diff --git a/Functional-Description.md b/Functional-Description.md
index 34e06a0..2890481 100644
--- a/Functional-Description.md
+++ b/Functional-Description.md
@@ -170,25 +170,27 @@ Line-protocol payload for the `telemetry` bucket. Tags stay low-cardinality (sta
 The basin is modelled as a rectangular prism with constant cross-section. Everything derives from `volume = level × surfaceArea`.
 
 ```
-  GEOMETRY           ELEVATION             CONTROL (levelbased)
-
-  ═════════════   ◄─ heightBasin    ────   maxVol ≡ volume
-                      (freeboard)
-
-  ─ ─ ─ ─ ─ ─ ─   ◄─ heightOverflow ────   maxVolOverflow   ◄── overfill safety
-
-  ╌╌╌╌╌╌╌╌╌╌╌╌╌                      ────                   ◄── maxFlowLevel   (100% demand)
-                   LINEAR SCALING
-                   RANGE
-  ──●── INFLOW    ◄─ heightInlet    ────   minVolIn
-                                           
-  ╌╌╌╌╌╌╌╌╌╌╌╌╌                      ────                   ◄── startLevel     (0% demand)
-                   SEWAGE BUFFER
-  ┄┄┄┄┄┄┄┄┄┄┄┄┄                      ────                   ◄── stopLevel      (unconditional stop)
-                   DEAD ZONE                                     ↑ hysteresis band
-  ──●── OUTFLOW   ◄─ heightOutlet   ────   minVolOut         ◄── dry-run threshold
-                   DEAD VOLUME
-  ═════════════      0 (floor)
+                   ┌─────────────────┐  ◄─ heightBasin   (rim)
+                   │                 │
+                   │    freeboard    │
+                   ├─ ─ ─ ─ ─ ─ ─ ─ ─┤  ◄─ heightOverflow   ═══► overfill trip
+                   │≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈│                           (upstream stops)
+                   │≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈│
+                   ├╌ ╌ ╌ ╌ ╌ ╌ ╌ ╌ ╌┤  ◄─ maxFlowLevel     ═══► 100 % demand
+                   │≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈│                            ▲
+                   │≈≈≈≈≈ RUN ≈≈≈≈≈≈≈│                            │ ramp
+                   │≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈│                            │ linearly
+    INFLOW ═══════►╣≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈│  ◄─ heightInlet            │
+                   │≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈│                            │
+                   ├╌ ╌ ╌ ╌ ╌ ╌ ╌ ╌ ╌┤  ◄─ startLevel       ═══► 0 % demand
+                   │≈≈ DEAD ZONE ≈≈≈≈│                            ─── hysteresis
+                   │≈≈ (keep cmd) ≈≈≈│
+                   ├╌ ╌ ╌ ╌ ╌ ╌ ╌ ╌ ╌┤  ◄─ stopLevel        ═══► unconditional STOP
+                   │≈≈≈≈≈ BUFFER ≈≈≈≈│
+                   │≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈│
+    OUTFLOW ◄══════╣≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈≈│  ◄─ heightOutlet     ═══► dry-run trip
+                   │░░░ DEAD VOLUME ░│                           (downstream stops)
+                   └─────────────────┘  ◄─ 0 (floor)
 ```
 
 **Typical ordering** (bottom → top): `stopLevel < startLevel = minFlowLevel ≤ heightInlet < maxFlowLevel ≈ heightOverflow`.
@@ -241,23 +243,30 @@ flowPositions = { inflow: ['in', 'upstream'], outflow: ['out', 'downstream'] }
 ### `levelbased` mode — three zones
 
 ```
-                          demand
-                          ─────
-    maxFlowLevel   ──●─── 100 %  ─┐
-                     │             │  RUN
-                     │             │  (linear scaling)
-                     │             │
-    startLevel     ──●─── 0 %    ─┘
-                     │             ┐
-                     │             │  DEAD ZONE
-                     │             │  (hysteresis: keep last command)
-                     │             │
-    stopLevel      ──●─── stop   ─┘
-                     │             ┐
-                     │             │  STOP
-                     │             │  (unconditional MGC shutdown)
-                     │             │
-    floor          ──●             ┘
+     level
+       ▲
+       │
+       ┼── heightOverflow  ═══  overfill trip  ─►  upstream STOP
+       │
+       │                         ┐
+       │                         │  RUN
+       │                         │  linear 0 → 100 %
+       │                         │
+       ┼── maxFlowLevel    ═══   ┴  100 % demand
+       │
+       ┼── heightInlet     ───   inflow pipe
+       │
+       ┼── startLevel      ═══   0 % demand (ramp starts)
+       │                         ┐
+       │                         │  DEAD ZONE
+       │                         │  hysteresis — keep last cmd
+       │                         │
+       ┼── stopLevel       ═══   ┴  unconditional STOP
+       │
+       ┼── heightOutlet    ───   outflow pipe
+       │                   ═══   dry-run trip  ─►  downstream STOP
+       │
+       ┴── 0 (floor)
 ```
 
 - **STOP.** Below `stopLevel` every machine group receives `turnOffAllMachines()` and `percControl` is reset to `0`.