MQ-137 Ammonia Gas Sensor Module

The gas sensing material used in the MQ137 gas sensor is tin dioxide (SnO 2 ) which has a low conductivity in clean air . When ammonia is present in the environment in which the sensor is located, the conductivity of the sensor increases as the concentration of ammonia in the air increases. The change in conductivity can be converted to an output signal corresponding to the gas concentration using a simple circuit. The MQ137 gas sensor is highly sensitive to ammonia and is ideal for monitoring other organic amines such as trimethylamine and ethanolamine. This sensor detects a wide range of ammonia-containing gases and is a low-cost sensor for a wide range of applications.

1. It adopts high quality double panel design with power indication and TTL signal output indication;

2. It has DO switch signal (TTL) output and AO analog signal output;
3. TTL output high and low level. (Can be directly connected to the MCU or relay module)
4. The analog output voltage changes with the concentration.
5. Good sensitivity to liquefied gas, natural gas, city gas, and smoke.
6, there is a screw hole for easy positioning;
7, has a long service life and reliable stability
8, fast response recovery characteristics
electrical performance:
input voltage: DC5V power consumption (current): 150mA
DO output: TTL digital quantity 0 And 1 (0.1 and 5V)
AO output: analog level signal
special reminder: after the sensor is energized, it needs to preheat about 20S, the measured data is stable, the sensor heating is normal, because there is electric heating wire inside, if it is hot, it is not normal. It is.
Wiring method:
1. VCC: Connect the positive pole of the power supply (5V)
2. GND: Connect the negative pole of the power supply
3. DO: TTL switch signal output
4. AO: Analog signal output
5, with fixed bolt holes for easy installation