The clamp was never the missing half. specs.md 10.3 records an unclamped
integrator climbing ~130 W per 4 s past 10 kW and reporting 14 768 W pinned at
the 5 kW rail; clipped silently that is a flat, legal-looking 5000 W hold and
nothing says the loop asked for three times it.
write_setpoint() - the one path every write takes - now clamps to the VALIDATED
max_w and reports whether the raw value differed; check_output_clamp() raises
OUTPUT_CLAMP as a notification, an ERROR, an event row and a red status banner.
Not a trip: the clamped value is written and the loop keeps running.
The rating is max_w and nothing is min()ed at runtime - CFG-01 already refuses a
max_w outside the device range at startup. The device range is applied second as
defence in depth; it cannot bite after a successful validation, so if it ever
does it alarms too and names the bound. No new config key.
Decision grew i_clamped / clamped booleans, and that is the load-bearing part:
`reason` is one string that slew-limiting and the saturation freeze overwrite,
so an alarm keyed on it is silent on exactly the cycles a winding loop produces.
Mutating main.py back onto the string drops the 10.3 replay from 2 engagements
to 0.
Distinct from saturation by construction - no shared reason code, notification
id, status row or counter - and checked in the negative, after first asserting
the saturation freeze really did engage.
Two things found by running it rather than by reading it: a row per engagement
flushed the 40-row event log and evicted SAFETY-18's own METER FROZEN? row (now
coalesced per episode with an exact count), and a naive clamp turns a nan into a
command at the full rating because every comparison against nan is False.
test_clamp.py is new: assert-based, no framework. Six author mutations
reproduced red, including "clamp kept, alarm deleted". Two of the check's own
hypotheses about the freeze/clamp interaction were refused by its sweep and
rewritten to what it measured.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015VXjA3LWccN1rJsk3okyPC
