hugh.radkins@LIGO.ORG - posted 11:56, Wednesday 09 November 2016 - last comment - 01:02, Thursday 10 November 2016(31366)
ETMY ISI Blend did not switch
Sheila reported that Nutsinee switched the SEI_CONFs to BLEND_45mHz_SC_useism last night but looking this morning I see that it did not switch the Blend on ETMY. I manually switched the (X & Y dof) Blends only; the Sensor Correction did switch to not use the BRS. Otherwise all switching worked with Sensor Correction for all Test Masses and no BRS in use at the Ends.
by the way, I noticed this issue because I saw the SDF differences at the end stations were not the same. Since this is a guardian controlled feature, it might be argued that it would be Not_Monitored. Were that the case...
In case you are wondering what difference this can make...
The attached asd shows the ETMs 12 and 6 hours ago. 12 hours ago (ref traces) the ETMY was in 250mHz blends while the ETMX was in the 45mHz blend. 6 hours ago was after the ETMY was actually switched to 45mHz blends.
The thick green and brownish curves become much more like the others after the blend switching and moving the blend gain peaking away from the secondary microseismic peak.
The second attachment are trends of theX & Y ARM SUSPOINT Motions based on the ISI's onboard GS13s and the ETMY and ITMY SWSTAT showing when the ITMY blend switched but the ETMY did not and then this morning when the ETMY switched to the same blend as the ITMY. When the two ISIs are in different blends, the motion is clearly larger although based on these trends. Based on the XARM Motion though, not clearly a better blend overall.
ETMY_ST1_CONF wasn't switching properly because I had found an issue with the guardian when trying to write some different configurations. I forgot to revert the code to a properly working state. Sorry. I've fixed the configuration, and tested that it works on ETMY.