@@ -75,3 +75,7 @@ Let us run this as a new root cause investigation. Let's make a plan so that we
```
Claude made a plan [bl4b-hs-investigation-plan.md](bl4b-hs-investigation-plan.md). We will start a new session and branch for all this, perhaps more persistent branch for beamline motion investigations.
## Prompt 4
You are working in the tasking project, instrument-motion-investigations branch. Read tasking/tthd-Motion-Failure-Analysis.md. This is the result of a prior investigation regaring the undesirable motion of BL4B:Mot:tthd. Discussing this investigation with Erik, he pointed out an explanation for the non-motion of p_d as part of the interlock system. Indeed it appears as of the BL4B:Mot:shutter:Position PV transitioned from 2 (closed, interlock on) to 0 (moving, interlock on) to 1 (open, interlock off) on 2026-04-10 23:56, exactly when our issues were occuring. BL4B:Mot:tthd was requested to move to -0.8 deg at 23:55, *before* the shutter was closed. Please investigate the interlock indicators that apply and whether the conclusions in the tthd-Motion-Failure-Analysis.md needs yet another revision?
