welcome to our keyhole, we provide you various knowledge from various sources such as Electric&Electronic, Health, Arduino, IOT, Diy projects, A/l past paper and model paper, Even though you can keep in touch with current technology
In this example, you will read the sensor analog output voltage and
when the smoke reaches a certain level, it will make sound a buzzer and a
red LED will turn on. When the output voltage is below that level, a green LED will be on.
What is an MQ-2 Smoke Sensor
MQ2 gas sensor
can be used to detect the presence of LPG, Propane and Hydrogen, also
could be used to detect Methane and other combustible steam, it is with
low cost and suitable for different application. Sensor
is sensitive to flammable gas and smoke. Smoke sensor is given 5 volt
to power it. Smoke sensor indicate smoke by the voltage that it outputs
.More smoke more output. A potentiometer is provided to adjust the
sensitivity. Sn02 is the sensor used which is of low conductivity when
the air is clean. But when smoke exist, an analog output is produced
based on the concentration of smoke. The circuit has a heater. Power is
given to heater by VCC and GND from power supply. The circuit has a
variable resistor. The resistance across the pin depends on the smoke in
air in the sensor. The resistance will be lowered if the content is
more. And voltage is increased between the sensor and load resistor.
How does it Work?
The
voltage that the sensor outputs changes accordingly to the smoke/gas
level that exists in the atmosphere. The sensor outputs a voltage that
is proportional to the concentration of smoke/gas. In other words, the relationship between voltage and gas concentration is the following:
The greaterthe gas concentration,the greaterthe output voltage
The lowerthe gas concentration,the lowerthe output voltage
Pin Wiring
The MQ-2 sensor has 4 pins.
Pin--Wiring to Arduino Uno
A0---Analog pins
D0----Digital pins
GND-----GND
VCC--------5V
No comments:
Post a Comment