J. Kissel, K. Kawabe, T. Shaffer, C. Gray

After a message popped up on the ISC_LOCK guardian to review the last check of the AS port fast shutter, and we realize the last check should have been during the power glitch recovery, we manually checked the functionality of the fast shutter. The fast shutter appears functional, stopping light into the OMC breadboard and the GS13s show an impulse.

The manual check: 
Setup:
- The IMC is locked, and the IFO aligned enough to see flashes on the AS port camera
- Watching the OMC Breadboard QPDs MEDM screen to see a spot moving around (channels H1:ASC-OMC_A_[YAW,PIT]_OUTMON)
- Watching the HAM6 GS13s on a dataviewer session to watch for fast physical motion of the shutter (channels H1:ISI-HAM6_BLND_[X,Y,Z]_GS13_CUR_IN1_DQ)

The test:
- Use the fast shutter detail MEDM screen (sitemap > LSC > shutters > bottom middle "Detail" under the "HAM6 Fast Shutter" name)
- Hit "open" then "close" several times, watch for light to disappear from the OMC Breadboad QPDs, and watch for large impulse on GS13s.

We need to do a similar test after every power outage, no matter how small.
TJ has agreed to create a guardian "PRECHECK" state such that we can do manual check of the fast shutter functionality. (To date we've only done the automatic checks every 48 hours).
Note: There already exists a guardian check in the FAST_SHUTTER node, however, the check is programmed to fail without the IFO MUCH further into the lock acquisition sequence (i.e. DRMI locked), and we'd prefer to check the functionality far before this.

Post power glitch, ETMY ring heater was on with 0.55 W top and bottom. DIAG_MAIN reported that this is nominally OFF, and trends for the past few days agreed. I brought these back to 0 and double checked the others as well.

The ITM ring heaters were not checked in DIAG_MAIN so I added them. As of right now it will check if they are off or on (not for specific values), if only one half is on, and if the top and bottom differ by some threshold percentage. I'd like to add checks to make sure that they are at their correct values as well, once that seems to be in a stable state.

X wrong polarization % before = 15

Y wrong polarization % before = 6 (then 13 after turning the box on)

-----

X wrong polarization % after = 5

Y wrong polarization % after = 3

10am local

Took 14:30 min to overfill CP3 with 1/2 turn on bypass LLCV. Increased manual setting to 19% (from 18%).

Left exhaust bypass valve open.

J. Kissel, B. Weaver, C. Vorvick, C. Gray

After front-ends were recovered (LHO aLOG 30088) from last night's power glitch (LHO aLOG 30083), we slowly have gone through all SEI and SUS untripped watchdogs, recovered full isolation, restored damping and alignment. All systems appear free of damage. It is likely, however, that bounce, roll, and voilin modes of the QUADs will be rung up, so we'll be mindful of them as recovery continues.

We've also confirmed that ESDs are functional, and all bias signs are where they're supposed to be as of the most recent sign flip (LHO aLOG 29397).

This morning around 8:30am, Nutsinee and I went out and restarted the TCS chillers and the TCS lasers.  We also took the opportunity to swap the greenish filters.  Recall, we had flushed both chillers last week, but when we installed a new set of filters we noticed that they were tinging green immediately even though we had just flushed the system.  These filters sat for ~a week and we swapped them today in hopes that whatever immediately turned them green last week was just still pushing throgh the system.  We also had to add another 750mL (to top off the half way full indicator to full) and again inspected for leaking water (none found).

We'll need to look up how to clean these recyclable filters.

Found that the dewpoint monitor IOC had frozen, the values on the MEDM screen were white.  Killed the processes and restarted the IOC.  Since these values don't change much normally, it's difficult to tell when it stopped running.  A trend for the last 10 days shows no variation.

Richard restarted all the front end computers after the power glitch.  The push button switch on h1susb123 stuck in, preventing the computer from starting.  Once that was discovered, the models on the Dolphin network should have started but didn't.  Suspecting another computer was down, I started the dxadmin tool on the h1boot server, and found that the dolphin node manager wasn't running.  After starting that, the models started coming to life.  Models on three computers didn't start, h1susey, h1sush56, h1sush2b, so those were killed and started manually.  IRIG-B timing on the h1ioppsl0 model went negative, but recovered within 30 minutes. IRIG-B timing on h1iopasc0 and h1iopsush56 drifted positive, and are working down toward a normal value.

This morning, after the power glitch, I went out to check the settings for the analog communication voltage scaling for the TCS chillers.

For both TCSX and TCSY chillers:
High Volts: 10.0
Low Volts: 0.0
High Temp: 40.0
Low Temp: 5.0

These are the same as the defaults listed on page D-5 of the Thermo Scientfific ThermoFlex Recirculating Chillers (Deluxe Controller) manual (P/N U00939, Rev. 08/14/2014).

The PSL is now up and running after this morning's power glitch.  Once the front ends were alive the PSL came up without any issue.  I reset the injection locking relock counter.

While it was down I took the opportunity to power cycle the diode chiller.  The front panel of the chiller has been scrambled since the chiller started behaving funny (alogs here and here), the power cycling cleared the screen up; the water temperature is still oscillating.  We are in talks with the chiller manufacturer about this issue.

TITLE: 09/30 Day Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Power glitched -- Front Ends are down (but Beckhoff seems to have survived). Waiting for people to show up to help with the recovery.
INCOMING OPERATOR: Corey
SHIFT SUMMARY: Kiwamu and Stefan left the interferometer locked and asked me to touch knobs to try to reduce broad bump around 100-1kHz. I gained about 15 Mpc by putting -0.05 offset to CSOFT pitch and CSOFT yaw (details and pretty plot in alog30085) but didn't get rid of the mysterious bump. Terra was here all night dealing with PI.

LOG:

13:08 Power glitched

13:29 Richard to CER

13:31 Richard going to power cycle stuff at end station

14:41 Jeff B. going to EX to check on dust monitor vacuum pump

14:56 Jeff done at EX, going to EY.

14:59 Turn over to Corey

Tasked by Kiwamu and Stefan to turn random knobs in a hope of getting rid of 100-1kHz bump, I was able to gain 15 Mpc by adding -0.05 offset to CSOFT pitch and yaw. I haven't had a chance to try every ASC knobs due to the power glitch. We were at 75 Mpc before the IFO went down.

Here's a note on everything I've tried (all time in PT):

3:40 added/subtracted 0.02 counts to H1:LSC-MOD_RF45_AM_RFSET -- Nothing improved

3:46 Added +6 gain to PRC1 LSC -- 27 Hz line became visible. But later found this line to come and go so this could totally be a coincidence

3:52 Changed CO2X power to 1W -- quickly dropped the power back to nominal when I realized that it's probably going to take a while to see the result

4:38-4:58 [In ASC land] Played with CSOFT pitch and yaw offset -- Settled at -0.05 for both. Slightly improved overall DARM spectrum but made 20-30 Hz wrose. Gained 15 Mpc in range here (if it's not calibration that's fooling with me). Any more negative number added would decrease AS90/POP90.

5:06 Added -10 to CHARD pitch -- nothing improved

5:13 Added -0.07 to CSOFT pitch -- nothing improved

5:14 Added -20 offset to CHARD yaw. -- Nothing improved

5:17 Added offset to DHARD pitch -- Nothing improved

5:27 Added offset to DSOFT pitch -- Nothing

5:48 Added -0.05 offset to DSOFT yaw -- Increased AS90/POP90 but no obvious approvement in DARM.

5:58 Added -25 offset to INP1_Y -- improved AS90/POP90 but no apparent improvement in DARM spectrum

6:08 Power glitch. Meh.

I also moved PR3 and changed something on SRC1 but didn't write down details (since it probably was not doing anything).

I put everything back in place before the power glitch except for the CSOFT gain that worked. I turned off all the gain buttons that I turned on except for CSOFT P and Y but not neccesary return the gain number back to what they were. I have them all written down though.

Continuing our look at the test mass drumhead modes, I've set up damping filters for 

MODE5 ITMX Drumhead 8162 Hz , MODE12 ITMY Drumhead 8161 Hz

Was able to predict which drumhead frequency corresponded to which test mass based on frequency shift during previous night's 4 hour lock: known ~15kHz modes of ITMX shifted 0.09 Hz over the four hours, ITMY shifted 0.13 Hz over the four hours. Accordingly, 8162 Hz shifted 0.07 Hz and I was able to ring up on ITMX. 8161 Hz shifted 0.11 Hz and I was able to ring up on ITMY. Torsional modal frequency is proportional to sqrt(G/p) and longitudinal modal frequency to sqrt(E/p) where G is shear modulus, E is Youngs modulus, and p is density (see P080069).

We had minimal PI issues through the night; most PI related locklosses over the past week could've been prevented with simple early-action small phase changes and tonight reinforced that. Jim and Nutsinee were both successful at damping; I fixed Jim's earlier problematic MODE17 with a filter change and the rest of the 4.5 hour lock went smoothly, requiring only one phase tweak a few hours in.  We lost lock from the power glitch. 

We just had what appears to be a site-wide power glitch at 13:08 UTC. All front ends down. Richard is here and starting power cycling. 

- Tried switching the guardian back to using REFL WFS instead of POPX WFS for PRC2. This is simply a boolean variable change in lscparams.py: use_popx_wfs = 0. We also updated the the beam diverter closing state to also use the same boolean variable.

- However, we need to retune the REFL WFS at the new modulation index - we saw the loop run away in Nominal Low Noise,

- We also tried to repeat the jitter coupling reduction with INP1 offsets. While the transfer function again was reduced, the ASC loops were having problems with the large offset - we saw CSOFT ring up at 1Hz. Also there was a 3Hzish signal visible in CHARD and CSOFT. So much for reproducability...

- Next we also tried a CHARD YAW offset. Indeed -3500ct in CHARD YAW started bringing down the IM4 YAW jitter coupling. As suspected this probably means we simply cancel an unknow coupling with a deliberate misalignment induced coupling.

I've updated the PI Damping Operator Wiki with step-by-step instructions for damping PI's. These instructions cover basic damping for modes we already know about and repeat exactly what I've worked through with almost all of the operators by now. They should be enough to walk you through damping most modes that might ring up during a longer lock. We've also added a verbal alarm to alert you if a PI has started ringing up. 

Wiki can be opened from LHO Ops Wiki ('PI DAMPING') and from PI Overview MEDM screen:

Many thanks to Nutsinee for the awesome edits. 

(Betsy, Gerardo)

This morning added 500 ml of water, and walked/crawled the length of the pipe looking for water drops, none found.  The inside of the TCS-Y table was not inspected.