Gas Level Detection and Leakage Monitoring System using a specific Technique I. Juvanna 1 , N. Meenakshi 2 1. Asst.Professor, Hindustan Institute of Technology and Science, Padur, Chennai 2. Asst.Professor, Hindustan Institute of Technology and Science, Padur, Chennai juvanna@gmail.com , abu221985@gmail.com ABSTRACT Liquified Petroleum gas (LPG) is the common one for all cooking applications. Most of us are prone to much difficulty when the gas cylinder gets emptied during the peak cooking hours. We present this paper in order to create awareness about the decreasing weight due to consumption of the gas and to automatically dial to the gas booking office. Continuous measurement of the weight cannot be done using electronic weight gauges, since it causes fatigue in the springs. Hence we move to contact less detection involving acoustic wave. In this system, the inbuilt pressure sensor in RFID is used to measure the level of the gas inside the cylinder. The output of the pressure sensor is given to the PIC controller, where the voltage corresponding to the gas weight is stored. The same is displayed in the LCD, which is connected to the output port of the controller. A threshold value is set in the controller. Once the threshold level is reached, the voltage value is given to the alarm, which alarms the user. And also it is given to the autodialler.A special sensor for detecting the gas detection agent is inbuilt in the RFID device,whose output is connected to the alarm. KEYWORDS: 1-RFID, 2-Pressure sensor, 3-Auto Dialing, 4-Gas detection agent 1. INTRODUCTION Liquified petroleum gas has a world wide application. It has a wide domestic usage in cooking and for heating. We are put into much difficulty when the cylinder runs out of gas. Hence it is necessary in the busy world, to detect the decrease in weight of the gas cylinder. It is made possible by using inbuilt pressure sensor in RFID device. The output is fed to a controller which has input ports, output ports and I/O ports. It is 18 pin IC of package. Its special feature is it operates in three modules 1.capture, 2.compare, 3. PWM. It operates at a voltage range of 3.0V to 5.5V. LCD is connected to one of the ports, for displaying the voltage. Controller is programmed in such a manner that it creates an alarm when the voltage is equal to the threshold value. An auto dialer is enabled for booking the gas cylinder. Also when there is a gas leak from the cylinder, the sensor detects it and alarms the user. 2. THEORY The direct cylinder pressure monitoring system (CPMS) refers to the use of pressure sensor directly mounted on the transport cap of the cylinder. The pressure inside the cylinder is measured continuously by the pressure sensor and the information will be continuously sent to the system using the radio frequency technology [1] . Fig.1.Gas cylinder with RFID Device In the Fig.1….The cylinder has two outlets, in one of the opening the sensor with the RFID is attached and the another valve is used for connection. The initial level of the pressure is noted and saved in the system and using the LCD We can continuously monitor the level of the pressure inside the cylinder. 2.1.Working Principle of the system The pressure inside the cylinder will be sensed by the sensor and it will be communicated to the PIC controller and the LCD using the RFID tag in the cylindrical valve. The output of the pressure sensor is analog signal, which when striking the cylindrical surface produces the electromagnetic wave [2] . This EM wave is sensed by the RFID and it is communicated to the controller. Once the pressure reaches the threshold value the controller sends the message to the auto dialler.