From a600b59809a70ce03160acb4fcb33fc07b45ce61 Mon Sep 17 00:00:00 2001
From: Codex Agent <codex@example.com>
Date: Fri, 28 Nov 2025 20:56:34 +0100
Subject: [PATCH] Show filtered power on trends and ease DNB SCRAM threshold

---
 src/reactor_sim/dashboard.py | 8 +++++---
 src/reactor_sim/reactor.py   | 4 +++-
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/reactor_sim/dashboard.py b/src/reactor_sim/dashboard.py
index ab34c36..d8f6f63 100644
--- a/src/reactor_sim/dashboard.py
+++ b/src/reactor_sim/dashboard.py
@@ -433,7 +433,7 @@ class ReactorDashboard:
             left_win,
             left_y,
             "Trends",
-            self._trend_lines(),
+            self._trend_lines(state),
         )
         left_y = self._draw_section(left_win, left_y, "Key Poisons / Emitters", self._poison_lines(state))
         left_y = self._draw_section(
@@ -820,9 +820,9 @@ class ReactorDashboard:
     def _update_trends(self, state: PlantState) -> None:
         self._trend_history.append((state.time_elapsed, state.core.fuel_temperature, state.core.power_output_mw))
 
-    def _trend_lines(self) -> list[tuple[str, str]]:
+    def _trend_lines(self, state: PlantState) -> list[tuple[str, str]]:
         if len(self._trend_history) < 2:
-            return [("Fuel Temp Δ", "n/a"), ("Core Power Δ", "n/a")]
+            return [("Fuel Temp Δ", "n/a"), ("Core Power Δ", "n/a"), ("P(meas)", "n/a")]
         start_t, start_temp, start_power = self._trend_history[0]
         end_t, end_temp, end_power = self._trend_history[-1]
         duration = max(1.0, end_t - start_t)
@@ -830,9 +830,11 @@ class ReactorDashboard:
         power_delta = end_power - start_power
         temp_rate = temp_delta / duration
         power_rate = power_delta / duration
+        measured = getattr(self.reactor.control, "_filtered_power_mw", 0.0) if hasattr(self.reactor, "control") else 0.0
         return [
             ("Fuel Temp Δ", f"{end_temp:7.1f} K (Δ{temp_delta:+6.1f} / {duration:4.0f}s, {temp_rate:+5.2f}/s)"),
             ("Core Power Δ", f"{end_power:7.1f} MW (Δ{power_delta:+6.1f} / {duration:4.0f}s, {power_rate:+5.2f}/s)"),
+            ("P(meas)", f"{measured:7.1f} MW" if measured > 0 else "n/a"),
         ]
 
     def _draw_health_bars(self, win: "curses._CursesWindow", start_y: int) -> int:
diff --git a/src/reactor_sim/reactor.py b/src/reactor_sim/reactor.py
index fcaf12b..ab73f94 100644
--- a/src/reactor_sim/reactor.py
+++ b/src/reactor_sim/reactor.py
@@ -446,10 +446,12 @@ class Reactor:
         if (not self.secondary_pump_active or state.secondary_loop.mass_flow_rate <= 1.0) and total_power > 50.0:
             self._handle_heat_sink_loss(state)
         # SCRAM matrix: DNB, subcooling, steam generator level/pressure
-        if state.core.dnb_margin is not None and state.core.dnb_margin < 0.5:
+        if state.core.dnb_margin is not None and state.core.dnb_margin < 0.45:
             LOGGER.critical("DNB margin low: %.2f, initiating SCRAM", state.core.dnb_margin)
             self.shutdown = True
             self.control.scram()
+        elif state.core.dnb_margin is not None and state.core.dnb_margin < 0.6:
+            LOGGER.warning("DNB margin low: %.2f", state.core.dnb_margin)
         if state.core.subcooling_margin is not None and state.core.subcooling_margin < 2.0:
             LOGGER.critical("Subcooling margin lost: %.1fK, initiating SCRAM", state.core.subcooling_margin)
             self.shutdown = True