[Corey, Sheila, Dave, Jenne]

With the ITM ESD high voltage interlock being used instead for HAM6 high voltage things, we cannot use the ITMs for the ESD transition at the end of the locking sequence.  We are trying to instead use ETMY. 

• Sheila had started work on modifying our usual guardian states, to allow us to use the L3 on ETMY.  That was in progress, when we decided to try the prewritten (but not tested in while) 'lownoise esd etmy' states.
• We tried using the 'lownoise esd etmy' state, but lost lock when it was doing the L3 Lock L 5 second ramp over to using ETMY.
  • Yesterday's lockloss (at least the one around 27 Dec 2024 02:03:00 UTC) was, as Corey said, successful getting off of ETMX, and then failed at swapping back to the low voltage version of ETMX.
  • Today's lockloss had a ringup of about 161 Hz.
• Richard called to check in, and said that it shouldn't be too hard to tee off (or something) that interlock cable, so that it can be used for both ITM ESDs and also the HAM6 high voltages.  Richard is planning to talk to Fil about the feasibility of this.
• Since our current plan is to see if we can go back to our nominal locking sequence, I have copied over Sheila's temporary guardian changes (attached here, also), and done an SVN revert to the version of ISC_LOCK.py that RyanS had checked in just before the winter holidays.  The only diffs between that version and the version in the userapps directory were related to today's temporary changes.  Corey has reloaded the guardian.
• Richard checked with Fil, and Fil is on the way to make the change, so we can go back to using our usual locking sequence.