Overview
Traditional Reverse Osmosis (RO) water purification units operate blind: users have no visibility into membrane fouling, filter cartridge lifespan, inlet water pressure, or actual pure water production rate until water quality degrades noticeably.
The Smart RO System is an IoT retrofit module that bridges high-voltage/24V industrial RO pump and solenoid hardware with modern embedded wireless monitoring and control.
Power & Hardware Isolation Architecture
RO systems operate high-pressure booster pumps and solenoid valves at 24V DC, which generates significant inductive switching transients:
- Galvanic Isolation: PC817 optocouplers and flyback Schottky diodes isolate the 3.3V ESP8266 logic from 24V solenoid spikes.
- Sensor Suite:
- Dual in-line TDS probes: Measuring raw inlet water versus permeate output to compute instantaneous membrane rejection rate ($R%$).
- High/Low Pressure Switches: Monitoring feed pressure failure and tank full shutoff states.
- Flow Rate Turbine Sensor: Tracking cumulative liters filtered to predict cartridge replacement schedules.
- Fail-Safe Relay Cutoff: Automatic emergency motor cutoff if leakage sensors detect water accumulation in the bottom tray.
Cyberpunk Web Interface & Firmware
- Embedded Web Server on LittleFS: High-contrast, neon-accented cyberpunk UI served directly from ESP8266 flash.
- Real-Time Control & Telemetry:
- Digital manual override: Remote flush solenoid trigger and booster pump toggle.
- Visual gauge indicators: Water purity efficiency, TDS reduction percentage, and cartridge life remaining.
- WiFi Captive Portal: Seamless initial configuration for home/industrial WiFi credentials.
Repository & Schematics
Full electrical schematics, PCB layout, and LittleFS web assets are published on GitHub - Smart-RO-System.