Product Description:
1: Wide range of applications
2: Wide detection range
3: Fast response (less than 1s)
4: High sensitivity (3%)
5: long stable life
The MQ137 module is a sensor board designed to detect NH3 ammonia and other gases. The sensitive material of the MQ137 gas sensor is SnO2, which has low conductivity (high resistance) in clean air. When the target sensitive gas is present, the conductivity of the sensor increases with the gas concentration. The board comes with basic circuitry to change conductivity or voltage resistance and output it to header pins, DO and AO.
 
Feature:
Wide detection range
Fast response (less than 1s)
High sensitivity (3%)
Circuit voltage: DC5V
Stable and long life
Working voltage is +5V
Detect/Measure NH3, Ammonia
Concentration: 5-500ppm (ammonia)
Heater resistance (RH): 31Ω±3Ω at room temperature
Heater consumption (PH): ≤900mW
Sensing Resistance (Rs): 2KΩ-15KΩ (in 50ppm NH3)
Sensitivity (S): Rs(in air)/Rs(5000ppm CH4)≥5
Slope (α): ≤0.6 (R100ppm/R50ppm NH3)
Analog output voltage: 0V~5V
Digital output voltage: 0V or 5V (TTL logic)
Warm-up time: 20 seconds
Can be used as digital or analog sensor
Sensitivity of digital outputs can be adjusted using on-board potentiometers
TTL output valid signal is low level. (When the output is low, the signal light is on, which can be directly connected to the microcontroller or relay module)
The voltage of the analog output, the higher the concentration, the higher the voltage.
Working humidity: 95%RH (nominal humidity 65%RH)
Product size (mm): 35(L)*20(W)*28(H)
Weight: 17 grams
 
List:
1 x*MQ137 gas sensor module

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