Reports until 16:04, Monday 01 December 2025
H1 SUS
jeffrey.kissel@LIGO.ORG - posted 16:04, Monday 01 December 2025 (88288)
h1susey DAC Upgrade: SUS Recovery Complete
J. Kissel, O. Patane,

After 
- Adding/updating DAC calibration compensation gains
- Updating MEDM macros in order to confirm that DAC drive requests made it all the way out to the analog world on the right channels
- Pausing guardians to make sure they didn't take control when we didn't want them to yet,
- Making sure that all DAC requests were OFF
- Untripping watchdogs and turning ON the MASTER SWITCH
- Turning on small offsets to confirm those channel pathways were straight and linear,
- Turning damping loops, one DOF at a time to confirm function and that they had roughly the right ~few second ring-down time
- Turning on the alignment offsets to confirm that the whole suspensions move
- Restoring all nominal ability for ISC output requests by resuming the guardian and running it from SAFE to ALIGNED a time or two,
- Initiallizing new channels in SDF
- Accepting differences in SDF (almost entirely the turning ON of calibration gains for the stages that were 18-bit DACs)

We turned control over to the operations team with the words "all EY suspensions are confirmed functional and ready to use" at Dec 01 2025 ~15:45 PST (after having started at ~08:30 PST this morning; LHO:88274).