[Stuart A, Arnaud P]

Damped TFs had been taken on MC2 back in August (see LHO aLOG entry 13346), but had not been processed until now:-

- MC2 M1-M1 undamped TFs (2014-08-11_1091848686_H1SUSMC2_M1_damp_ON_ALL_TFs.pdf)

Before the corner vent, MC2 had been exhibiting 1 Hz Pitch and 1.5 Hz Roll modes cross-coupling into the Vertical DOF, which had been exacerbated when the chamber had been pumped down to vacuum (see LHO aLOG entry 11383). This was suspected due to EQ stops being set too close and rubbing, which is captured in an Integration Issue #847.

After the most recent July corner station chamber incursion, transfer functions taken at Phase 3a (in-air) for MC2 showed no cross-couplings into the Vertical DOF (see LHO aLOG entry 13036). Having now pumped down, the damped Phase 3b (in-vacuum) MC2 M1-M1 TFs presented above, are clear of cross-couplings into the Vertical DOF.

Below is a comparison of undamped Phase 3 MC2 TFs (see allhstss_2014-11-24_Phase3_H1MC2_M1_Doff_ALL_ZOOMED_TFs.pdf), the plot keys are as follows:-

Blue Trace = Model (hstsopt_metal)
Orange Trace = H1 MC2 M1 (2013−05−25_1053525085), Phase 3b
Magenta Trace = H1 MC2 M1 (2014−07−28_1090619695), Phase 3a

The original MC2 cross-couplings into Vertical DOF were present in Phase 3a and then exacerbated going to Phase 3b. However, the recent in-air measurements show absolutely no seeds of a cross-coupling.

Below is a comparison of damped Phase 3 MC2 TFs (see allhstss_2014-11-24_Phase3_H1MC2_M1_Don_ALL_ZOOMED_TFs.pdf), the plot keys are as follows:-

Blue Trace = Model (hstsopt_metal)
Orange Trace = H1 MC2 M1 (2013−05−25_1053543407), Phase 3b
Magenta Trace = H1 MC2 M1 (2014−08−11_1091848686), Phase 3b

Furthermore, back in April, even the damped in-vacuum TFs showed the aforementioned cross-couplings into the Vertical DOF. However, this is again not visible in the recent damped MC2 TFs.

Summary:

The above measurements indicated that there is no longer any pitch or roll cross-coupling in the vertical DOF of MC2 and therefore, that after the July corner station chamber incursion that the suspension is clear of EQ stops rubbing.

This should prove sufficient to close the Integration Issue #847.

All data, scripts and plots have been committed to the sus svn as of this entry.

PSL laser weekly trends.

See attached for the time series of the process, all done less than thirty minutes.  HEPI isolates first time, ISI & IMC remained locked.  Keita says it looks good (enough?.)  I tweeked the RZ target ~100nrads to bring the ISI OpLev 'Yaw' (yes, still reversed) back to before reading.  I didn't tweek pitch but is within a couple 'units' on the ISI OpLev.

The signs changed on the RX RY & RZ with the matrix correction but all the amplitudes were correct.  The output matrix was a mess though and looks much better now--see second attachment for a before & after view of the matrices. The correct matrices are in the right column.

Updated safe.snap and foton txt file commited to svn r9202.

Searches unavailable for duration.

Work will be starting today on the new DCS area in the VPW as well as outside between the H-2 building and the VPW. Today's activities will include some shallow excavation work outside by George Grant Construction. Inside work will include hanging a temporary curtain in the VPW to isolate the construction area from the C & B area and layout for refrigeration lines by Apollo and George Grant.

model restarts logged for Mon 24/Nov/2014
2014_11_24 06:39 h1fw0
2014_11_24 17:43 h1fw0

both unexpected restarts. Conlog frequently changing channels report attached.

Stefan, Matt, Kiwamu, Evan, Alexa

• ALS DIFF and COMM are working great tonight with the ETMX L2P changes with the oplev running (see Stefan's alog)
• We lock DRMI+arms off resonance much faster if we bring the input power down to 4W, at which point we can easily transition back to 10W without breaking the lock. This is all implemented in guardian now.
• Kiwamu changed the gain of POP18 whitening gain by a factor of 4 because the ADC was saturating
• We added the SRCL mode hopping offset for DRMI+arms off resonance until the asc wfs kick in (the asc wfs turn on faster than before thanks to Dan's modifications, but still should be faster). We also made an edit to the asc wfs loops (see Matt's alog).
• We adjusted the REFLBIAS digital filters to reduce the amount of confusion -- we were compensating and un-compenstating for the same zero/poles with FM3, FM4. Now we just use FM6 (p1.6z40) to compensate for the Boost engaged in the COMM PLL Board to CM Board Path
• Since sqrt(TRX+TRY) goes as 1/f^2 we added a f shaped filter (FM9: z35:p1k) to match the 1/f shape of the ALS COMM loop shape
• The "right side of the river" for bringing the arm off resoance: set frequency offset should be -1000 Hz on the ALS COMM VCO. This has been updated in the guardian
• The ALS COMM FIND IR takes too long; especially the fine tune portion.
• We have transitioned to sqrt(TRX+TRY): With an ALS COMM offset of -150 Hz (green), we engaged REFLBIAS in the first input of CM board. I have attached a StripTool screen shot showing these loops locked; one can clearly see the noise reduction in the IR transmitted signal once we handoff. Some configuration stuff:
  • LSC-TR_CARM_OFFSET = -0.8
  • LSC-TR_CARM FM1 (to pm) and FM9 (z35:p1k) are ON
  • LSC_REFLBIAS FM6 (p0:z1),, FM9 (p1.6:z40) are ON
  • LSC_REFLBIAS gain 0.8
  • LSC-REFL_DC_BIAS gain 1
  • CM Inp1 0dB, CM Inp2 -4dB
  • We engage REFLBIAS gain first, then turn on FM6. Then we reduce CM INp2 down to -32 dB slowly and then turn off the input.
  • We use an ezca servo to adjust the ALS COMM PLL VCO offset so that we don't battle with the REFLBIAS input into the CM board.
  • This is all implemented in guardian CARM_ON_TR except for the CM inp2 ramp down.
  • We took a transfer function of sqrt(TRX+TRY) / CARM; this produced the expected 1/f^2 shape with a detuning peak at around the cavity pole of 40 Hz (see ALS_TR_HANDOFF.pdf -- The blue trace is without DRMI, ie PRM and SRM are misaligned with IR off resonance in the arm, while the red trace is with DRMI_arms off resoance in the configuration described above).
  • We also compared the REFLBIAS signal to the REFL_SERVO_SLOW_OUTPUT (which is essentially REFLBIAS + (-4dB)*ALS_COMM_PLL_CTRL). This looked as we expected. Stefan will add a comment.
  • We were able to increase the LSC-TR_CARM_OFFSET to -1.
• We only had to align the IFO once this morning!
• GPS 1100940241 at the end of the lock.
• Dear Dave, the load matrix is failing to load a lot.

LVEA: Laser Hazard
Observation Bit: Commissioning  

06:45 Karen – Cleaning in the LVEA
08:00 Tweaked the ISS Reference Signal voltage to raise Diffracted Power up to 8.5%  
08:47 Manny – In LVEA to check power racks near HAM2
09:00 Bubba & Mitch – Remove top from HAM ISI Storage Container and position Cleanroom
09:11 Filiberto & Aaron – At End-Y working on PEM power
09:13 Lockheed Martin locating services on site checking route to VPW
09:30 Cleaning crew – First cleaning on storage move cleanroom  
09:45 Bubba & Mitch – Finished in LVEA 
10:00 Bubba – Big-Red moving BSC Storage Container from LVEA Hi-Bay to Staging building
10:20 Added 300ml of water to Diode chiller
10:52 Bubba – Finished moving BSC Storage Container to Staging building
11:37 Filiberto & Aaron – Back from End-Y
11:50 Grant on site to deliver equipment for trenching work
12:35 Hanford testing emergency alarm system   

Alexa, Matt

In an attempt to get stable, if low-bandwidth, loops, we made some cut-off filters.

The new ASC filter in FM5 is:

LP0.2 zpk([0.0025+i*0.499994;0.0025-i*0.499994],[0.1+i*0.0979794;0.1-i*0.0979794;0.05+i*0.193649;0.05-i*0.193649],1,"n")

A couple of old filters that got lost were:

ASC_PRC1_Y FM5 "res1.35" resgain(1.35,10,10)resgain(3.16,10,10)
ASC_MICH_P FM5 "LP15_new" ellip("LowPass", 4, 1, 20, 15)cheby1("LowPass", 2, 1, 100)gain(2, "dB")
 

Aaron and I continued with PEM cabling at EY this morning. We have completed all long cables runs and started installing the permanent power supplies in the DC rack. We disconnected the power supplies powering the microphones in both the VEA and EBAY and placed them in the DC rack. Got a call from commissioners asking us to leave EY, before we could reconnect microphone power with permanent power supplies. Will go back tomorrow morning and power them up. 

PSL Status: 
SysStat: All Green, except VB program offline 
Output power: 33.2w  
Frontend Watch: Green
HPO Watch: Red

PMC:
Locked: 4 days, 16 hours, 33 minutes
Reflected power:    2.6w
Power Transmitted: 22.9w 
Total Power:       25.5w 

FSS:
Locked: 0 days, 0 hours, 43 minutes
Trans PD: 1.810v

ISS:
Diffracted power: 9.39%
Last saturation event: 0 days, 14 hours, 28 minutes  

Work on PEM power at End-Y
Locate Services on site Monday
Trenching work from OBS to VPW on Tuesday & Wednesday
Staging HAM ISI Storage container and Cleanroom in LVEA for 3IFO suspensions storage moves
HAM3 & BSC2 HEPI configuration work on Tuesday

When the modecleaner is kicked out of lock, the FSS oscillates and prevents relocking.

I've reduced the FSS common gain from 30 dB to 24 dB. Now the modecleaner relocks without issue.

J. Kissel, J. Warner, E. Merilh, H. Radkins

While taking down and bringing up the HAM2, HAM5, BS, and TM ISI + HPIs this morning to upgrade suspension front-end code (see LHO aLOG 14830), we had the following troubles with platforms:

(1) The Rogue Excitation Monitor for HAM5 ISI could not be naively reset, and was caught in a trip-loop.
     - First of all, it's frustrating that there in no MEDM screen indication that the MASTERSWITCH must be ON in order to reset the rogue excitation monitor, so myself / Jim / Ed spent a few minutes clicking all the watchdog reset buttons hoping that there was some special order, until Hugh informed (reminded?) us that the master switch needed to be on
     - Second, I'm not 100% confident why, but after enacting the "correct order" of reset by turning on MASTERSWITCH, reset Rogue WD, reset all to untrip the DACKILL, the MASTERSWITCH would turn itself OFF again before the three-second counter/delay of the rogue excitation was finished, therefore re-tripping thinking the MASTERSWITCH never was turned ON. I'm 90% confident this happened because the MASTERSWITCH would "turn itself off" because the SEI manager demanded that the MASTERSWITCH be OFF because it was still in the OFFLINE state.
     Why do we have the SEI Manager controlling the MASTERSWITCH, but the ISI module controlling everything else?

(2) There are no monitor signals on the MEDM overview screen to indicate what is currently causing the Rogue Excitation Watchdog to fire. This proved solving the above problem initially difficult -- I had to open the model to find out the logic (especially the hard-coded "100 [ct]" threshold), the three-second delay, open the CDMON channels in dataviewer, find they were low, and then go for figuring out the MASTERSWITCH trick. We should (a) added epics monitors on the three *inputs* rogue excitation monitor, and (b) create a sub-screen for the rogue excitation that reveals the details of this monitor.

(3) The BSC-ISI overview screens have the SEI Manager guardians on the overview screen. The BSC-HPI overview has the HPI module guardian. The HAM-ISIs and HAM-HPIs have their individual module guardians on the overview screen. This resulted confusion when trying to quickly bring the platforms back from offline -- I'd gone to the HAM-ISI overview after just finishing the BSCs, and out-of-habit assumed the guardian drop-down menu was the manager and was surprised why it wasn't doing anything for me. Arnaud informs me that this is because the overview screen mods were first made at LLO, where they're not using HEPI and therefore don't need a manager. Since not-using-HEPI is a deviation from aLIGO baseline, I argue that we should fix this by creating the SEI manager for the HAMs, and just temporarily create a managed configuration that doesn't use HEPI -- instead of having the confusing user interface for the HAMs.

(4) The SEI manager for ITMY seems to *not* automatically turn on the MASTERSWITCH. Is this automatic operation consistent between chambers? Between HAM managers and BSC managers?

(5) HAM3-HPI's L4C saturation counter in watchdog wouldn't reset with a RESET ALL or RESET above the current trigger but, but RESET WD ONLY worked. We can confirm that every other chamber behaves as expected, i.e. any of the three methods reset the counter. What's different about HAM3? Is this reset a python script that is uniquely defined per chamber or something?