Keita, Sheila, Kiwamu

We have made a few changes to the way the guardian manages the ISS second and third loops that we think will allow us to use the third loop and not have locklosses when DC coupling the third loop

• We have changed IMC_LOCK so that it now manages the input and output from the ISS_THIRDLOOP_SERVO filter, so we can avoid confusion about when the third loop will be on or off.
• Before the second loop is DC coupled, the third loop gain is set to zero.
• We made the code that engages the third loop into a function that is now called twice, in the states POWER_UP_TR_CLOSED which is requested by ISC_LOCK in INCREASE_POWER and once in NOMINAL_TR_CLOSED which is requested in NOISE_TUNNINGS
• We increased the ramp time used for engaging the third loop, from 3 second to 10.  We hope this will decrease the transient that sometimes unlocks the IFO when the third loop is engaged with DC coupling on.

J. Kissel

In order to facilitate drag-and-drop into dataviewer, I've edited all SUS type's coil driver monitor MEDM overview screens to watch the OUT16 EPICs output instead of the OUTMONs. 

The following screens have been committed to the userapps repo:
/opt/rtcds/userapps/release/sus/common/medm/
    bsfm/SUS_CUST_BSFM_MONITOR_OVERVIEW.adl
    hxts/SUS_CUST_HXTS_MONITOR_OVERVIEW.adl
    omcs/SUS_CUST_OMCS_MONITOR_OVERVIEW.adl
    quad/SUS_CUST_QUAD_MONITOR_OVERVIEW.adl
    tmts/SUS_CUST_TMTS_MONITOR_OVERVIEW.adl

TITLE: 06/28 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 66Mpc
INCOMING OPERATOR: Cheryl
SHIFT SUMMARY:

Quiet shift. H1 locked for 11+hrs @ 68Mpc
LOG:

It seems that Seismon hasn't updated since the EQ near Indonesia yesterday

H1 locked and observing for 7hr20min @ 68Mpc. There were a couple of glitches and no sign of ASC pitch instability. Environment is calm and DARM looks good.

Everything looks normal. Evidence of current adjustments made to the HPO Diodes last week are the only thing of notice.

TITLE: 06/28 Owl Shift: 07:00-15:00 UTC (00:00-08:00 PST), all times posted in UTC
STATE of H1: Observing at 68Mpc
OUTGOING OPERATOR: Travis
CURRENT ENVIRONMENT:
    Wind: 16mph Gusts, 12mph 5min avg
    Primary useism: 0.04 μm/s
    Secondary useism: 0.09 μm/s
QUICK SUMMARY:

TITLE: 06/28 Eve Shift: 23:00-07:00 UTC (16:00-00:00 PST), all times posted in UTC
STATE of H1: Observing at 68Mpc
INCOMING OPERATOR: Ed
SHIFT SUMMARY:  Some trouble getting to NLN during the first half of the shift until Keita disabled the ISS 3rd loop.  Since then, we have been in Observing for 3 hours.  No other issues.
LOG:  See previous aLogs.

The annulus pressure in HAM 11,12 (diagonal volume) is rising and causing the both AIPs to fall out of range. Both AIPs were replaced in May 2016. Today I leak checked all door and flange outer o-rings on HAM 11, 12, and also AIP conflat flanges. Found e-5 Torr-L/s of He range leak at bottom of HAM 11 south door and e-7 Torr-L/s of He range leak on HAM 12 south door. Kyle tightened bolts but flanges were already metal on metal. Suspect there is an imperfection on outer o-ring seal. Will address next time we have the opportunity to vent (or decommission) the diagonal volume. 

FRS 8411

Finally back to NLN and Observing.

After retuning the SRCL FF yesterday (37150), Travis eventually got the interferometer locked after some problems with a windstorm, the CARM offset reduction, and eventually the ISS second loop.  That lock in the first hour or so of Ed's shift had a better range than we have had in quite a while. 

The time for the better spectrum below is June 27th 2017 7:39:16 UTC, while the "before" time is June 26th 2017 19:25:21 UTC. It would be interesting to take a look at a long bruco report for the after time. The jitter is a little lower in the after time, which is probably just due to an alignment drift. The range at this time is the best we have had in a long time, as shown by the 90 day trend in the second screenshot.

Sheila Kiwamu Patrick

We looked at a couple of the locklosses that people had from NOISE_TUNINGS last night.  We found that the problem is when the ISS second loop becomes DC coupled it saturated.  The attached screen shot shows some of the symptoms, where MC2 trans power is ramping up right before the lockloss, the IMC guardian changes state to turn off the ISS, the AOM driver mon and ISS second loop outputs have dramatic changes in the seconds before the lockloss. 

I followed the instructions by Jeff K and D Sigg in alog 31942 to reset the ISS diffracted power. (H1:PSL-ISS_REFSIGNAL and H1:PSL-ISS_SECONDLOOP_AC_COUPLING_OFFSET)

I am not sure if turning on the ISS 3rd loop (done to help avoid CSOFT Pitch problems over the weeked) contributed to this being a problem last night.