Gas: Alcohol (ethanol)

Detection range: 10 ~ 1000ppm alcohol

Characteristic gas: 125ppm alcohol

Sensitivity: R in air/Rin typical gasge5

Sensitive body resistance: 1 ~ 20KOmega in air

Response time: le10s (70% Response)

Recovery time: le30s (70% Response)

Heating resistance: 31 Omega plusmn 3 Omega

Heating current: le180mA

Heating voltage: 5.0V plusmn 0.2V

Heating power: le900mW

Measuring voltage: le24V

Ambient temperature: -20 deg C ~ +55 deg C

Humidity: le95% RH

Environmental oxygen content: 21%

Storage temperature: -20 deg C ~ +70 deg C

Storage humidity: le70%RH

Product model: MQ135

Product Type: Semiconductor Gas Sensor

Detection gas: ammonia, sulfide, benzene vapor

Detection concentration: 10-1000ppm (ammonia, toluene, hydrogen)

Loop voltage (Vc): le24V DC

Heating voltage (VH): 5.0V plusmn 0.2V ACorDC

Load resistance (RL): adjustable

Heating resistance (RH): 31 Omega plusmn 3 Omega (room temperature)

Heating power consumption (PH): le900mW

Sensitive surface resistance (Rs): 2KOmega-20KOmega (in 100ppm NH3)

Sensitivity (S): Rs (in air) / Rs (100ppm NH3) ge 5

Concentration slope (alpha): le 0.6 (R100ppm/R50ppmNH3)

Temperature, humidity: 20 deg C plusmn 2 deg C; 65% plusmn 5% RH

Standard test circuit: Vc: 5.0V plusmn 0.1V; VH: 5.0V plusmn 0.1V

Warm-up time: no less than 48 hours

Connect VCC and GND and the module power indicator will light. Before use, the power supply is preheated for at least 2 minutes. It is normal for the sensor to heat slightly. Because there is a heating wire inside, it is not normal if it is hot.

When the module is not affected by the sensitive gas or the gas concentration does not exceed the set threshold, the digital interface DO port outputs a high level, and the analog interface A0 voltage is basically about 0v. When the gas influence exceeds the set threshold, the module digital interface D0 outputs low power. Flat, the digital indicator light is on, the voltage output from the analog interface A0 will gradually increase with the influence of gas, AO output: 0.1-0.3V (relatively non-polluting), the highest concentration voltage is about 4V;

Adjust the potentiometer clockwise (only for the sensitivity of the TTL output) to increase the concentration; the digital output D0 of the small board can be directly connected to the single-chip microcomputer, and the high-low level is detected by the single-chip microcomputer, thereby detecting the ambient gas; The quantity output DO can directly drive the relay module of the shop, thereby forming a gas switch;

The small board digital output DO can directly drive the store's active buzzer module, which can form a gas alarm; the small board analog output AO can be connected with the shop's AD module, and the approximate value of the ambient gas concentration can be obtained by AD conversion.