The four diagrams that explain the Wattplot controller: the system block, the power flow, the state machine, and the assembly sequence. All rendered as scalable SVG so they stay sharp at any size and stay editable as code.
Every component, every signal. ESP32-S3 in the center; power from the top, motor + solenoid to the sides, sensors at the bottom, WiFi to the upper-right. Lines are color-coded: power, signal (analog/digital), control.
Volts and amps from panel to load. The 5 V rail feeds the MCU and the H-bridge nFAULT inputs. The 3.3 V rail powers the ESP32-S3. The 12 V battery rail feeds both H-bridges. Battery voltage is divided to ~1.09 V and read on GPIO7 to track state of charge.
The controller has four states. Normal runs the PI loop. Monitoring waits 15 min to see if the wind passes. Folding drives to 0° until current-spike indicates endstop. Locked holds for 30 min before re-checking. Boot defaults to Folding (safe).
Six-step build. Total: 3–4 hours, ~$193 in parts. The bed and panel are separate sub-assemblies; join them at step 5. Do all electrical work in step 6 with the battery DISCONNECTED and the panel covered with an opaque tarp.
Wattplot