glenn schrooyenandClaude Opus 5.5
7c4c8f5c66
New option peak_margin_w (default 50 W, 0-500 W). The peak guard, the
forecast checks and the maintenance charge sizing aim at
peak_cap_w - peak_margin_w; the month peak, the bill, headroom, warnings
and every notice keep the real cap. Owner decision 2026-09-28.
peak_margin_w 0 is byte-identical to ed739d4 (tools/safety79_identity.py,
test_peak_margin.py part 1). validate.py rule 12 refuses a value outside
0-500, not whole, or not below the peak limit.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UBtqPrG1mDLXzTEBnhEkkV
1.6 KiB
SAFETY-79 — the peak guard keeps a margin below the peak limit
Status: DECIDED 2026-09-28 (owner decision).
Decision
The peak guard aims at peak_cap_w - peak_margin_w, not at peak_cap_w.
peak_margin_w is a setting: default 50 W, range 0-500 W, whole watts. An
install without the key gets 50.
Why (owner): the guard aimed exactly at the cap, and in the OPT-11 P1 test a quarter banked 3501.9 W against a 3500 W limit (OPT-11-P1-test-report.md, check 4). A peak even 1 W over still sets the billed peak. It is a setting and not a constant because the add-on is sold to several sites.
What uses which number
- cap - margin (the aim):
peakguard.decide()(the claim's floor, and so arbitrage'scharge_headroom_w()and OPT-11's give-way, which read it),shaping_suspended()andmaintenance_charge_floor()(the forecast checks, viaController.peak_aim_w()). - the real cap (reporting and billing):
PeakTracker(month peak, headroom, 80 % warning), the decision'sceiling_wand every notice and status row built from it, Home's limit, andvalidate.config_notes().
A month peak already banked above cap - margin is aimed at as it stands
(quarter_target_w() is quarter_ceiling_w() on the lowered cap), so the
margin never holds a quarter below a peak that is already paid for.
Checks
peak_margin_w: 0 is byte-identical to ed739d4 (test_peak_margin.py part 1,
digests from tools/safety79_identity.py). validate.py rule 12 refuses a value
outside 0-500, not whole, or not below peak_cap_w.
Open
Whether the margin should also apply below a banked month peak above the cap is not decided here; today it does not.