HEPI TF's running over-night on ITMX. Opsws1.

Existing cable needs to be re-routed to make room for new oplev pier but it is too short -> Replaced short cable with long one borrowed from the Corner Station turbos 

I tested the minimal interlock functionality (QDP80 PUMP RUNNING) of the new cable by demonstrating that the turbo safety valve closes when the QDP80 is stopped remotely with the safety valve in the "ROUGH" or "TURBO" position.  

I did not test the other signals used on this cable, i.e.,  "QDP80 TEMP WARNING", "QDP80 TEMP HAZARD" and "N2 FLOW WARNING"

I noticed that the ODC channel for the IMC was not happy. Tracked it down to some saturation in the WFS A and B inputs, presumable due to the input power increase.
I lowered the whitening gain lowered to 36dB (was 45dB).

I also readjusted some thresholds on the IMC ODC screen:
H1:IMC-ODC_DOF[1|2]_[PIT|YAW]_ERR_MAX 10000
H1:IMC-ODC_MC2_TRANS_SUM_MIN 2000
H1:IMC-ODC_IM4_TRANS_SUM_MIN 15000

A temporary RF power splitter was installed in both REFLAIR_B and POPAIR_B RF paths. They will be replaced by diplexers once they are ready.

The attached is a picture of the RF power splitters installed on the ISC R2 rack. In some future, we might add RF filters in order to cut off unnecessary RF signals.

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See attached for the watchdog trip plot.  Interesting in that the T240s see a slow tilt on horizontal channels and this trips the system.  There is a 4.9 EQ about 26minutes prior south of South Africa but it is shallow and maybe too small/too far...  May not be related.  I've put the ISI back in lvl2 isolation.

I adjusted the demodulation phase of the REFLAIR_A photodiode in the delay line phase shifter by toggling the physical switches on its front panel.

Right now, the phase is adjusted such that the length signal from the power recycling cavity shows up in Q which is opposite to the usual signal convention. Because the phase shifter could rotate it by roughly 100 deg at 9 MHz which was not big enough to get the I signal maximized for the power recycling signal, I ended up with the Q signals maximized. The adjustment was done by letting the PRX cavity freely swing and taking a look at the I and Q monitors of the demodulation board with an oscilloscope. The attached is a picture of the resultant physical switches after the adjustment. Note that it is set to be the internal switch so that the digital system can not mess it up.

I don't feel comfortable with the degree to which GV5, GV7 and GV20 are "soft-closed" for the unattended worst case scenario -> Switched YBM turbo from being backed by its QDP80 to the safer state of being backed by the LD which has its own, redundant, energize-open isolation valve -> valved-out XBM turbo 

The solenoid-actuated air manifold which switches instrument-air from either the bottom or the top of GV7's piston leaks unpredictably when the applied air pressure is low, i.e. with the nominal 5 psig applied when GV7 is soft closed.  For instance, if the regulator is isolated from the manifold and an output of 5 psig is selected this pressure falls to 0 psig when valved-in to the manifold and stays 0 psig regardless of how much time elapses.  If the applied pressure is increased the audible "hissing" past the leak increases but the piston pressure remains 0 psig - to a point. If the regulator output pressure is further increased eventually the pressure at the piston will "come on scale" but the leak rate will often change simultaneously and then the desired pressure applied to the piston will be exceeded and GV7 may cam hard-closed etc. (GV5 doesn't do this)

I moved the newly assembled scroll pump+sentry valve+relay box assembly out to the X-end station and am running it in standalone mode to get some hours of running on it before using it in place of the X-end turbo's QDP80 -> Once in use, the failure mode for the X-end turbo will have two layers of protection.  

References: D1201036 (BSC9 ACB assy) and D1200314 (BSC3)

Gerardo read the distances between the baffle diodes off of CAD drawings for me (see the attached cartoon). 

ITM baffle PD1-PD4 separation is 11.3" over 4km (72 urad) both horizontally and vertically. For ETM the number is 11.8", so it's 75 urad.

Don't know why the patterns are different for ETM and ITM, but using these we can calibrate TMSX, ITMX and ETMX bias sliders. Note the factor of 2 between TMS and mirrors, this is because TMS moves with the beam but mirrors don't.

Calibration of ETMX is somewhat suspect (at 10urad level) because of the fact that the position loop of EX ISI got accidentally off before I did ETMX adjustment.

Attempted to reengage the ISI Isolation with the added tilt of HEPI.  This HEPI tilt swings the ISI such that the current free hang location of the CPS is too far from the previous position.  The T240s ring up and trip the process.  I attempt to get there by first setting the Current Setpoint to current location (there's a button for this) and of course that worked until the latter part of the script tried to drive the CPS back to the free hang position.  So, I then further pushed the Current location into the Target position.   This of course did work cause it basically drives the ISI nowhere and doesn't kick/tilt the T240.  But, the ISI now operates in this tilted position.  To get it back we'd just need to untilt the HEPI and reset the ISI setpoints and targets.

Back to the Isolation operation, last Friday JeffK & I noticed the ISI drives growing after being at lvl3 isolation.  These rang up and tripped on Actuator drive levels.  I set the ISI to lvl1 isolation and pulled out a book.  No noticible ring up after several minutes.  So I controlled down and went up to lvl2 isolation.  Again, several minutes and no problem.  Not sure if I waited long enough but...

Then I ctrldown and put it in lvl3 isolation.  Sure enough boost2 was engaged rather than boost3.  I left it be and after running pretty well about 15 minutes the drives started to ringup mostly in Stage2 Verticals but other channels as well.  I ctrldown next and then brought it back to lvl3 again but now switch from boost2 over to boost3 right away.  Again the drive rung up after about the same amount of time.  I should have been watching the spectrum before it rang up but I again had dtt troubles.  When I did get it running the drives were already excited.  Looking at the spectra I saw a tall peak at 147hz.  I then did a ctrlDown and saved the trip.  As the spectra quieted down, the 147hz peak withered.  Better to see this pop up while steady state rather than disappear after ctrlDown but it maybe what is happening.  One thing I notice in the trend is that it looks to stop increasing in amplitude after a time.  See attached.  Maybe it would settle back down or maybe it eventually trip the watch dog but I didn't give it that chance this time.

In the attached plot you see the Master Drive going up and down as the isolation is engaged and ctrlDown'd.  The lvl3 isolation is the last two wider segments.  Notice the ramp up of the signal stops after a time and goes flat before I ctrlDown.  Again so very interesting...

I've set the isolation to lvl2 for now; looks OK after about 20 minutes.

LVEA Laser Hazard

Apollo - Install HAM1 door
Hugh – End X to work on HEPI  

08:30 Keita transitioned LVEA to laser safe while Apollo crew installed the HAM1 door
09:45 Apollo finished installing HAM1 door
10:45 Keita transitioned the LVEA to laser hazard
11:00 Hugh & Mitch at End X to work on HEPI
11:50 Dave did a remote DAC recycle to pick up new Beckhoff channels

Merry Christmas to one and all

The photodiode amplifiers for the fiber transmitted and rejected beams were not behaving as expected. Changing the gain had seemingly no effect on the read voltage. The first problem was that the two diodes were crosswired in the slow controls system. However, this did not fix the problem, and it is the same for the IR DC power. It looks like the gain settings are not getting applied to the concentrator. The main suspects are the 5V supply, DC_6, in the end 2 chassis, or another of these DB37 cables with pin 19 conveniently left unconnected. This supply is used to power the binary IO terminals for auxiliary concentrator 5. It also controls the gain in the REFL PD DC path.

Combined volumes of HAM2, HAM3, YBM, BSC1, BSC2, BSC3, XBM now pumped by both YBM and XBM turbos backed by QDP80s

Andres R. & Jeff B.

   We suspended H1-SR2 with the metal dummy mass installed. Checked several of the critical measurements to make sure nothing was disturbed during the transport of the suspension to the LVEA. All measurements are within specifications. 

   We centered the BOSEMs and took a set of transfer functions for phase 1b testing.
 
   The TF plots are attached below. There is some noise below 1Hz. However, as we are going to swap out the bottom wires, the M3 mass, and rework the suspension anyway, spending much time tracking down and fixing this noise is not a high priority.     

I saw no sign of real work in BS M2 coil balancing, I had some time, no SUS person was around, so I started doing it manually.

Coil gains before/after the adjustment:

Seems like the balance was not that bad anyway. I removed funny overall factor of 1.23 as I and Jeff Kissel agreed last week.

It may not be a big deal depending on how HEPI is used but the Inductive Position Sensors are close to their limits.

With Keita applying -12000 somethings offsets in the Blend for Ry, V1 & V2 are close to 30k counts on the IPS.  I increased this to -13000 to check that we still had some headroom.  First attempt tripped as the IPS watchdog is set at 30000.  Why isn't this 32000?  I increased the trip level and went to -13000 again.  All the IPS moved in response and the spread in readings was around 10% of the change so it didn't seem any one actuator was stuck.  Looking at the Dial Indicators though, the SW corner (2) moved down 6 mils while the NE corner (4) went up only 1mil.  The other corners shift 3mils each.  The magnitude of the moves make sense, the DIs average 3.25mils & the IPS average 2.76mils.  But the IPS are much more uniform than the DIs...  Could the V4 be hitting a stop, hard to tell but it didn't look closer than the others.

While at -13000 Ry I checked the Actuators and they all looked pretty close to hitting their mechanical stops.

Removed the -13000 offset and checks the DIs & Actuators.  The actuators looked decently centered but the South side rebounded up more than the North side rebounded down by ~2x. There was also several mils of Rz displacement seen at the DIs.  Returned the -12000 offset an the IPS return to almost exactly where we started.

Couple things:

Much further actuation and possibly damping/isolation coud trigger the IPS watchdog with the current 30k limit.

Correcting the input matrix, installing the symmetrization filters and commissioning the loops would be good to get done.

I restarted the DAQ to accomplish two goals: install the latest Beckhoff slow channel configuration (including baffle pds and the return of EY) and reconnecting to the PSL Centroid channels.

I was successful with the former, not successful with the latter.

The PSL Centroid channels are still not connected, and the reason is there is no EPICS Gateway between the H1AUX and H1FE VLANS. I am not comfortable installing a brand new EPICS gateway on Christmas Eve afternoon, so I'll delay this install until later in the week when I am physically on site.

The number of slow channels the EDCU is acquiring went up from 19,311 to 21,328. Both of these numbers are 8 less that the total ini channel count due to the missing 8 centroid channels.