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Author SHA1 Message Date
adminandClaude Opus 5 83911ed637 SAFETY-20: measure the freeze rail against the reachable ceiling, not max_w
checks / unit (pull_request) Successful in 3m37s
SAFETY-18's conjunction needs `abs(commanded_w) >= 0.95 * max_w`, but the
emitted command is clipped to the setpoint device's own [dev_min, dev_max]
range as well as to max_w - in clamp_to_rating()'s second stage and again as
the arbiter's `device` P_SAFETY limit claim. Measured on the shipped predicate
at the ticket's numbers, max_w 5000 on a +-4700 W inverter:

    looks_frozen(unchanged_s=3600, commanded_w=4700, max_w=5000)  ->  False

The command is pinned at the hardware's rail, the meter has been frozen for an
hour, and term 2 is unsatisfiable by construction because 4700 < 4750. Any
device rating at or below 0.95 * max_w disarms the conjunction outright, and
the status page then printed `armed (... command is over 4750 W)` - a guard
that cannot fire, advertising that it can, which is the failure SAFETY-15,
SAFETY-19 and validate.py rule 5 all exist to prevent.

The rail is now measured against min(max_w, |dev_min|, |dev_max|), through a
new `rail_ceiling_w()` threaded into looks_frozen(), FreezeWatchdog.evaluate()
and both call sites in main.py. An unread rating leaves the old behaviour
exactly, and correctly: hass.limits() returns None whenever ESPHome is not up,
and on that path no device clamp is applied either, so max_w really is the
ceiling. A rating larger than max_w cannot raise the rail - this is a min(),
not a swap.

THE DELIBERATE CHOICE, since SAFETY-03 has landed. The arithmetic was kept
rather than substituting Decision.i_clamped / Decision.clamped. i_clamped is
the integrator bound (control.py:208, `bounded != i_w`), not "the command is
at the device rating", and `clamped` is the max_w output bound, unreachable on
a default install - neither is the device rail. More decisively, both answer
"did the LOOP ask for more than a bound", while the rail term asks "is the
command standing at the ceiling", and those coincide only when the loop is the
claimer that won. A maintenance SET or a peak-guard floor reaches the ceiling
through arbiter LIMIT claims with no clamp engaging at all, so a boolean rail
would go False exactly during a maintenance phase running against a frozen
meter - which freeze.py's own docstring names as the same fault with a worse
actuator behind it. The predicate is also public with two call sites that pass
DIFFERENT command values (self.target, and `standing` = last_write); a
per-cycle boolean cannot be passed per call site, so substituting it would
have silently decided the pre-clamp-versus-wire question that PM recorded as
still open. AC 1 governs, and it is satisfied literally.

The smaller of the two device bounds, not a per-sign pair. A per-sign rail is
tighter and is not wrong, but it is two rails needing two coverage verdicts on
a status row that carries one number, and the only configuration that
distinguishes them is refused at startup anyway. The symmetric ceiling can only
lower the rail, which widens term 2 rather than disarming it; term 1 carries
the whole no-false-positive argument and is untouched.

A ceiling of 0 W is NOT COVERED, not "armed at 0 W". A device that can command
nothing in one direction would make `abs(command) >= 0` true of every command
including a parked one - term 2 degenerately TRUE, collapsing the conjunction
into the bare unchanged_s > N threshold TEL-05 refused for false-tripping at
this controller's own operating point. rail_unreachable() returns the reason,
looks_frozen() stays silent, and the page uses the NOT COVERED row the
unsupported-transport case already has - a second reason to use that surface,
not a new mechanism.

AC 4, decided rather than assumed: NO NEW validate.py RULE. The configuration
is max_w above the device rating, which rule 2 (CFG-01) already refuses on the
identical predicate, re-run by run_control() once the real rating is known:

    validate_startup_config({... max_w: 5000}, -4700, 4700)
      -> ['max_w is 5000 W but number.sp accepts at most 4700 W - THE DEVICE
          WINS ...']

A rail-specific rule would fire on a strict subset of that (0.95 * max_w >
dev_max implies max_w > dev_max) and could never be the rule that stopped a
start. The residue is the state where hass.limits() answered (None, None) -
ESPHome not up at boot, range checks skipped rather than guessed at, rating
never re-read - and there is nothing to refuse there by construction, which is
why the answer is a runtime row. Recorded in validate.py's "deliberately not
refused" list and pinned by four checks in test_validate.py, so the decision's
premise goes red if rule 2 is ever softened back to a warning.

HOW REACHABLE THIS IS, stated rather than glossed. Because rule 2 refuses the
configuration whenever the rating is known, min(max_w, dev_max) IS max_w on
every install that reaches the control loop with a rating it could read, and
this change is arithmetically dead there. That is clamp.py's argument for its
own second stage word for word: the case where it bites is the case where the
startup gate did not run or no longer holds, and a guard that quietly assumes
the gate ran is a guard that reports armed in exactly the state it cannot fire
in.

Verified by breaking it, per this project's rule. Reverting rail_w() to bare
max_w fails nine checks; deleting the NOT COVERED handling fails five. The one
that mattered: shipping the corrected predicate while NOT passing the rating
from check_meter_frozen() left the entire suite green, because nothing graded
the caller - so test_freeze.py part 5b now drives the real cycle() on a +-4700 W
device and asserts on the notification that leaves the process, and the
unwiring mutation fails three checks there. The peak-guard call site's wiring
is still ungraded (behind p1_enabled, needs a fed averager for `frozen` to have
any observable consequence) and that gap is named in the file rather than
implied.

Full suite: 15/15 in goodwe-addon-ci.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-01 02:14:07 +02:00
glenn schrooyenandClaude Opus 5 0ba3a200fe SAFETY-18: verify on the real rig, and record what it showed
AC3 says "verified on the rig". The previous commit drove hwsim in-process
because `riglock status` reported UNKNOWN - which is the tool declining to
observe, not an observation. riglock shells out to the local docker CLI; on a
Windows host without DOCKER_HOST that resolves to a Docker Desktop npipe which
is not running, and the result is indistinguishable from a genuinely absent rig.
The rig was up the whole time. With DOCKER_HOST=ssh://homelab@192.168.2.147 it
reads FREE.

Re-run under sim/riglock.py against the real goodwe-sim compose project, with
the shipped modules staged into goodwe-sim-plant so they poll that container's
own hwsim while plantsim drives it. Both phases passed, lock released cleanly.

The rig produced a result the in-process stub could not, and it strengthens the
design rather than merely confirming it: in the NEGATIVE twin - +8000 W of house
load, healthy meter, correctly railed command - `active_power_w` did not move at
all, sitting at exactly 10130.0 W for 26 consecutive polls. The only thing
keeping `unchanged_s` at 0.0 s was the kWh registers advancing.

So the register terms in measurement_fingerprint() are not belt-and-braces for
this detector, they ARE the negative case: fingerprinted on the power figure
alone it would have raised a false alarm on a healthy meter under a real load,
which is precisely how a safety guard gets switched off. Recorded in freeze.py
so nobody simplifies the fingerprint without meeting that run first.

No behaviour change - documentation and the harness note only.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015VXjA3LWccN1rJsk3okyPC
2026-08-30 02:49:55 +02:00
glenn schrooyenandClaude Opus 5 7aa1bd052e SAFETY-18: a meter frozen at a wrong-but-fresh value now raises an alarm
A meter that answers 200 OK with a stale document forever is ARRIVING on every
poll, so every freshness mechanism in the stack reads it as healthy while the
loop integrates a constant error and rails: 360/135/75 s at the live install's
max_w: 5000 for a meter frozen at 350/1000/>=3000 W. Fifteen minutes of a 5 kW
unattended import sets the month's billed capaciteitstarief peak.

The detector is a conjunction, not the bare unchanged_s threshold TEL-05
measured and rejected:

    unchanged_s >= meter_freeze_s   AND   |command| within 5 % of max_w

Both terms already existed and were already on the status page, and they fail
for independent reasons: at the converged point the command is nowhere near the
rail, and at the rail against a real load the kWh registers move in seconds. At
the shipped 300 s the relation is structural rather than a margin - the slowest
a healthy 1 Wh register can tick and still look unchanged is 12 W, which is
inside the 15 W deadband, so the command there is parked at 0 W.

Notification only, deliberately: an HA persistent notification with a fixed
notification_id, an ERROR log line, a UI event and a red status row. No claim,
no latch, no 0 W. A false trip parks the battery; a false notification costs an
alert. Only meter_source: homewizard_local is covered - the status page says
NOT COVERED elsewhere rather than pretending the guard is armed.

DOCS.md states the capacity-tariff exposure this does NOT close: peak_cap_w caps
maintenance charging and nothing caps the loop. That cap is SAFETY-07.

test_freeze.py grades both directions and was verified by breaking what it
watches (six mutations, all red): silent over the committed 40-minute converged
capture, silent over an hour of TEL-05's low-power case where the rejected bare
threshold is shown to fire, alarming on a genuinely frozen meter driven over
real HTTP through the real HomeWizardLocalSource (the rig's own hwsim freeze
fault when reachable), silent on the same railed command against a meter that is
still moving, and asserting on the service call that leaves Controller.cycle()
rather than on the watchdog's own flag.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015VXjA3LWccN1rJsk3okyPC
2026-08-30 02:39:54 +02:00