TEL-01 shipped ha_dsmr and mqtt_p1. Neither fits the installed meter - a
HomeWizard P1 publishing one signed figure, where ha_dsmr requires two unsigned
registers and refuses negatives. So sensor.p1_sample_age_s could not be produced
here at all.
ha_signed is a subclass of HaDsmrSource overriding only _wanted() and build(),
so ingest timestamping, staleness, the clock-recomputed age, plausibility bounds
and unavailable-is-never-zero are inherited by construction rather than copied.
A reviewer traced every inherited member and confirmed nothing in the base
assumes two entities.
122 -> 179 checks. Sign convention asserted against real captures in
sim/scenarios/: -5710 W at 13:46 local under full sun, +775 W at midnight,
verified to the timestamp by two people independently.
WHAT THIS DOES NOT DO, documented in DOCS.md, the docstring and the CHANGELOG
rather than discovered later: the age it publishes measures time since the VALUE
CHANGED, not since the meter reported. Home Assistant exposes no arrival signal
for a repeated reading - proven on the rig against a frozen meter (no
state_changed, last_reported advancing on neither serialiser, state_reported
rejected outright) and confirmed independently against the live house, where ten
repeated values all left last_reported frozen. So this entity must NOT yet be
thresholded by the firmware watchdog. ha_dsmr has the same blind spot and
escapes only statistically, because a DSMR telegram moves several entities.
The fix is to read the meter's own API, where every response is an arrival.
That is TEL-05, and it is FW-01's real gate.
Two equivalent mutants are known and recorded: the per-phase split, documented
at the site, and the incomplete-phase-set guard, which is cosmetic - both paths
return False, one via an extra log line.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
