Displaying reports 57301-57320 of 83146.Go to page Start 2862 2863 2864 2865 2866 2867 2868 2869 2870 End
Reports until 21:20, Tuesday 12 April 2016
H1 SEI
michael.ross@LIGO.ORG - posted 21:20, Tuesday 12 April 2016 (26558)
BRS Software Upgrades
Krishna, Michael

The winds have yet to pick up so we spent the past two days working on software upgrades. 

At ETMY, we integrated our previous PLC code into Daniel's template which will bring our code closer to standards. There was an error in the PlcInfoFB structure which we didn't know how to fix so we commented out the call in the main program. Also, the previous state initialization was re-initializing our variables on every loop so we disabled that function as well. Besides those two errors, the program runs as expected.

At ETMX, we upgraded the C# code to closely match the version we use at ETMY. The most substantial change is in the pattern to angle algorithm. The angle used to be calculated from the average difference of the collection of peak pairs which involved fitting each peak to a Gaussian. The new algorithm involves calculating the cross correlation of the patterns with respect to pixel shifts of the main pattern which is then fitted to a Gaussian. These changes reduce the computation required for each frame while also decreasing outside dependencies. We hope this new version will remove the bug which caused the previous code to crash periodically.
H1 IOO (IOO)
cheryl.vorvick@LIGO.ORG - posted 17:07, Tuesday 12 April 2016 (26556)
IO IMs (IM1-4) aligned but damping is off

gathering free-swinging data overnight per WP5824

damping will be re-engaged tomorrow morning

LHO VE
filiberto.clara@LIGO.ORG - posted 16:59, Tuesday 12 April 2016 - last comment - 19:00, Tuesday 12 April 2016(26555)
EY - New Vacuum Control Sytem Installed WP 5822
Richard, Patrick, Filiberto

Beckhoff based vacuum control chassis and computer were installed at EY. Sorted out some issues with internal wiring for the 4-20ma inputs (LN2 gauges) inside the beckhoff chassis. Installed shorting plugs for the LN2 control valve watchdog. PT425, PT426, and PT427 guages were connected to the end Y vacuum chassis. We are still trying to sort out some issues with the readback signal for ion pump II411.
Comments related to this report
patrick.thomas@LIGO.ORG - 19:00, Tuesday 12 April 2016 (26557)
I have updated the control room alarm handler. I have also put the CP7 LLCV on PID control. It appears to be recovering well.
LHO General
corey.gray@LIGO.ORG - posted 16:01, Tuesday 12 April 2016 (26543)
Maintenance DAY Ops Summary

Fairly busy full day of Maintenace today.  The HPO work continues.  The hope is for beam to be back tomorrow.

Day's Activities

H1 ISC (PSL)
kiwamu.izumi@LIGO.ORG - posted 15:43, Tuesday 12 April 2016 (26554)
LSC model change: a 3rd intensity stabilization loop implemented

WP 5823

I have edited the h1lsc and common lsc models in order for us to be able to route the TR signals to the intensity stabilization system. As a result, the LSC model is now able to output a linear combination of TRX_NSUM and TRY_NSUM through a DAC. This signal can be then routed via an analog cable to the ISS, enabling us for a 3rd ISS loop.

To really engage this loop, one still needs to pull a few meter cable from the DAC output on the ISC field rack to the ISS module (either TRANSFER_1 or _2 analog input) in the same rack area. Additionally, to shave off undesired DAC noise above 10 Hz, we need an SR560 or equivalent in this analog path.


[Modification on the common lsc model]

 I have added two new outputs. Because the TRX and TRY were already acquired in LSC and properly normalized, only things I added are two "From" tags and two outputs. The modified version is uploaded to SVN. For LLO, they can just terminate these two outputs at the top level until they need these signals.

[Modification on the h1lsc model]

I have added a new subblock called "PSL_ISS" in which I placed a matrix to combine the TRX and TRY signals and placed a filter. The output of this subblock is then routed to channel 11 of DAC0. Because DAC0 was occupied by an unused channel ALS_STATE_A, I have disconnected and terminated ALS_STATE_A. This should not impact on anything. The model is checked into SVN. After the installation of the new model, I checked the output signal with a voltmeter at the floor and it was doing what it should do.

[Medm screen]

I made a medm screen for this new ISS loop. It is accessible from the PSL tab on SITEMAP. This screen is also checked into SVN.

Images attached to this report
H1 CDS
patrick.thomas@LIGO.ORG - posted 14:38, Tuesday 12 April 2016 (26552)
Fixed text entry for medm on h0veex
Created system environment variable XKEYSYMDB and set it to 'C:/Program Files/Xming/XKeysymDB' (with backslashes instead of forward slashes).

http://www.aps.anl.gov/epics/tech-talk/2007/msg00075.php
H1 CDS
patrick.thomas@LIGO.ORG - posted 14:35, Tuesday 12 April 2016 (26551)
Accidently disabled CDS NIC on h0veex
Drove to end X and re-enabled it.
LHO VE
kyle.ryan@LIGO.ORG - posted 14:31, Tuesday 12 April 2016 (26550)
Found in-house vacuum cleaner running unattended at X-mid
I noticed during my site inspection that the X-mid in-house vacuum cleaner was running for some unknown reason -> I unplugged it.
LHO VE
kyle.ryan@LIGO.ORG - posted 14:29, Tuesday 12 April 2016 (26549)
Restarted IP8 (loose HV connector)
Chandra, Kyle 

Chandra noticed that IP8 had shut-down.  The LPC controller was displaying an error "High Voltage not detected" -> This error isn't listed in the "list of error codes" but was the result of a loose HV connector in the back of the controller -> Deenergized controller, reseated connectors, pwrd on - OK now.  
LHO VE (VE)
gerardo.moreno@LIGO.ORG - posted 11:44, Tuesday 12 April 2016 (26547)
CP3 Liquid Level Control Change @ 18:32 utc

After a LN2 delivery the liquid level control valve setting was lowered to 18%, previous setting of 20%.

H1 SEI (SEI)
corey.gray@LIGO.ORG - posted 09:19, Tuesday 12 April 2016 (26545)
OPS: Reset of HEPI L4C Accumulated WD Counters Tues April 12th 2016

Per the Ops Daily Checksheet for Tuesday, I reset the following HEPI L4C Watchdogs:  HAM3, HAM4, HAM5, ITMx, BS, ETMx, & ETMy.

LHO VE
corey.gray@LIGO.ORG - posted 08:24, Tuesday 12 April 2016 - last comment - 09:10, Tuesday 12 April 2016(26542)
"Vacuum Pressure High" Verbal Alarm This Morning

Have had this alarm since about 3:39am (10:39utc). 

(However, not sure what channels this is looking at.  HAM6 is hovering around 10^-5 Torr, but it's been trending low since yesterday afternoon.)

Comments related to this report
thomas.shaffer@LIGO.ORG - 09:10, Tuesday 12 April 2016 (26544)

The reason for the repetition of this alarm is that the the channel HVE-LX:Y0_110BTORR has been passing through the threshold value (1e-5) since about 10:35 UTC. When we vented it just reported this alarm once, as it should, and then stayed "in alarm" until now. As it has been pumped down, it will switch from being "in alarm" to no alarm and then back forth again. I have turned off Verbal for now as to not annoy the entire control room. The point of the vacuum system alarm in the Verbal system is not necessarily to catch a failure of some sort, the vacuum and CDS teams already have a system in place to alert any sudden changes of pressure and inform the correct people. Rather, it is just a way to inform the operator that one of these failures have may have occured and to make sure that the correct people have already been informed or that venting has truely began.

A possible fix for this is to average the channels over some time, but taking these averages adds a significant amount of time to the loop. Since venting is a very rare event, I think we can just live with it. I don't see any problems with turning off Verbal for a handful of hours while it settles past this threshold. Option B would be to remove this test from Verbal entirely. As I previously said, the VE system is already monitored by other, more precise, systems but my worry is that the operator may not know if there was something going on.

Attached a trend of the channel .

Images attached to this comment
H1 PSL (PSL)
peter.king@LIGO.ORG - posted 05:06, Tuesday 12 April 2016 (26541)
Power stabilisation status
The light level on the first loop power stabilisation photodiodes was adjusted to
give ~9.6V on PDA and ~10.2V on PDB.  Other than (mis)aligning each photodiode there
is no way to adjust the output of each separately as the half waveplate is common
in both paths.

We tried engaging the power stabilisation servo without success.

The DC output voltage of the photodiodes reported on the MEDM screen are different from
those measured by a voltmeter.  Even though these DC values are calculated from the AC
output, once the value exceeds ~7V the discrepancy becomes quite large with 10V as
measured with a voltmeter being reported as ~6V on the MEDM screen.




Jason, Peter
H1 PSL (PSL)
peter.king@LIGO.ORG - posted 04:58, Tuesday 12 April 2016 (26540)
Frequency stabilisation status
The transfer function measurement of the frequency stabilisation servo are attached.
The unity gain frequency is ~180 kHz with a phase margin of ~25 degrees.  Recall that
because of the way the readout monitor ports are, the unity gain should read at -10dB.

The measured values are a little lower than what was measured with just the front end
laser running.  Although not too far off.

Not quite sure what the dip in the magnitude around 25.5 kHz is but it might be related
to the injection locking electronics.

The current gain slider settings are fast gain = 22 dB, common gain = 16 dB.  The output
of the RF photodiode is 50-60 mV locked, 230-320 mV unlocked.


Jason, Peter
Images attached to this report
H1 PSL (PSL)
peter.king@LIGO.ORG - posted 03:40, Tuesday 12 April 2016 (26538)
Pre-modecleaner status
The power incident on the pre-modecleaner was increased from ~30W to ~138W.
The power transmitted by the pre-modecleaner, as measured by a power meter
located right after the pre-modecleaner, was ~123W.  This is consistent with
the visibility measurement conducted last week.

The transfer function for the low and high power modes are similar.  In the
high power mode, the unity gain frequency was ~6 kHz with a phase margin of
~ 80 degrees.

There is a problem with the transmission photodiode.  Whilst the filter
file for the photodiode appears to be okay, the output of the photodiode is
not consistent with the amount of incident light.  For the factor of ~4
increase in light power we observed an increase of less than 1 in the
photodiode output.  This problem does not show up in the low power mode.
The photodiode was given a cursory inspection and appears to be okay.  The
signal cable was temporarily swapped but made no difference.

This is a 2mm InGaAs photodiode (D1002929).  I suspect one of the voltage
regulators is sporadic.  Perhaps the LM317S providing the bias voltage.
This will be checked later today.

Jason, Peter
Images attached to this report
H1 PSL (PSL)
peter.king@LIGO.ORG - posted 03:09, Tuesday 12 April 2016 - last comment - 03:41, Tuesday 12 April 2016(26537)
PSL work
Transfer functions of the injection locking servo electronics were taken.
The previous measurements from when the PSL underwent acceptance testing
are posted in the DCC under
  https://dcc.ligo.org/DocDB/0100/E1300129/001/tf.pdf
That result listed the unity gain and phase margin as being 2.8 kHz and
57 degrees respectively.

With the previous setting of gain = -1.50V, the unity gain is ~8.5 kHz
with about 40 degrees of phase margin.  Setting the gain to -1.70V, upped
the unity gain to ~10 kHz.  This is consistent with the acceptance test
result from L1, which is in the DCC under
  https://dcc.ligo.org/DocDB/0068/E1100716/006/injection_locking_tf.pdf

Also attached is the oscilloscope image of the injection locking error
signal.



Jason, Peter
Images attached to this report
Comments related to this report
peter.king@LIGO.ORG - 03:41, Tuesday 12 April 2016 (26539)
Attached are spectra of the injection locking servo mixer monitor and
high voltage monitor output.
Images attached to this comment
LHO VE
chandra.romel@LIGO.ORG - posted 16:51, Monday 11 April 2016 - last comment - 09:28, Tuesday 12 April 2016(26533)
GV 5 & 7 open
Kyle, Chandra

Opened valves that were soft closed a week ago. 
GV 7 needed 40 psig. GV 5 needed 45 psig to open. 

Attached is plot of pressures on either side of each valve before and after opening. Before we realized to pump the gate annulus after a week, we had already set pressure against pistons to 20 psig, shifting gate slightly and releasing annulus gas into beam tube.

Images attached to this report
Comments related to this report
kyle.ryan@LIGO.ORG - 09:28, Tuesday 12 April 2016 (26546)

The take away from this observation is that O-rings of GV5 and GV7 must have been in full contact with their sealing surface whilst soft-closed, i.e with 5 - 10 psi applied to the top of their pistons.  This is as intended.  Had they not been in full contact, the gate annulus volumes would have been pumped by the adjacent vacuum volume(s) and no gas release would have occurred when the gates where stroked open.  Typically we would have "burped" the un-pumped gate annulus volume into the rest of the annulus piping before opening the gate valves.  

In summary, soft-closing GV5 and GV7 does provide protection to the Beam Tubes.
H1 ISC (ISC)
jenne.driggers@LIGO.ORG - posted 10:22, Monday 11 April 2016 - last comment - 14:47, Tuesday 12 April 2016(26521)
Terminated LO inputs of AS 90 WFS

I have terminated the LO inputs to the AS 90 WFS chassis (as well as the cables that normally go to these ports), so that we can see if the dark offsets are more stable without the triplexer.  Later today, I'll swap the terminators to be at the front of the triplexer box, to see if that changes things.

Comments related to this report
jenne.driggers@LIGO.ORG - 14:47, Tuesday 12 April 2016 (26553)

I have reverted this back to its nominal configuration.  It looks like the signals got much cleaner on 9Apr, around 10UTC, so I want to see if they are still clean after going back to the nominal config.  I can't find any cables that seemed bumped or out of place from the vacuum team's work, although they were working in the HAM6 area on both Thursday and Friday last week.

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