MQ7 MQ 7 MQ-7 Smoke Liquefied Flammable Methane Gas Sensor Module for Arduino Diy Starter Kit

   MQ-7 gas sensor is sensitive material used in clean air, low conductivity tin dioxide (SnO2). Detection method using low temperature cycling (1.5V heating) detect carbon monoxide, airborne sensor conductivity increases with the increase of the concentration of carbon monoxide gas, high temperature (5.0V heating) cleaning stray gas adsorption at low temperature. Using a simple circuit can be changes in the conductivity, concentration of the gas is converted to the corresponding output signal. MQ-7 gas sensor with high sensitivity for carbon monoxide, this sensor can detect a variety of gases containing carbon monoxide, is a low-cost sensors for a variety of applications .

   Gas may be used in homes and factories leakage monitoring device suitable for the detection of gas, butane , propane , methane , smoke , etc. ;

• Using high-quality dual-panel design, with power indicator and TTL signal output instructions;
• The switching signal having a DO (TTL) output and analog output AO ;
• TTL output valid signal is low . ( Low-level signal when the output light can be directly connected to the microcontroller or relay module )
• Analog output voltage with the higher concentration of higher voltage.
• A gas, natural gas, city gas , smoke better sensitivity.
• There are four screw holes for easy positioning ;
• Has a long life and reliable stability
• Rapid response and recovery characteristics

• Input voltage : DC5V Power consumption ( current ): 150mA
• DO output : TTL digital 0 and 1 ( 0.1 and 5V)
• AO output :0.1-0 .3 V ( relative to pollution ) , the maximum concentration of a voltage of about 4V
• Special note: After the sensor is powered , needs to warm up around 20S, measured data was stable , heat sensor is a normal phenomenon , because the internal heating wire , if hot is not normal .

• VCC: positive power supply (5V)
• GND: power supply is negative
• DO: TTL switching signal output
• AO: analog signal output