Features: Hardware components: Arduino, relay module, jumper wires, and external power source Code: Arduino code for controlling the relay based on sensor input or a manual switch Applications: Home ...

Built your own arduino Relay Module for cheap using NPN transistor BC548 or darlington array ULN2003A - DIY-Arduino-Relay-Module/README.md at master · fikifir/DIY-Arduino-Relay-Module ...

The circuit diagram of contactless hand sanitiser dispensing system is shown in Fig. 2. It includes 12V power supply, Arduino Uno (Board1), ultrasoic sensor HC-SR04 (US1), 5V single-changeover relay ...

Resistance of relay coil is measured using a multimeter which turn out to be = 400 ohms. Vin pin of Arduino gives = 12v. So current need to turn on the relay = 12/400 Amps = 30 mA . If both relays are ...

Also, connect 12V power to all three relays, as shown in the circuit diagram. Upload Arduino source code (HomeAutomation.ino) to Arduino Uno. The source code can be downloaded by scanning the QR code ...

Arduino Nano; Sound sensor Module; 12V Relay Module; DC Pump; LEDs; Connecting wires; ... As shown in the above musical fountain circuit diagram, the sound sensor is powered with 3.3V supply of ...