Circuit Documentation

Summary

The circuit in question is designed to interface an Arduino UNO microcontroller with an HC-05 Bluetooth module and control three 5V relay modules. The relays are used to switch various loads, including a 220V fan, a 220V red light, and a 120V outlet. The power for the circuit is provided by a 240V power source, which is also used to supply the high-voltage side of the relays for controlling the connected loads.

Component List

Arduino UNO

• Microcontroller board based on the ATmega328P
• It has 14 digital input/output pins, 6 analog inputs, a 16 MHz quartz crystal, a USB connection, a power jack, an ICSP header, and a reset button.

HC-05

• Bluetooth module for wireless communication
• It has 6 pins for enabling, power supply, ground, and serial communication.

1 Channel 5V Relay Module (x3)

• Electromechanical switch with an activation coil driven by 5V
• It has pins for power supply, ground, input signal, and switching contacts (normally open, common, and normally closed).

240V Power Source

• Provides the main power for the circuit and the loads controlled by the relays
• It has two pins for live and neutral wires.

Red Light 220VAC

• An indicator light that operates at 220V AC
• It has two pins for the AC connection.

120V Outlet

• A standard electrical outlet for 120V AC devices
• It has two pins for the AC neutral and hot connections.

220V Fan

• A fan that operates at 220V AC
• It has two pins for the AC live and neutral connections.

Wiring Details

Arduino UNO

• 5V pin is connected to the VCC of the HC-05 and the VCC+ of all relay modules.
• GND pin is connected to the GND of the HC-05 and the VCC- (GND) of all relay modules.
• D13 pin is connected to the IN pin of one relay module.
• D12 pin is connected to the IN pin of another relay module.
• D11 pin is connected to the IN pin of the third relay module.
• D1 pin (TX) is connected to the RXD pin of the HC-05.
• D0 pin (RX) is connected to the TXD pin of the HC-05.

HC-05

• VCC pin is connected to the 5V output from the Arduino UNO.
• GND pin is connected to the ground on the Arduino UNO.
• TXD pin is connected to the D0 (RX) on the Arduino UNO.
• RXD pin is connected to the D1 (TX) on the Arduino UNO.

1 Channel 5V Relay Module

• VCC+ pin is connected to the 5V output from the Arduino UNO.
• VCC- (GND) pin is connected to the ground on the Arduino UNO.
• IN pin is connected to a digital output (D13, D12, or D11) on the Arduino UNO.
• COM pin is connected to the live wire of the load it controls (fan, outlet, or light).
• N.C. pin is connected to the live wire from the 240V power source.

240V Power Source

• Live pin is connected to the N.C. pins of all relay modules.
• Neutral pin is connected to the neutral wire of the fan, outlet, and light.

Red Light 220VAC

• + pin is connected to the COM pin of one relay module.
• - pin is connected to the neutral wire from the 240V power source.

120V Outlet

• AC Hot pin is connected to the COM pin of one relay module.
• AC Neutral pin is connected to the neutral wire from the 240V power source.

220V Fan

• L pin is connected to the COM pin of one relay module.
• N pin is connected to the neutral wire from the 240V power source.

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:

}

The provided code is a template and does not contain any functional code for controlling the relays or interfacing with the HC-05 Bluetooth module. The user is expected to add the necessary code to initialize the serial communication with the HC-05 and to control the relay modules based on the commands received from the Bluetooth module.