Displaying reports 49081-49100 of 84635.Go to page Start 2451 2452 2453 2454 2455 2456 2457 2458 2459 End
Reports until 11:34, Thursday 01 June 2017
LHO VE (CDS)
david.barker@LIGO.ORG - posted 11:34, Thursday 01 June 2017 (36588)
CP3, CP4 overfill status

CP3 and CP4 auto overfills are now programmed to run daily instead of thrice-weekly (Mon, Wed, Fri).

CP3:

Chandra requested that today's CP3 auto overfill not run. This has been taking out of the crontab until further notice.

CP4:

CP4 ran at 11:02 PDT with the new configuration: daily run, cut-off temperature lowered from -60C to -100C. The attached trend shows CP4 thermocouple second trend data for 20 minutes for the last three runs (Mon 5/29, Wed 5/31 and Thu 6/1).

Images attached to this report
H1 ISC
peter.king@LIGO.ORG - posted 11:30, Thursday 01 June 2017 (36587)
Old ALS EndX laser
This morning I changed the settings of the ALS laser that was removed from EndX (InnoLight Prometheus S/N 2011B).
The pump laser diodes temperatures were left alone.
 - diode current                1.835 A
 - laser crystal temperature    24.92 degC
 - doubling crystal temperature 32.93 degC

    With these settings the power at 532 nm was 48.7 mW.  The power at 1064 nm was 1.54 W.  The power was fairly
stable (+/- 0.1 mW) over a 2 hour period.  Longer term monitoring should be done (ideally).
H1 ISC (CDS)
filiberto.clara@LIGO.ORG - posted 09:47, Thursday 01 June 2017 (36585)
Cable for readback signal on ALS X IR Photodiode repaired

WP 6665
FRS 8249
alog 36530

Cable for H1:ALS-X_LASER_IR_DC photodetector read back signal was re-terminated with a right angle BNC. Right angle adapter is no longer needed. Verified read back signal on MEDM screen.

F. Clara, R. McCarthy

H1 PSL (PSL)
corey.gray@LIGO.ORG - posted 09:42, Thursday 01 June 2017 (36584)
Weekly PSL Chiller Reservoir Top-Off

Crystal Chiller:  Topped off with 125mL

Diode Chiller:  Ed mentioned this was flashing red off/on, so it was borderline.  I put in 200mL on Ed's suggestion.

Filters:  White in color & free of debris

This closes FAMIS #6525.

H1 PSL
peter.king@LIGO.ORG - posted 08:48, Thursday 01 June 2017 (36583)
FSS transfer function
I looked at the frequency stabilisation servo this morning.  As it was the UGF was a bit low
at ~185 kHz with a phase margin of ~35 deg (CG=16, FG=9).  Raising CG to 22 increased the phase
margin to ~48 deg but didn't quite put us where we would like to be.  Dropping CG to 19 put the
operating point to where we would like it to be.

   I took the opportunity to touch up the alignment into the reference cavity.  The transmission
signal went from ~2.7 to ~3.5.  I restored CG to 16.
Images attached to this report
H1 General
edmond.merilh@LIGO.ORG - posted 08:18, Thursday 01 June 2017 (36581)
Shift Transition - Day

TITLE: 06/01 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Engineering
OUTGOING OPERATOR: N/A
CURRENT ENVIRONMENT:

Winds calm, primary and secondary uSeiem are calm
QUICK SUMMARY: ops lazy script isn't doing transition (-t).

 
 
 
LHO General
patrick.thomas@LIGO.ORG - posted 21:43, Wednesday 31 May 2017 (36580)
Ops Eve Shift Summary
TITLE: 05/31 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: None
LOG:

23:21 UTC Dave offloading minute trends onto h1fw1
23:39 UTC Jenne using PZTs to coalign green onto IR at DC_READOUT
23:45 UTC Jenne done
00:19 UTC Starting initial alignment
00:46 UTC ALS X green falling off in initial alignment. Adjusting PR3 helped bring it back and increased the COMM beatnote. Moving BS to improve AS AIR flashes also helped.
01:15 UTC Initial alignment done
Could not lock past DRMI
02:17 UTC Commissioners have left
02:17 UTC Kyle to mid Y
02:34 UTC Kyle back
02:59 UTC Kyle leaving for the night

Leaving the IFO at DOWN.
H1 ISC
jenne.driggers@LIGO.ORG - posted 19:08, Wednesday 31 May 2017 (36578)
SRM ASC new input matrix at high power, reset green alignment setpoints

[Kiwamu, Jenne, Vaishali]

Today we reset the green initial alignment setpoints (input laser pointing and ITM camera centroids) to match the SOFT offsets that we like at high power.  Hopefully this makes locking more smooth, since the SOFT loops won't have to work very hard anymore.

We also chose new input matrix elements for the SRM ASC at high power.  Kiwamu noted that AS36B was more responsive than AS36A (which is what we had been using), so we use mostly B with a little bit of A to get the total error point to be zero at the optimal SRM pointing. This is now in the guardian, although we haven't been able to relock to try running through the SRM_ASC_High_Power state.  It should be fine though.

We lost lock at basically NomLowNoise when we closed the beam diverters.  I'm not sure it was them - I think it was just time-coincident with a CSOFT pitch oscillation at 2.75Hz that came from my increase of the CSOFT Pit gain from 0.6 to 0.8 in an effort to squash the dP/dTheta instability.  I think we need to get locked and measure the CSOFT loop to see if we can increase the gain at all, although it looks like the more promising plan might be to re-engage the ISS 3rd loop.  We'll think on this more tomorrow.

Right now we're having trouble holding the IFO on ALS.  Both Ed and Patrick noticed that the FSS is oscillating pretty regularly, and they're concerned that it's what is causing our locklosses.  Peter and Jason, can you please take a look at the FSS in the morning?

LHO VE
chandra.romel@LIGO.ORG - posted 16:24, Wednesday 31 May 2017 - last comment - 19:57, Wednesday 31 May 2017(36576)
CP3 clog gone....maybe

We have reason to believe that CP3 is fixed and the ice blockage is gone. However, there was an auto overfill today at 11 am which may be skewing the reading, so we will let things settle overnight. Reservoir level reading is 100% on Beckhoff (software limit) and 120% on Magnehelic. Today we found the sensing line valves open to transducer, along with the valve that isolates them from each other, so we have been flowing much of the GN2 straight out the exhaust. Kyle checked these valves last night and thought the isolation valve was closed, but turns out it was just sticky and actually open.

We connected GN2 to CP4 sensing line, and will leave it connected for days vs. hours this time (readout on MEDM falsely shows 100% full). The flow is essentially zero right now, but set to 2 LPM in case it does open up. Isolation valve between two sensing lines is closed.

We are leaving CP3 LLCV in manual mode tonight.

 

Comments related to this report
kyle.ryan@LIGO.ORG - 19:57, Wednesday 31 May 2017 (36579)
1915 - 1930 hrs. local 

I had to convince myself (again) that we don't still have residual LN2 from today's overfill trapped between the current/former sensing line blockage and the, now closed, exhaust path.  Since the valve separating the exhaust sensing line from the bottom draw sensing line (a.k.a. the low pressure line vs. high pressure line) was open during today's overfill and the fact that the pump's exhaust line is at the highest elevation, it is conceivable that the sensing lines are filled with LN2 during an overfill.  If so, then following an overfill, if this valve gets closed, as happened today, LN2 could be trapped with no exhaust path as it converts to GN2. The resulting pressure would "test" the bi-braze joint and blockage.  There could be LN2 still in the portion of the sensing line within the vacuum vessel even though the external-to-vacuum portion of the line is "warm" and having no frost.  So, I (again) opened this valve to provide a path to atmosphere but observed no evidence that there was any pressure release or flow (I really do need to make some friends and to "get a life").  For CP4 the 1/4 polyflo tubing and acrylic rotometer effectively provide pressure relief as they would split long before the bi-braze joint.  For CP3, I left the magnahelic differential pressure gauge valved in and it should fail in such a way as to relieve any extreme pressure long before the bi-braze joint.  

0800 - Leaving site (again)
LHO General
patrick.thomas@LIGO.ORG - posted 16:16, Wednesday 31 May 2017 (36575)
Ops Eve Shift Transition
TITLE: 05/31 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
OUTGOING OPERATOR: Ed
CURRENT ENVIRONMENT:
    Wind: 11mph Gusts, 9mph 5min avg
    Primary useism: 0.04 μm/s
    Secondary useism: 0.07 μm/s 
QUICK SUMMARY:

Jenne, Kiwamu, Vaishali, Jeff K, relocking.
H1 General
edmond.merilh@LIGO.ORG - posted 15:55, Wednesday 31 May 2017 (36411)
Shift Activity

TITLE: 05/31 Day Shift: 15:00-23:00 UTC (08:00-16:00 PST), all times posted in UTC
STATE of H1: Planned Engineering
INCOMING OPERATOR: Patrick
SHIFT SUMMARY:
LOG:

 

H1 ISC (ISC)
peter.king@LIGO.ORG - posted 15:36, Wednesday 31 May 2017 (36574)
ALS EndX laser biopsy
Performed a quick check of the ALS laser that was removed from EndX yesterday, InnoLight Prometheus S/N 2011B.
The datasheet for this laser is here.  The following settings
were as I found the laser:
  diode current                    1.832 A
  laser crystal temperature        29.02 degC
  doubling crystal temperature     33.41 degC
  diode 1 temperature              20.99 degC
  diode 2 temperature              20.30 degC
The output power at 532 nm was 47.4 mW as measured by a Thorlabs S140C power meter. The output power at 1064 nm was 1.53 W as measured by a Gentec TPM300 power meter. Initially the power at 532 nm seemed reasonably stable. Then I observed it climb from 47.4 mW to ~60 mW and back down a couple of times. During these episodes the 1064 nm power remained stable. The frequency doubling crystal TEC error signal varied from 1 mV to 2.2 mV. Which corresponds to a temperature change of 1.2 mV / (10 V/degC) = 0.12E-3 degC. The change in wavelength with respect to temperature is ~0.03 nm/degC. However just because the wavelength changes doesn't necessarily mean the output power changes, that depends on the resonator finesse. I then set the laser settings to those listed in the datasheet, namely
  diode current                     1.750 A
  laser crystal temperature         24.00 degC
  doubling crystal temperature      33.20 degC
  diode 1 temperature               20.99 degC
  diode 2 temperature               20.31 degC
At these settings the output power at 1064 nm was 1.44 W. Initially the output power at 532 nm was 41.4 mW but was seen to vary as high as ~63 mW. Again no temperature or diode power related signals appeared to vary in sync with the observed power changes. Perhaps of note is the thermistor reference voltage(s) were measured to be 6.64 V and 6.58 V, instead of 6.85 V for both the frequency doubling crystal and diode 2 respectively. Without knowing the circuitry for the thermistor, I don't know if this is significant or not.
H1 PSL
jenne.driggers@LIGO.ORG - posted 14:26, Wednesday 31 May 2017 (36573)
Recalibrated PSL rotation stage

Everyone in the control room was sad that requesting 30W of injected power was only getting us 27W.  So, I ran the calibration scripts from alog 30479.  Now 2W is 2W, 10W is 9.9W, and 30W is 29.8W.  Much better.

Attached screenshots are the old calibration and the new calibration values in the calibration screen.  Jeff has made these values monitored in the SDF (were un-mon before).

Images attached to this report
H1 PSL
edmond.merilh@LIGO.ORG - posted 13:15, Wednesday 31 May 2017 - last comment - 14:14, Wednesday 31 May 2017(36570)
PSL Weekly Report - 10 Day Trends FAMIS #6150
Images attached to this report
Comments related to this report
jason.oberling@LIGO.ORG - 14:14, Wednesday 31 May 2017 (36572)

Everything looks normal with these trends.

H1 CDS (IOO, ISC)
jeffrey.kissel@LIGO.ORG - posted 12:46, Wednesday 31 May 2017 - last comment - 12:50, Wednesday 31 May 2017(36568)
Drift in 9 MHz EOM Driver's Beckhoff Readback
J. Kissel, D. Sigg

Investigating the last corner station Beckhoff error, regarding the 9 MHz EOM driver offset. There are complaints that the read back (H1:LSC-MOD_RF9_AM_RFOUT and H1:LSC-MOD_RF9_AM_RFSETMON) is out of range at ~18.6 [dB], where the request (H1:LSC-MOD_RF9_AM_RFSET) is 16.8 [dB].  Unclear what the tolerance is; appears to be internally set and not broadcast over EPICs. Side note: leading up to and during O2, when IFO is down/acquiring, it's reduced to 10.8 in NLN.

The offset was set to 16.8 dB on Feb 23 2016 (see LHO aLOG 25687), to balance the RF power of the driver, and its readback has been slowly drifting *up* from there since.
Looking back further, we see similar upward drift during O1, even though the offset's request was different.
45 MHz Beckhoff readbacks are stable.

Fast ADC version of the control voltage (H1:LSC-MOD_RF9_AM_CTRL_OUT16) doesn't show the drift. Also the values don't agree. 

Tolerance increased LHO aLOG 30406 (perhaps unbenowst to the increaser) to accommodate the drift.

Chassis assembly E1400445
    Controller Circuit D0900761.

These channels are all readout by a single 4 channel ADC as the readback: ecatc6 Middle Rail 10 is the module (from D1300745). Maybe internal voltage reference drift?

Recommendations:
- either check the cabling at the ADC
- measure the input to the ADC to confirm the expected voltages
- replace the ADC.
Images attached to this report
Comments related to this report
jeffrey.kissel@LIGO.ORG - 12:50, Wednesday 31 May 2017 (36569)
Opened FRS ticket 8250 with regards to suspicious Beckhoff readback for the 9 MHz EOM driver.
H1 SEI
jim.warner@LIGO.ORG - posted 12:05, Wednesday 31 May 2017 - last comment - 18:10, Wednesday 31 May 2017(36565)
Z tilt decoupling on BSC ISI's

Last week we took advantage of the down time to do Z diagonalization measurements on the BSC ISI's, as Jeff outlined in his alog 36360. I used the data we got to calculate and install coefficients on all of the chambers that needed decoupling. The first five plots  are the closeout Z to X/Y transfer functions comparing the before and after results showing the reduced coupling via tilt from Z drive to X/Y motion seen by the St1 T240s. For these plots, blue is always before, red is the after measurement. I forgot to include Y units but they are in nm/s / nm*rthz because I didn't convert the T240 signal to displacement.

Yesterday I looked at repeating this on the output HAM's, I was just efficient enough to get HAM4 mostly done, but I need more time finish HAMs 2,3,5,6. The last attached plot is the Z to X/Y plots before and after for HAM4. The magnitude plots are in nm / nm*rthz. I also got data for HAM4 Y to RX, but it looks like the ISI is good enough in that DOF. HAM5 was similarly clean for Z to RX/RY, and I have a coefficient calculated for HAM6 Z to RX, but I would like to do a measurement after installing the cpsalign elements before I make a permanent change.

Images attached to this report
Comments related to this report
jim.warner@LIGO.ORG - 12:18, Wednesday 31 May 2017 (36567)

The measurements for the HAMs are essentially the same as the BSCs, driving at the inputs to isolation banks while the ISI is isolated with high blends (750mhz for the HAMs) with sensor correction off. Drives are usually 1-5e7 in awggui, for as long as you have patience for.

jeffrey.kissel@LIGO.ORG - 18:10, Wednesday 31 May 2017 (36577)
For the record, and to be explicit for future reference, here're the BSC-ISI ST1 tilt decoupling matrix elements (H1:ISI-${CHAMBER}_ST1_CPSALIGN_${M}_${N}) that Jim has now installed. One reads the matrix as "The corrected RX and RY CPS signals used in the isolation loops contain small portions of X, Y, and Z signals."

ETMX                  misaligned
               X           Y          Z
 a
 l    X        1           0          0
 i    Y        0           1          0
 g    Z        0           0          1
 n    RX    -0.0030    -0.0020     +0.0060
 e    RY    +0.0013    +0.0001     -0.0025
 d    RZ       0           0          0   

ETMY                  misaligned
               X           Y          Z
 a
 l    X        1           0          0
 i    Y        0           1          0
 g    Z        0           0          1
 n    RX     +0.0010    -0.0010       0
 e    RY     +0.0005    +0.00075      0
 d    RZ       0           0          0   

ITMX                  misaligned
               X           Y          Z
 a
 l    X        1           0          0
 i    Y        0           1          0
 g    Z        0           0          1
 n    RX     +0.0015    -0.0025       0
 e    RY     +0.0015    +0.0015    +0.0025
 d    RZ       0           0          0  

ITMY                  misaligned
               X           Y          Z
 a
 l    X        1           0          0
 i    Y        0           1          0
 g    Z        0           0          1
 n    RX     +0.0015    -0.0007    -0.0057
 e    RY     +0.00075   +0.0005    +0.0030
 d    RZ       0           0          0  

BS                  misaligned
               X           Y          Z
 a
 l    X        1           0          0
 i    Y        0           1          0
 g    Z        0           0          1
 n    RX     -0.0001    -0.0007    -0.0035
 e    RY     +0.00075      0       +0.0025
 d    RZ       0           0          0  
H1 ISC (CDS, DetChar, OpsInfo)
jeffrey.kissel@LIGO.ORG - posted 17:17, Tuesday 30 May 2017 - last comment - 13:20, Wednesday 31 May 2017(36538)
ALS Y WFS A Demod Local Oscillator Power Surpasses Threshold; Throws Error; Threshold Increased
S. Dwyer, J. Kissel

We found that the Beckhoff error handling system was reporting an intermittent error on ALS Y WFS A Demod Local Oscillator (LO) Power (H1:ALS-Y_WFS_A_DEMOD_LOMON) having surpassed its threshold (H1:ALS-Y_WFS_A_DEMOD_LONOM). 

Trending reveals that
 (a) The error bit has been green since the Beckhoff ADC was replace on Sept 22nd 2016 (see LHO aLOG 29848) 
 (b) the LO's power has been slowly increasing over time, and was now on the hairy edge of the threshold.

After consulting Sheila, she suggests "it's probably fine," so I increased the threshold from 21 [dBm?] to 22.5 [dBm], and accepted the new threshold in both safe and OBSERVE.snaps in the SDF system. (I'm not confident that this monitor is actually calibrated into physical units, but 21 [dBm] doesn't sound crazy so I put confidence in the designer of the system to have done so.)

Hopefully this doesn't turn out to be a canary for the demodulator like the diode laser power was to the now replaced ALSX laser...

Images attached to this report
Comments related to this report
jeffrey.kissel@LIGO.ORG - 11:37, Wednesday 31 May 2017 (36561)
Opened FRS Ticket 8248 regarding missing 6 dB attenuator on the ALS COMM VCO path.
jeffrey.kissel@LIGO.ORG - 17:55, Tuesday 30 May 2017 (36540)CDS, DetChar, ISC
Other thresholds updated / cleaned up:

H1:ALS-C_COMM_A_DEMOD_LONOM increased from 12 to 19 [dBm?]
   The monitor channel H1:ALS-C_COMM_A_DEMOD_LOMON increase from about 12.4 to 18.3 [dBm?] on March 01 2017 ~23:00 UTC (mid-afternoon local time). I could find an associated aLOG about this.

H1:ISC-RF_C_AMP137M_OUTPUTNOM increased from 20 to 21.5 [dBm?]
   The monitor channel H1:ISC-RF_C_AMP137M_OUTPUTMON has been as high as 22 [dBm?] between Feb 7 and Mar 23rd, but then was brought back to ~21 with some small steps between then and now. No aLOGs about this one either.

All of these monitor channel changes were through the course of the observing run, so we presume that this is the new normal. New thresholds have been accepted into the SDF system.
Images attached to this comment
daniel.sigg@LIGO.ORG - 21:02, Tuesday 30 May 2017 (36548)

A nominal LO for a length sensor is around ~10-13 dBm. For a WFS the signal level is divided between the 4 segments. In software, the readbacks are added back together, so the LO sum should be similar in value. For the demodulators the RF power is measured after an internal 10-11 dB amplifier. So, a normal readback will be around 21-24 dBm for the LSC and the ASC sum. There is no amplifier for the phase-frequency discriminators, so their readbacks will be between 10-13 dBm.

For a distribution amplifier the power is measured before the 8-way splitter and is nominally around 22 dBm.

The ALS-C_COMM demod is driven by the COMM VCO. Alog 34512 describes a measurement involving the COMM VCO. It looks like a 6dB attenuator was left out when the changes were reverted. This should be fixed.

Not sure what happened on Feb 7, but on March 23 the harmonics oscillator was swapped which required a readjustment of some of the RF attenuators. Looks like H1:ISC-RF_C_AMP137M_OUTPUTNOM was effectively reduced by 1dB, see alog 35051. This is fine.

daniel.sigg@LIGO.ORG - 13:20, Wednesday 31 May 2017 (36571)

Checking the ALS WFS RF readbacks:

  • X channels seem to be fine
  • In Y only ALS_Y_WFS_A shows a drift
  • Among the 4 segments, only chn 3 and 4 show the drift

This indicates that the EL3104 module L7 in EtherCAT end 3 (D1400175-v2) of EY is broken too.

Images attached to this comment
LHO VE (CDS)
filiberto.clara@LIGO.ORG - posted 16:40, Wednesday 24 May 2017 - last comment - 10:56, Thursday 01 June 2017(36396)
BRS vacuum pressure read back signals - End Stations

WP 6652
ERC 170062

The BRS ion pump read back signals are now tied into the vacuum rack. Field cabling from each controller was pulled to connector header H (Pins 37-40) inside the vacuum rack. The Vacuum Controls Chassis was modified to add the new read back signals to terminal 15. Channel 1 is the voltage read back and channel 2 is the pressure read back.

Controllers for the BRS ion pumps are not the same.

End Y - Gamma SPCe controller
End X - MiniVAC Controller

F. Clara, G. Moreno, R. McCarthy, P. Thomas

Comments related to this report
gerardo.moreno@LIGO.ORG - 10:56, Thursday 01 June 2017 (36586)VE

(Krishna V., Gerardo M.)
Information for both systems:
BRS-Y
- ion pump is a TiTan 10SW from Gamma Vacuum (PN:10SWCV2HSCNN).
- the controller is a SPCe from Gamma Vacuum (PN:SPC1PS1U1ESNA).
- for the high voltage connection the system uses a SAFECONN type of cable/connectors.
- HV polarity is + (positive)

BRS-X
- ion pump is an old Varian 10 l/s pump.
- the controller is a MiniVac from Varian (PN:EX9290191)
- for the high voltage connection the system uses a FISHER type of cable/connectors.
- HV polarity is - (negative)

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