Design of Ignitable Gas Alarm Detector and Controller
Based on MCU
Abstract
The system consists of MQ-2 sensor, the single chip microcomputer
AT89C51 analog to digital converter chip, the ADC0804, the LCD1602. Its
function is to monitor the concentration of combustible gases in the
environment, when the concentration reaches the alarm set value, the system
will trigger sound and light alarm. The system is divided into hardware and
software. Hardware consist of the acquisition circuit of the gas concentration,
the A / D conversion circuit, the smallest system of AT89C51, circuit,
display circuit, the alarm circuit and the key circuit. When the system is
working, the signal acquisition circuit convert the gas concentration to
analog voltage, then the analog voltage is converted by ADC converter
device to digital signal and then send into the microcontroller, The cpu
establish the relationship between concentration and voltage, then the result
is dispiayed by 1602LCD .If the combustible gas concentration reaches the
alarm set value, the system will trigger sound and light alarm, at the same
time RF transceiver /receiver module touches the valve to open the exhaust
fan.When an unknown risk happen, the system can also control to open the
function of manually alarm and manually cancel the alarm. The
programming is implemented by KEIL C51, and the system is simulated by
PROTEUS. System achieved the desired function.
Key word: MQ-2 sensor
；
AT89C51
；
ADC0804
；
LCD
；
RF transceiver /
receiver module
