The aim of this project is to build an advanced gas leakage detection and monitoring system based on Microchip PIC 16F877A microcontroller. This is an 8-bit microcontroller. Besides this microcontroller, we require an LPG gas sensor, load sensor, buzzer, power supply, and relay to build the complete project.
The load sensor senses the weight of the gas cylinder and gives the result in kilograms. This is interfaced using the USART (serial communication interface) of the PIC16F877A microcontroller. From the current total weight of the gas cylinder in kilograms, we are calculating the percentage of LPG gas remaining in the cylinder and display it on attached to the microcontroller. For the percentage calculation, we know the weight of the empty cylinder printed on the gas cylinder itself and also the total weight is printed on it. From these two values, we can calculate the amount of gas remaining by subtracting the weight of empty cylinder from the total weight. This can be converted to percent and displayed on LCD. At the same time, an LPG sensor module is used to detect any gas leakage and it is interfaced to the microcontroller using the digital port pin and if there is gas leakage detected, the output signal from the LPG sensor module changes and it is sensed by the microcontroller to display it on LCD as well as give an audio alert using the buzzer attached to the microcontroller. If there is a gas leakage, then the household ac power supply can be disconnected using a relay. If there is no gas leakage detected, the ac power supply is not disconnected. The programming for the microcontroller is done using embedded c using the MPLABX IDE and XC8 compiler. The circuit can be powered using a power supply unit consisting of an LM7805 regulator IC which gives a regulated output of 5v DC. The input to the regulator
is a 9v DC adapter.
1. LOADCELL 80K
2. LPG SENSOR MODULE