Review found validate.py:288-289 carrying numbers that appear nowhere
else in the PR's evidence and could not be reproduced: over-absorption
"1233 W at slew 1000 and 1344 W at slew 250 ... 1495 W at 0.6, 961 W at
0.3, ~0 W at 0.2". A grep for 1233/1344/1495 found them ONLY in that
comment - the DECISIONS record, the PR body, test_control.py's audit
table and slew_sim's own output all carried the correct ones.
The measured values, from re-running tools/slew_sim.py on the real plant
model at the stated conditions (max_w 5000, 2 s tick, 51 export steps
1.0-4.2 kW): slew column 958 (slew 1000) and 1081 (slew 250); gain column
987 (0.6), 876 (0.3), 435 (0.2).
⚠️ "~0 W at 0.2" WAS WRONG IN THE UNSAFE DIRECTION. It invited a future
reader to conclude that dropping gain to 0.2 removes over-absorption. It
does not: 435 W remains, which is 44 % of the figure at 0.6, not zero.
The corrected text says so at the line rather than leaving a round number
to be trusted.
The conclusion the paragraph draws is unchanged and still holds on the
measured figures: over-absorption is flat in slew_w and falls in gain, so
`gain` is the constant that would have to move, and SAFETY-39
deliberately does not move it.
No behaviour change; comment only. Full suite: 21 passed, 0 failed.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BwRLw7eKYj2byVdwB6kbjU
`slew_w: 1000` was derived on 2026-08-22 against a clamp of 1500 W, where
"capping how far the loop can jump ahead of the inverter" was true because the
rail itself bounded the excursion. The live install went to max_w 5000 and the
constant did not move, so the loop crosses its whole output range in 10 s
against a plant NOTES.md §5.10 measured at ~18 s. Measured on the owner's system
2026-09-05 11:43-11:46: a 3.4 kW export drove the setpoint 380 -> 5000 W in five
2 s ticks, the battery to -5154 W past a 5000 VA rating, and the grid from
3.4 kW of EXPORT to 2.8 kW of IMPORT. Nothing was broken; the rail moved.
REPRODUCED FIRST, and one half of it is not reproducible at all. On
plantsim.Plant and on an independent in-repo model: the setpoint stepping a full
1000 W per tick to the rail (48 of 51 export steps), and the meter crossing from
export into import. The -5154 W figure is NOT reproducible in either model,
because both clamp the plant at its rating - so the card's AC "battery no longer
exceeds max_w in simulation" is unfalsifiable and was rewritten rather than met.
THE DELIVERABLE IS THE RELATIONSHIP.
SLEW_RAIL_FRAC = LOOP_TICK_S / PLANT_SETTLE_S = 2 s / 18 s = 1/9
slew_w = 0 now means FOLLOW THE RAIL - SLEW_RAIL_FRAC * max_w - exactly as
integrator_max_w = 0 already means follow max_w. It is the shipped default:
222 W at max_w 2000, 556 W at 5000, 1067 W at a ~9600 W two-inverter site.
validate.py rule 10 refuses an explicit value faster than that, graded against
sum(unit_caps(opts)) - the roster sum, i.e. Controller.site_max_w - so a
second inverter moves the bound with no operator action.
VERIFIED BY BREAKING IT: restoring slew_w 1000 at max_w 5000 is refused, and the
refusal names the rail, the crossing time, the measurement and what to do.
Equality, one watt of slack, the live interim 400 and slew_w 0 at every rating
all still start.
GAIN IS THE CONSTANT THAT IS STILL WRONG, and it is NOT changed here. Over 51
export steps the over-absorption is FLAT in slew (958 W at 1000, 1081 W at 250)
and monotone in gain (987 W at 0.6, 876 at 0.3, 435 at 0.2): slew_w bounds the
OUTPUT, while the integrator moves gain*error per cycle and reaches a 5000 W
rail in under three ticks whatever the slew is. Two control-law constants moving
in one release on a running house makes the next measurement uninterpretable.
⚠️ N=2: the site rail becomes sum(max_w) ~ 9600 W (inverter B FROM DATASHEET AND
SERIAL, not measured, and sim/plantsim.py's INVERTER_B is A copied), and the
enforced ratio produces 1067 W there automatically. But a growing rail LOOSENS
this bound, and the >= 900 W symptom goes stale at N=2 the same way the constant
did - both stated in the record rather than left to be discovered.
Nothing reached the inverter. The live install still runs the interim slew_w 400
applied by hand on 2026-09-05, which rule 10 accepts unchanged.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BwRLw7eKYj2byVdwB6kbjU
adminandClaude Opus 5