GV-1: which BLEPS per-valve record is the canonical open/closed state for GV1-GV3?

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Question

The 2-BM descriptor models the three gate valves as Vacuum Supply status (vacuum_isolation), and carries them today as bare tags [GV1, GV2, GV3] rather than as PVs. The BLEPS IOC exposes many records per valve:

GVn_CLOSED_LS      GVn_OPENED_LS       GVn_FULLY_CLOSE    GVn_FULLY_OPEN
GVn_CLOSED_SWITCH  GVn_OPENED_SWITCH   GVn_BOTH_SWITCH    GVn_NO_SWITCH
GVn_FAULTED        GVn_OPEN_PERMIT     GVn_CLOSE_PERMIT   GVn_TYPE
GVn_OPEN_COMMAND   GVn_EPICS_OPEN      GVn_EPICS_CLOSE    GVn_BEAM_EXPOSURE

Which of these reflects the physical valve position an operator would act on? Specifically:

1. Is GVn_CLOSED_LS (limit switch) the position of record, or is GVn_FULLY_CLOSE the one to trust?
2. What do GVn_BOTH_SWITCH and GVn_NO_SWITCH indicate? Presumably contradictory or absent switch feedback, but that is a guess.

Context

Read from arcturus on 2026-08-09. 2bmBLEPS:BLEPS:BIV_CLOSED returns GOOD, so the naming convention established in BLEPS-2 (#563) is confirmed working against the deployed IOC. A bare 2bmBLEPS:BLEPS:GV1_CLOSED does not exist; only the suffixed variants above do.

CORA assumes

One per-valve boolean "closed" reading is enough for Supply(kind=Vacuum) status, with the failing valve and its cause named in the Supply transition's reason, per BLEPS-1 (#562).