MQ-8 Hydrogen sensor alarm module Gas sensors module 

MQ-8 Sensor Description:

MQ-8 gas sensor sensitive material used in clean air conductivity is lower tin dioxide (SnO2). When the sensor is present in the environment in which the combustible gas, the sensor's conductivity increases with the concentration of combustible gases in air increases. Using a simple circuit can be converted to the change in conductivity of the gas concentration with the corresponding output signal. MQ-8 hydrogen gas sensor of high sensitivity, the monitoring of the other hydrogen-containing gas is also very satisfactory. The sensor can detect a variety of hydrogen-containing gas, in particular, city gas, is a low-cost sensors for a variety of applications.

Module Applications:

Suitable for domestic or industrial hydrogen leak on a monitoring device. Are not subject to ethanol vapor, soot, carbon monoxide and other gases interference.

Module Features:

1, using high-quality dual-panel design, with power indicator and TTL signal output instructions;

2, with a DO switch signal (TTL) output and AO analog signal output;

3, TTL output valid signal is low. (When the output low signal light can be directly connected microcontroller or relay module)

4, the analog output voltage, the higher the concentration the higher the voltage.

5, the hydrogen gas detection with better sensitivity.

6, there are four screw holes for easy positioning;

7, Product Dimensions: 32 (L) * 20 (W) * 22 (H)

8, with a long service life and reliable stability

9, rapid response and recovery characteristics

Electrical properties:

Input voltage: DC5V power (current): 150mA

DO output: TTL digital 0 and 1 (0.1 and 5V)

AO output :0.1-0 .3 V (relatively clean), the highest concentration of voltage around 4V

Special note: The sensor is powered, needs to warm up around 20S, measured data becomes stable, the sensor fever is a normal phenomenon, because the internal heating wire, if hot is not normal.

Module using the instructions:

Explanation: Use Preheat 20S

The first step: to the module for 5V DC (note the positive and negative do not reverse, otherwise easily burned chip).

Step 2: If you select the output end of the high and low DO, TTL output signal can be connected directly to a microcontroller IO port or connect to the relay module, potentiometer is used to adjust the output level transition threshold.

Step Three: If you choose to AO, analog output, so you do not have control potentiometer AO feet directly connected to the input of the AD converter or microcontroller with AD can. According to our experience: In a normal environment, namely: the environment of the measured gas, setting the sensor output voltage value of the reference voltage, At this time, the voltage of the AO end about 1V, when the sensor detects that the gas to be measured when the voltage of each elevated 0.1V, the actual measured gas concentrations 200ppm (simple: 1ppm = 1mg/kg = 1mg / L = 1 × 10-6 commonly used to indicate the gas concentration, or the concentration of the solution.), on the basis of this parameter can microcontroller inside the measured analog voltage value is converted to concentration values. Note: If you are used to do a precision instrument, please buy the standard calibration instrument market, or there is an error, because the ratio of the output concentration and voltage relationship is linear, but tends to be linear.