Circuit Documentation

Summary

This circuit is designed to interface various sensors, actuators, and control elements with an Arduino UNO microcontroller. The circuit includes gas and flame sensors for environmental monitoring, a piezo buzzer for audible alerts, a water pump for fluid control, a MOSFET and an NPN transistor for switching, resistors for current limiting and voltage division, a 5V relay for controlling higher power loads, and a 12V battery for power supply.

Component List

Sensors

• MQ-2 Gas Sensor: Detects various gases such as LPG, i-butane, methane, alcohol, Hydrogen, smoke.
• Sensor SHT113 Flame: Detects the presence of a flame or fire.

Actuators

• Piezo Buzzer: Emits an audible alert or tone.
• Water Pump: Pumps water when activated.

Control Elements

• Arduino UNO: A microcontroller board based on the ATmega328P, used for controlling the logic of the circuit.
• NPN-Transistor: A bipolar junction transistor used for switching or amplification.
• Mosfet: A type of field-effect transistor used for switching electronic signals.
• 5v Relay: An electromechanical switch used for turning on/off a circuit with a separate low-power signal.

Power Supply

• 12V Battery: Provides the power required for the circuit.

Passive Components

• Resistor (1k Ohm): Limits current or divides voltage in the circuit.
• Resistor (10k Ohm): Provides a pull-up or pull-down resistance or limits current.

Wiring Details

MQ-2 Gas Sensor

• VCC: Connected to the 5V supply from the Arduino UNO.
• GND: Connected to the ground net, shared with other components.
• A0: Not connected in this circuit.
• D0: Connected to the A4 pin on the Arduino UNO.

Sensor SHT113 Flame

• VCC: Connected to the 5V supply from the Arduino UNO.
• GND: Connected to the ground net, shared with other components.
• A0: Connected to the A3 pin on the Arduino UNO.
• D0: Not connected in this circuit.

Piezo Buzzer

• Pin 1: Connected to the 5V supply from the Arduino UNO.
• Pin 2: Connected to the emitter (E) of the NPN-Transistor.

Water Pump

• VCC: Connected to the Vin pin on the Arduino UNO and the VCC of the 12V Battery.
• GND: Connected to the drain (Drain) of the Mosfet.

NPN-Transistor

• E (Emitter): Connected to pin 2 of the Piezo Buzzer.
• C (Collector): Connected to pin 1 of a 1k Ohm Resistor.
• B (Base): Connected to pin 2 of a 10k Ohm Resistor and the ground net.

Mosfet

• Gate: Connected to pin D5 on the Arduino UNO and pin 2 of a 10k Ohm Resistor.
• Drain: Connected to the GND of the Water Pump.
• Source: Connected to the ground net.

Resistor (1k Ohm)

• Pin 1: Connected to the collector (C) of the NPN-Transistor.
• Pin 2: Not connected in this circuit.

Resistor (10k Ohm)

• Pin 1: Connected to the base (B) of the NPN-Transistor.
• Pin 2: Connected to the gate (Gate) of the Mosfet and pin D5 on the Arduino UNO.

5v Relay

• Normally Open (NO): Not connected in this circuit.
• Common Terminal (COM): Connected to the 5V supply from the Arduino UNO.
• Normally Closed (NC): Connected to the ground net.
• In: Not connected in this circuit.
• GND: Connected to the ground net.
• VCC: Connected to the 5V supply from the Arduino UNO.

12V Battery

• VCC: Connected to the Vin pin on the Arduino UNO and the VCC of the Water Pump.
• GND: Connected to the ground net.

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 logic. It needs to be populated with the specific instructions to control the circuit based on the desired application.