, Gerardo, Chandra, John
CP4 liquid level control appears to be controlling normally now. The large dip in the red trace is likely due to warm gas in the liquid transfer line being pushed into the pump as the transfer line cools to liquid temperature. This means that the 20% setting was not enough to keep the transfer line cold.
Blue is the control valve position.
The current setpoint is 96%.
It would be nice if DVWEB could provide up-to-the minute data.
Here is the MY chamber pressure for the last 28 hours as well as the liquid level for the same period. Pressure spike at 5 hours was due to the loss of the ion pump.
The large drops in liquid level are not real - they are due to human actions. The smaller drops to the 80 and 90% range are real and normal as the PID control takes over from manual settings.
Amazing!
This is the result of applying GN2 pressure (40-100 psi) to the clogged sensing line for many days (vs hours that we had tried in the past). We think we melted the blockage with the relatively warm gas. Went through two bottles of GN2 with a few small leaks in fittings.
Happy to close out FRS 6875!
I lowered the %full set point to 92% and LLCV lower limit to 30% open since we think 20% warms the transfer line.
The following pressures were recorded for the following Dewars:
8514371 = 50 microns 8514372 = 25 microns 8514374 = 225 microns <-- also knows as CP3. 8514375 = 19 microns 8514376 = 25 microns 8514377 = 30 microns 8514379 = 26 microns 8514380 = 27 microns
1 micron of Hg = 0.001 Torr
225 micron = 0.2 Torr