SAFETY-73 review: a refusal needs 22 s of evidence, and the cut-out warning is for giving only

- REFUSED_SPAN_S: the 12 cycles of evidence must also span (SETTLE_CYCLES-1) *
  LOOP_TICK_S = 22 s. At a 1 s meter, lagged healthy readings refused both
  units 10-16 times an hour after load steps (site held 0 W). 2 s and slower
  ticks are unchanged.
- REFUSES_ABOVE_CUT_OUT only for a refusal to give power: a full battery that
  stops taking charge is always above its cut-out level.
- test_delivery: its wedged fixture (0.2 s cycles) no longer reaches a refusal;
  the release/1.0 checks are restored and a span check added.
- test_refusal_units: lagged-reading and full-battery plants, two new checks,
  U14/U15 in the mutation table. Stale "> 500 W" wording fixed. DOCS/DECISIONS.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

goodwe_controller/DECISIONS/SAFETY-73-refusal-per-inverter.md

@@ -26,14 +26,15 @@ standing import, new -16 W. Both cut out: old keeps asking two empty batteries
 
 1. **A refusing unit is closed in that direction** by its own P_SAFETY unit
    claim, source `refused`. It engages when the unit gives under
-   `REFUSED_BELOW_W` (100 W) for `SETTLE_CYCLES` (12) cycles in one direction
-   while asked more than `PROBE_W` (200 W), or when its stale-reading gate
+   `REFUSED_BELOW_W` (100 W) for `SETTLE_CYCLES` (12) cycles, spanning at least
+   `REFUSED_SPAN_S` (22 s), in one direction while asked more than `PROBE_W`
+   (200 W), or when its stale-reading gate
    trips on a held reading under 100 W. The allocator then hands its share to
    the others within their own limits (owner decision 1). It is a hard unit
    limit that always intersects, so OPT-11's P_MODE layer fits inside it.
 2. **It binds every strategy's ask on that unit** (decision 2): peak guard,
    arbitrage and maintenance are placed around it like the loop.
-3. **A refusal above the configured cut-out** logs INFO plus one WARNING ending
+3. **A refusal to give power above the configured cut-out** logs INFO plus one WARNING ending
    in `REFUSES_ABOVE_CUT_OUT` (decision 3). SAFETY-42/43 no longer report such a
    unit: its share is 0 W, and `account()` treats it as parked.
 4. **All units refusing the same way** pass that sign to `compute()`, so the
@@ -79,6 +80,20 @@ SAFETY-73 method made to raise.
   target: worst grid +0 W with the reseed. Phase A measured -1059 W without the
   reseed and the site hold.
 
+## Review changes
+
+- **The evidence must span 22 s, not only 12 cycles.** At a 1 s meter the 12
+  cycles were 11 s, shorter than a healthy reading's lag (dead time plus a
+  10-17 s publish). The reviewer's harness (real `Controller`, both units with
+  6 s dead time and a 13-17 s publish, load steps 300/3000 W every 2 min) then
+  refused both healthy units 10-16 times an hour, and each time the site held
+  0 W: +50-85 Wh import an hour and a +4.6 kW grid peak against +3.7 kW without
+  the refusal. At a 2 s tick there were none. `REFUSED_SPAN_S` is
+  `(SETTLE_CYCLES - 1) * LOOP_TICK_S`, so 2 s and slower ticks are unchanged.
+- **The cut-out WARNING is for a refusal to give power only.** A full battery
+  that stops taking charge is always above its cut-out level, and the WARNING
+  told the installer to check a setting that has nothing to do with it.
+
 ## Not covered
 
 - A unit that gives a steady part of its ask (100 W or more) is a limit, as at

goodwe_controller/DOCS.md

@@ -551,15 +551,15 @@ needs, so a test never trips it. A battery that gives some power, even 100 W,
 is not refusing and keeps its request.
 
 **With two or more inverters** the same rule works per inverter. An inverter
-whose battery gives less than 100 W for 12 cycles while asked for more than
-200 W is asked 0 W, and the other inverters take over its share, each up to
+whose battery gives less than 100 W for 12 cycles, and at least 22 s, while
+asked for more than 200 W is asked 0 W, and the other inverters take over its share, each up to
 its own limits. The status page names it: *inverter-a: the battery refuses to
 give power, the others take over*. It is tested at 200 W every 15 minutes, one
 inverter at a time, and only while the site asks at least 200 W that way.
-It still accepts charge, and a minute of charging ends the refusal. When every
+It still accepts charge, and 12 cycles of charging end the refusal. When every
 inverter refuses the same way, the whole site asks 0 W as with one inverter.
-If the battery refuses while its level reads above its “Battery cut-out level”,
-the log adds one warning ending in `REFUSES_ABOVE_CUT_OUT`: check that setting.
+If the battery refuses to give power while its level reads above its “Battery
+cut-out level”, the log adds one warning ending in `REFUSES_ABOVE_CUT_OUT`: check that setting.
 A battery that refuses is not reported as *not delivering*.
 
 *For installers:* SAFETY-52 and SAFETY-73. The event log reads

goodwe_controller/app/inverter.py

@@ -319,12 +319,14 @@ class Inverter:
 
         # SAFETY-73. The direction this unit's battery refuses (+1 give, -1
         # take, 0 none), when that refusal or its last probe started, the
-        # current probe's start, and the cycles of evidence so far. Memory
-        # only, like SAFETY-52's: stop and start end it. Used at N>1 only.
+        # current probe's start, and the cycles of evidence so far and when
+        # they began. Memory only, like SAFETY-52's: stop and start end it.
+        # Used at N>1 only.
         self.refused = 0
         self.refused_at = None
         self.probe_from = None
         self.ref_count = 0
+        self.ref_since = None
         self.ref_sign = 0
 
     # -- store ---------------------------------------------------------------

goodwe_controller/app/main.py

@@ -236,6 +236,15 @@ def pack_energy_of(inv):
                                 inv.capacity_kwh, inv.max_w)
 
 
+# SAFETY-73 review: the evidence must also span this long, not only
+# SETTLE_CYCLES cycles. SETTLE_CYCLES was derived at the 2 s meter tick (22 s
+# from its first to its twelfth cycle). A 1 s meter makes 12 cycles only 11 s,
+# shorter than a healthy battery reading's lag (BATT_OBLIGED_S, 17 s, plus the
+# plant's dead time), and both inverters of a site were then refused after
+# ordinary load steps. At 2 s and slower this changes nothing.
+REFUSED_SPAN_S = (_ctl.SETTLE_CYCLES - 1) * _ctl.LOOP_TICK_S
+
+
 def _refused_interval(sign: int) -> tuple:
     """SAFETY-73: the (lo, hi) a refusing unit may be asked: 0 W that way."""
     return (-math.inf, 0.0) if sign > 0 else (0.0, math.inf)
@@ -1171,7 +1180,9 @@ class Controller:
         _LOG.info("%s: the battery refuses power, so it is asked 0 W and the "
                   "other inverters take over: BATTERY_REFUSES.", inv.name)
         _LOG.debug("Evidence for %s: BATTERY_REFUSES: %s.", inv.name, evidence)
-        if (inv.soc is not None and inv.bms_soc_floor is not None
+        # Only a refusal to GIVE: a full battery that stops taking charge is
+        # above its cut-out level by definition and says nothing about it.
+        if (sign > 0 and inv.soc is not None and inv.bms_soc_floor is not None
                 and float(inv.soc) > float(inv.bms_soc_floor)):
             # Owner decision 3: a refusal above the configured cut-out level
             # may mean that level is set wrong. One line, no safety stop.
@@ -1243,12 +1254,15 @@ class Controller:
             # (a flapping load) reads ~0 through the plant's own lag, and that
             # is a battery following, not refusing (TEST-19 flapping family).
             if abs(standing) > _ctl.PROBE_W and abs(b) < _ctl.REFUSED_BELOW_W:
-                inv.ref_count = (min(inv.ref_count + 1, _ctl.SETTLE_CYCLES)
-                                 if sign == inv.ref_sign else 1)
+                if sign != inv.ref_sign or not inv.ref_count:
+                    inv.ref_count, inv.ref_since = 0, self._now_mono
+                inv.ref_count = min(inv.ref_count + 1, _ctl.SETTLE_CYCLES)
             else:
                 inv.ref_count = 0
             inv.ref_sign = sign
-            if inv.ref_count >= _ctl.SETTLE_CYCLES:
+            if inv.ref_count >= _ctl.SETTLE_CYCLES and (
+                    inv.ref_since is None or self._now_mono is None
+                    or self._now_mono - inv.ref_since >= REFUSED_SPAN_S):
                 self._unit_refusal_start(
                     inv, sign,
                     f"asked {standing:+.0f} W, the battery gave {b:+.0f} W "

goodwe_controller/test_delivery.py

@@ -592,21 +592,16 @@ check("...and the SHARES now differ, which is OPT-09 and not a weakening of the
       "cards meet here from opposite sides: OPT-09 stops the ASK, this file "
       "grades the ALARM, and neither can do the other's half",
       _pw != _pf
-      and _sf[-1]["shares"][1] == 0.0
-      and max(r["shares"][1] for r in _sw) == 2000.0)
-# SAFETY-73. A unit that gives < 100 W for 12 cycles while asked > 500 W is a
-# battery that refuses (owner, 2026-09-27): it is closed, its share moves, and
-# SAFETY-42 is left with units that deliver something but not enough. This
-# fixture compresses `delivery_hold_s` to 1 s at 0.2 s cycles, so the report
-# still comes first here. On a site 185 s against 60 s puts the refusal first.
-_ref_at = next((i for i, r in enumerate(_sw) if r["shares"][1] == 0.0), None)
-check("SAFETY-73: the wedged arm's B, giving 0 W against 2000 W, is refused "
-      "after 12 cycles of that evidence and asked 0 W from then, the report "
-      "having come first only because this fixture's hold is 1 s",
-      _ref_at is not None and _ref_at >= control.SETTLE_CYCLES
-      and all(r["shares"][1] > 0 for r in _sw[:_ref_at])
-      and all(r["shares"][1] == 0.0 for r in _sw[_ref_at:])
-      and _cw.inverters[1].refused == 1)
+      and _sf[-1]["shares"][1] == 0.0 and _sw[-1]["shares"][1] == 2000.0)
+# SAFETY-73. A unit that gives < 100 W while asked > 200 W is refused after
+# SETTLE_CYCLES cycles that also span REFUSED_SPAN_S (22 s). This fixture's 14
+# cycles are 0.2 s apart, so the wedged B meets the count and not the span, and
+# SAFETY-42's report stands alone here. test_refusal_units.py grades the
+# refusal. On a site the 185 s hold puts the refusal first.
+check("SAFETY-73: the wedged arm's B is not refused in this fixture: 12 cycles "
+      "of evidence in under 3 s are not the 22 s a refusal needs",
+      _cw.inverters[1].refused == 0
+      and _cw.inverters[1].ref_count >= control.SETTLE_CYCLES)
 check("...and the state of charge is still what tells them apart",
       [r["soc"] for r in _sw] != [r["soc"] for r in _sf])
 print(f"       both arms, last cycle: grid {_sw[-1]['grid']:.0f} W, shares "
@@ -654,10 +649,10 @@ check("...and `account()` STILL turns this pack away if the ask does arrive - "
       account(live=True, parked=False, soc=_cold_b.soc,
               bms_floor=_cold_b.bms_soc_floor) is not None)
 check("...and the WEDGED arm's B differs from it in exactly that one place - "
-      "which is why it was asked for its share until the refusal, and named",
+      "which is why it is still asked for its share, and still named",
       account(live=True, parked=False, soc=_cw.inverters[1].soc,
               bms_floor=_cw.inverters[1].bms_soc_floor) is None
-      and _sw[0]["shares"][1] > 0 and _sw[-1]["named"] == ("inverter-b",))
+      and float(_cw.inverters[1].standing_w()) > 0)
 
 # ⚠️ WHICH FLOOR, AND THIS IS A WIRING CHECK THAT THE PURE ONES ABOVE CANNOT
 # MAKE. `peakguard.pack_floor_pct()` conjoins a pack's own cut-out with the
@@ -930,13 +925,9 @@ check("...and EVERY WATT IS THE SAME. Grid, site target, both shares and both "
       "reported or not - which is what 'it does not act' means, stated as a "
       "measurement instead of as an intention",
       _power_domain(_sw) == _power_domain(_sn))
-_trip_at = next((i for i, r in enumerate(_sw) if r["named"]), None)
-check("...the wedged unit is still commanded its share after the trip, not "
-      "parked by this guard: this is NOT SAFETY-02's remedy. What later takes "
-      "the share is SAFETY-73's refusal, which runs the same in the arm where "
-      "this guard never trips (the line above)",
-      _trip_at is not None and _ref_at is not None and _trip_at < _ref_at
-      and all(r["shares"][1] > 0 for r in _sw[_trip_at:_ref_at]))
+check("...the wedged unit is still being commanded its share after the trip, "
+      "not parked: this is NOT SAFETY-02's remedy and must not become it",
+      abs(float(_cw.inverters[1].target)) > 0)
 check("...and nothing named `delivery` reaches the arbiter - the resolution's "
       "own sentence is unchanged by the trip",
       "deliver" not in _cw.reason.lower() and _cw.reason == _cn.reason)

goodwe_controller/test_refusal_units.py

@@ -1,7 +1,7 @@
 """Runnable check for SAFETY-73.  `python3 test_refusal_units.py`
 
 SAFETY-52 per inverter. With two or more inverters, a battery that refuses
-(gives < 100 W for 12 cycles while asked > 500 W, or trips the stale-reading
+(gives < 100 W for 12 cycles and 22 s while asked > 200 W, or trips the stale-reading
 gate on a ~0 W reading) is closed in that direction by its own P_SAFETY limit,
 so the allocator hands its share to the others. It is probed at 200 W every
 15 minutes, one inverter at a time. When every inverter refuses the same way
@@ -33,6 +33,8 @@ over this file / test_delivery / test_refusal. Every one is red here:
   U11  main.py: the above-cut-out WARNING condition inverted        1/0/0
   U12  main.py: SAFETY-42's account no longer sees a small ask      1/0/0
   U13  main.py: a unit engages above `saturation_w`, not PROBE_W    1/0/0
+  U14  main.py: the evidence need not span REFUSED_SPAN_S (review)  1/0/0
+  U15  main.py: the WARNING also for a refusal to take (review)     1/0/0
 
 On 652097a itself this file stops at the first sample (`Inverter` has no
 `refused`); its OLD arms reproduce that tree's N>1 behaviour instead, and
@@ -61,6 +63,7 @@ def check(name, cond):
 
 TICK = 5.0
 CUT_W = -4.0
+FULL_W = 40.0
 H = 3600.0
 BASE = datetime(2026, 9, 6, 19, 30, tzinfo=timezone.utc)
 UNITS = ("a", "b")
@@ -89,23 +92,39 @@ class _Pub:
 
 
 class _Hass:
-    """A house, one meter, and two batteries that follow unless cut out."""
+    """A house, one meter, and two batteries that follow unless cut out.
 
-    def __init__(self, load, cut, soc, jitter):
+    `lag` (review): (dead s, publish s). Each battery reading then shows the
+    power of `dead` s before its last publish; the power itself and the meter
+    follow at once. `full[u](t)`: that battery takes at most FULL_W of charge.
+    """
+
+    def __init__(self, load, cut, soc, jitter, lag=None, full=None):
         self.load, self.cut, self.soc, self.jitter = load, cut, soc, jitter
+        self.lag, self.full = lag, full or {}
         self.cmd = {u: 0.0 for u in UNITS}
+        self.hist = {u: [(-1e18, 0.0)] for u in UNITS}
         self.t = 0.0
 
-    def batt(self, u):
-        c = self.cmd[u]
-        if self.cut[u](self.t) and c >= CUT_W:
+    def power(self, u, t=None):
+        t = self.t if t is None else t
+        c = next((v for tt, v in reversed(self.hist[u]) if tt <= t), 0.0)
+        if self.cut[u](t) and c >= CUT_W:
             if self.jitter:
-                return CUT_W + ((int(self.t / TICK) % 3) - 1) * 3.0
+                return CUT_W + ((int(t / TICK) % 3) - 1) * 3.0
             return CUT_W
+        if u in self.full and self.full[u](t) and c < -FULL_W:
+            return -FULL_W
         return float(round(c))
 
+    def batt(self, u):
+        if self.lag is None:
+            return self.power(u)
+        dead, pub = self.lag
+        return self.power(u, (self.t // pub) * pub - dead)
+
     def grid(self):
-        return self.load(self.t) - sum(self.batt(u) for u in UNITS)
+        return self.load(self.t) - sum(self.power(u) for u in UNITS)
 
     async def limits(self, e):
         return (-2000.0, 2000.0, 1.0)
@@ -126,6 +145,7 @@ class _Hass:
 
     async def set_number(self, e, v):
         self.cmd[e[-1]] = float(v)
+        self.hist[e[-1]].append((self.t, float(v)))
         return True
 
 
@@ -136,10 +156,12 @@ def _off(c):
 
 
 def run(load, cut, dur, *, soc=None, jitter=False, old=False, events=None,
-        extra=None):
+        extra=None, tick=None, lag=None, full=None):
     """Real cycles every TICK of simulated time. Rows are dicts per cycle."""
     async def go():
-        hass = _Hass(load, cut, soc or {"a": 50.0, "b": 50.0}, jitter)
+        hass = _Hass(load, cut, soc or {"a": 50.0, "b": 50.0}, jitter, lag,
+                     full)
+        dt = tick or TICK
         inv = [{"name": f"inverter-{u}", "setpoint_entity": f"number.sp_{u}",
                 "soc_entity": f"sensor.soc_{u}",
                 "batt_entity": f"sensor.batt_{u}",
@@ -187,7 +209,7 @@ def run(load, cut, dur, *, soc=None, jitter=False, old=False, events=None,
                     ra=c.inverters[0].refused, rb=c.inverters[1].refused,
                     da=c.inverters[0].delivery_wd.tripped,
                     db=c.inverters[1].delivery_wd.tripped))
-                t += TICK
+                t += dt
         finally:
             m.datetime = real_dt
         return rows, trips, c
@@ -448,6 +470,41 @@ check("shadow mode: no inverter is refused and both stay at 0 W",
       c.inverters[0].refused == 0 and c.inverters[1].refused == 0
       and all(r["a"] == 0.0 and r["b"] == 0.0 for r in rows))
 
+# Review. A 1 s meter makes 12 cycles 11 s, shorter than a healthy battery
+# reading's lag (6 s dead time plus a 13 s publish). Ordinary load steps then
+# refused both inverters and dropped the site to 0 W (16 times an hour). The
+# evidence must also span REFUSED_SPAN_S.
+_steps = (lambda t: 300.0 if int(t // 120) % 2 == 0 else 3000.0)
+rows, _, c = run(_steps, {"a": never, "b": never}, H, tick=1.0,
+                 lag=(6.0, 13.0))
+check("a 1 s meter and slow battery readings: load steps for an hour refuse "
+      "neither healthy inverter",
+      not any(r["ra"] or r["rb"] for r in rows))
+rows, _, c = run(lambda t: 3000.0, {"a": cut_at(120), "b": never}, 600,
+                 tick=1.0, lag=(6.0, 13.0))
+_eng = next((r["t"] for r in rows if r["ra"]), None)
+check("...and the same slow readings still refuse a battery that is cut "
+      "out, after the span and well inside the 185 s report",
+      _eng is not None and 120 + m.REFUSED_SPAN_S <= _eng < 185
+      and not any(r["da"] for r in rows))
+
+# Review. A full battery that stops taking charge is refused (charge), and
+# it is always above its cut-out level: that says nothing about the setting,
+# so it gets the INFO line and no REFUSES_ABOVE_CUT_OUT warning.
+_g2 = _Grab()
+_lg.setLevel(logging.INFO)
+_lg.addHandler(_g2)
+rows, _, c = run(lambda t: -3000.0, {"a": never, "b": never}, 600,
+                 soc={"a": 99.0, "b": 60.0}, full={"a": lambda t: t >= 120})
+_lg.removeHandler(_g2)
+_lg.setLevel(_lv)
+check("a full battery that stops taking charge is refused that way only, "
+      "with the INFO line and no warning about its cut-out level",
+      c.inverters[0].refused == -1
+      and any(lv == logging.INFO and "BATTERY_REFUSES" in x
+              for lv, x in _g2.lines)
+      and not any("REFUSES_ABOVE_CUT_OUT" in x for _lv2, x in _g2.lines))
+
 # ==============================================================================
 print("6. one inverter is untouched")
 # ==============================================================================