no restarts reported.

model restarts logged for Fri 25/Apr/2014
2014_04_25 16:35 h1lsc

no unexpected restarts.

EY tripped, recovered, I started realigning Y arm, and at some stage when the arm transmission started to become decent the transmission number started jumping back and forth.

At first I was tempted to think of this as a HOM-related fluke, but when I looked at the time series, it looks as if some incorrect bits are flipped at certain number (though the data is already decimated to 2kHz and the decimation filter should make things somewhat fuzzy).

I'll connect a function generator or something to this channel and see what's going on on Monday.

After Richard fixed the issue with the ETMX ESD (see alog 11573) this morning, I briefly took an angular transfer function of pitch and yaw using the oplev. They don't look crazy -- 1/f^2 shape and non-measurable crosscoupling between pitch and yaw. However there was a descrepancy from the model predictions by a factor of 2-ish. I am not sure what makes the descrepancy for the moment. The transfer functions are shown below with the models for comparison.

Anyway, the ESD is functional and ready to go.

Note that I included Jeff K's arc-integral-factor which gave an extra factor of 2/pi for the torque in the model. For those who are interested in the details of the calculation, please find it in the attachment (ESD_pitandyaw.m). The raw data are attached as well.

I believe I have ameliorated the wireless problems with the workstations at EX.  Let me know if they continue to misbehave.

Also, I rebooted the dedicated vacuum workstation in the control room since it was running terribly.  It's also had the latest updates applied.

Sheila, Alexa, Stefan, Daniel

Attached is a spectrum, in Hz/rt Hz, of the PLL control singals for ALS diff and COMM.  This looks simliar to what was measured at Livingston last week.

We made changes to the LSC model to route these control signals into the input matrix to allow us to lock ALS DIFF. 

HAM2+3  HEPI and ISIs have tripped along with MC2+PR2.  We have seen similar behavoir before after a beckhoff restart, but this time it was the LSC model. 

The LSC model restart would have killed the guardian, and unlocked the modecleaner, meaning that the integrator at the top stage of MC2 would get saturated, so it makes sense that MC2 tripped.  The ISIs and HEPIs weren't payload trips, so something else is going wrong. 

This probably could have been prevented if I unlocked the mode cleaner and puased the guardian first.

Here is an error message from the plotting script failing:

  File "/opt/rtcds/userapps/release//isi/common/scripts/wd_plots/main.py", line 170, in _BufferDict
    abs_threshold_mask=abs_threshold_mask, host=host, port=port)
  File "/opt/rtcds/userapps/trunk/isi/common/scripts/wd_plots/pydv/bufferdict.py", line 243, in __init__
    self.add_channels(channel_names, wd_state_mask=wd_state_mask, abs_threshold_mask=abs_threshold_mask)
  File "/opt/rtcds/userapps/trunk/isi/common/scripts/wd_plots/pydv/bufferdict.py", line 382, in add_channels
    abs_threshold_mask=abs_threshold_mask)
  File "/opt/rtcds/userapps/trunk/isi/common/scripts/wd_plots/pydv/bufferdict.py", line 344, in __fetch_data
    self.conn.clear_cache()  # clear any saved information from a previous connection
RuntimeError: Input/output error
 

9:00- 10:45 Getting ready to remove payload on HAM5 – Hugh and crew
9:05- 10:00 Performing PET swipe at HAM 5 – Jeff  B.
9:25- Doing inventory by the squeezer bay area – Corey
9:43- Moderate dust  alarms  at both end station 
10:00-11:55 Working at End X-Richard
10:06 PSL check (Done)
10:07: 11:30 Heading to End Y to work on dust monitors – Jeff B. 
10:40 Moving laser barriers around the HAM4 TCS table area – Justin/Cris
11:02-12:45 Heading into H2 Laser enclosure to set up the OFI - Gerardo 
12:37 Heading to End X (cleaning) – Chris
12:49-14:16 Heading to Mid Y (cleaning) – Karen
13:27 Running hose from near HAM4 to inside Diode Room – Jeff B.
13:36-14:48 Back to H2 Laser enclosure to set up the OFI - Gerardo
13:44-14:48 Joining Gerardo in H2 Laser enclosure (LVEA) – Mark B.
13:45-14:41 Setting signs around TCS area in LVEA – Justin
14:47 Beckoff power recycling – Matt/Greg
15:25 Heading to End X to fix CDS workstations - Cyrus

This exercise will need to be done occasionally until the Y2-1 port is restored to its nominal configuration (i.e., following the removal of the RGA test setup)

Finally installed all of the cabling and interlock boxes for the ESD drive.  There is a short cable at the feed through that goes to a current limiting resistor box.  From that box a 5 conduct cable with SHV connectors goes to the ESD amplifier.   The ESD amplifier has +-430V dc and +-18v dc supplied to it.  The HV supply is interlocked to a Vacuum gauge on the chamber.  

One item of note for the installation is the SHV coax cable label 1 goes to ESD amp port 3 and Coax cable 3 goes to ESD amp port 1.  I have used sharpie to mark this.

If the vacuum gauge trips the HV supply or if we have a power outage the HV supplies need to be switched on by hand.  The +430 Volt supply was found in Sink mode.  I am not sure how it arrived in this state because you would have to program the unit to do this and when the unit was turned on this was not done.  WE WILL have to track this to see if it is a problem. 

Before connecting the unit to Vacuum I checked the output values.

With See Table on attached pdf


								

HEPI was locked(put on stops) a couple days ago but its sensors remain on.  At the same time, the ISI interface electronics were powered down to allow decabling the air side.
This morning the ISI was locked (with lockers) and then the 800lbs of dummy payload was removed to make room for Suspension installs.
Thanks to Apollo Scott, Mark & Bubba.

ITMX tripped, this might have been a result of Jim's measurement, but I am not sure. 

The gps time was 1082487591

A ZFL-500LNB+ Mini-Circuits amplifier was added to the output of the COMM PLL BBPD. It is mounted directly to the output connector of BBPD using a SMA barrel. This amplifier was measured to have 29dB-30dB of gain in the 80MHz frequency range. Currently, there is a power supply on top of the enclosure. Longer term, we want to splice this into the +/-15V supply running to the BBPD. All other amplifiers were removed from the path.

8:15-8:35

Mike, Terry, Pablo, Daniel, Steban, Vern, Justin, Richard, Bubba, Kiwamu, Jim, Hugh, Mark, Jason, Aaron, Mitchell, Mark B., Keita, Jeff K.

LVEA is Laser HAZARD

HAM4- Cleaning crew in action – Karen and Chris
Craning activity by APOLLO
HAM5 ISI:  Removing payload –Hugh/Apollo 
TCS tables work continues. David/Aidan
TCS racks work at end stations (Richard & crew)
3ifo BSC ISI assembly  work continues in Staging Building – Mitchell
Dust monitors work at end stations. Switching the dust monitor unit in diode room. Jeff B.

no restarts reported.

Jim and I pulled/pushed all of the blade springs and installed flexures on unit 2 yesterday. Parts needed for unit 3 were discovered to be short of needed quantities have been ordered.

Alexa, Sheila, Stefan

Our goal today was to get a good diff readout going. For this we
- Commissioned the IMTY and ETMY optical levers, See snapshot.
- Recommissioned the x-arm dither - turns out the phases were tuned up for a different suspension setting - we need configuration control on all the suspension settings. Also see the snaphot.
- With that we got fairly stable arm locking - at least for a while - see below.

- Next we tweaked up the DIFF beat note on ISCT1. We got -20dB signal out of the PD.
- Th PLL locked for short stretches, but essentially always runs out of range after a few seconds.

- Thus we decided to work on top-mass slow feed-back: There was a lot of confusion, but once everything was done right, it sort of worked.
- One thing we noticed along the way, is that our 1-3Hz BLRM traces pick up increases in noise with an roughly hourly periodicity. This noise somehow translates into extra length motion at 0.05Hz. 
- We also fine-tuned the ETMY top mass L2P filter - see Arnaud's log
- The slow feed-back gain was however limited by our main suspension resonance, which meant that we couldn't suppress the DIFF motion enough.
- We thus decided to work on the L2L filters, which should give us the ability to increase the UGF of that loop and get more suppression.
- We got a simple L2L measurement going, but more work is needed.

Mark B. and Gerardo

Yesterday (4/22/14) Gerardo and I measured the vertical mode Q of the OFIS for three different positions of the ECD block to try to get the Q in the specified range of 25-30.

The OFIS was set up on the optical bench in the H2 laser enclosure. The ECD block sits on a tray below the payload which is supported by four groups of vertically pointing screws at accessible positions around the edge of the structure. Gerardo had earlier attempted to set the ECD block at the nominal height using the spacer tool provided but found that this was too high and caused interference. He therefore lowered the block until it was just barely clear plus approximately an extra two turns of the 1/4-20 screws. This was our starting point for further adjustments.

To measure the vertical Q, we used the laser pointer and QPD from the monolithic violin mode setup and used a convenient screw on the top of the payload to partially block the beam. We displayed the "pitch" output of the QPD box on a digital oscilloscope with a 1 sec/div timebase and photographed the screen to capture the data. I read off the peak positions with GraphClick, and worked out the logarithmic decrement and Q with Mathematica.

For the initial position, the Q was 10.7. We lowered the ECD by one turn on all the screws and got Q = 18.9. We lowered the ECD another half turn and got Q = 23.3. Finally, today (4/23/14) we lowered the ECD another 3/4 turn and got 27.8, which is in spec.

Attached is a JPG of the setup, a PDF of all the screenshots, and for the fourth and final run, the Mathematica notebook, PDF thereof and the raw data.