Circuit Documentation

Summary of the Circuit

This circuit is designed to control a bulb and a DC motor using an Arduino UNO microcontroller and two 12V single-channel relays. The HC-05 Bluetooth module is included to provide wireless communication capabilities, potentially for remote control purposes. The Arduino UNO is programmed to interact with the relays, which in turn switch the high-power circuits for the bulb and the DC motor. The power for the circuit is provided by a DC power source and an AC wall plug point.

Component List

HC-05 Bluetooth Module

• Description: A Bluetooth module for wireless communication.
• Pins: Key, VCC, TXD, RXD, State, GND

12V Single Channel Relay (x2)

• Description: Electromechanical switches used to control high power devices.
• Pins: NC (Normally Closed), COM (Common), NO (Normally Open), IN (Input), GND, VCC

Arduino UNO

• Description: A microcontroller board based on the ATmega328P.
• Pins: UNUSED, IOREF, Reset, 3.3V, 5V, GND, Vin, A0-A5, SCL, SDA, AREF, D0-D13

Bulb

• Description: An electric light source.
• Pins: GND, power

DC Power Source

• Description: Provides the DC voltage required for the circuit.
• Pins: Ground, Positive

AC Wall Plug Point

• Description: Provides AC power from a wall outlet.
• Pins: E (Earth), N (Neutral), L (Live)

DC Motor

• Description: An electric motor powered by direct current.
• Pins: pin 1, pin 2

Wiring Details

HC-05 Bluetooth Module

• VCC connected to 5V power supply from Arduino UNO.
• TXD connected to D0 (RX) on Arduino UNO.
• RXD connected to D1 (TX) on Arduino UNO.
• GND connected to common ground.

12V Single Channel Relay (1st Instance)

• VCC connected to 5V power supply from Arduino UNO.
• GND connected to common ground.
• IN connected to D2 on Arduino UNO.
• COM connected to L from AC wall plug point.
• NO connected to power on the bulb.

12V Single Channel Relay (2nd Instance)

• VCC connected to 5V power supply from Arduino UNO.
• GND connected to common ground.
• IN connected to D3 on Arduino UNO.
• COM connected to Positive from DC Power Source.
• NO connected to pin 2 on the DC Motor.

Bulb

• GND connected to N from AC wall plug point.
• Power connected to NO on the 1st relay instance.

DC Motor

• Pin 1 connected to Ground from DC Power Source.
• Pin 2 connected to NO on the 2nd relay instance.

Arduino UNO

• 5V used to supply power to the Bluetooth module and both relays.
• GND used as common ground for the circuit.
• D0 (RX) connected to TXD on HC-05 Bluetooth Module.
• D1 (TX) connected to RXD on HC-05 Bluetooth Module.
• D2 connected to IN on the 1st relay instance.
• D3 connected to IN on the 2nd relay instance.

Documented Code

Arduino UNO Code (sketch.ino)

void setup() {
  // put your setup code here, to run once:

}

void loop() {
  // put your main code here, to run repeatedly:

}

Note: The provided code is a template and does not contain any functional code to control the relays or communicate with the HC-05 Bluetooth module. This will need to be implemented according to the specific requirements of the circuit's intended operation.