checks / unit (pull_request) Successful in 5m16s
`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