Introduction of wireless gas leakage detector alarm

The project that i being doing for my final year project is wireless gas leakage detector alarm. Wireless gas leakage alarm is a alarm that being used to detect gas leakage in industry,house or office.For my project the specified gas can be detected is LPG gas which is liquefied petroleum gas.This is because the sensor that being used for this project is MQ-4.This project is used to detect a gas leak and interface with a control system so a process can be automatically shut down. For this project i'm using alarm to be the output for the project,this is to give a warning for the employees or public people to alert to the leak of gas and giving them the opportunity to leave the area. This type of device is important because the gas can that can be harmful to organic life, such as humans or animals.

   

          This project is using direct supply for both Tx and Rx.  When dangerous levels of gas vapors are detected. As detectors measure a gas concentration, the sensor responds to a calibration gas, which serves as the reference point or scale. As a sensor’s detection exceeds a preset alarm level, the alarm or signal will be activated. As units, gas detectors are produced as portable or stationary devices. Originally, detectors were produced to detect a single gas, but modern units may detect several toxic or combustible gases, or even a combination of both types.

          

Types

There are several types of the gas leakage detector as shown below:

1.)Electrochemical Detectors

Electrochemical gas detectors work by allowing gases to diffuse through a porous membrane to an electrode where it is either oxidized or reduced. 

2.)Infrared Point Detectors

Infrared (IR) point sensors use radiation passing through a volume of gas to detect leaks. Energy from the radiation is absorbed as it passes through the gas at certain wavelengths. 

3.)Infrared Imaging Detectors

Infrared point sensors are active measurement systems, in that they typically measure the absorption of a gas by passing it through a laser-illuminated chamber and measuring the change in transmitted signal. 

4.)Semiconductor Detectors

Semiconductor sensors detect gases by a chemical reaction that takes place when the gas comes in contact with the sensor. 

5.)Ultrasonic Detectors

Ultrasonic gas detectors use acoustic sensors to detect changes in the background noise of its environment. Since most gas leaks occur in the ultrasonic range of 25 kHz to 10 MHz, the sensors are able to easily distinguish these frequencies from background noise which occurs in the audible range of 20 Hz to 20 kHz.

6.)Holographic Detectors

Holographic gas sensors use light reflection to detect changes in a polymer film matrix containing a hologram. 

For this project i'm using electrochemical detectors by using MQ-4 sensor.