wireless monitoring system of gas detector - Faculty of Electrical ...

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DC power
supply
Arduino
Board
Alarm
Indicator
Gas Sensor
LABVIEW
(GUI)
Figure 3.2: Block Circuit Diagram
As shown in Figure 3.2, the block diagram is about the connection of the gas
detector implementation. In this project, output voltage from the gas sensor will be
delivered to the Arduino board. The heart of the system is the Arduino board. All the
inputs and the outputs will be connected to the Arduino. When the gas sensor MQ6 or
MQ3 detect the presence of gas, it will send analogue signal to an analog digital
converter (ADC) inside the Arduino. An Arduino will process this signal and transfer to
the LABVIEW using zigbee. In the same time, Arduino also will analyze the signal
according the threshold value of gas concentration. The gas concentration value will
determine which LEDs will be lit up and if the red LED light up, this will also triggers
the buzzer to warn the users of gas concentration in the dangerous level. On the other
hand, as the yellow LED light up, this will also triggers the relay for switching on the
exhaust fan to suck out all the dangerous gas in the room and as the precaution before
dangerous level.