Product Overview MQ-137 Ammonia Gas NH3 Sensor Module The MQ137 sensor is a gas sensor module is specially designed to detect and sense gases like ammonia (NH3) and carbon monoxide (CO). Connect the MQ137 gas sensor module’s digital pins to a microcontroller like Arduino boards. This setup helps you detect a specific gas. Features of MQ-137 Ammonia Gas NH3 Sensor Module Wide detecting scope Fast response (less than 1s) High sensitivity( 3%) the circuit voltage: DC5V Stable and long life Analog output voltage: 0V to 5V Digital output voltage: 0V or 5V (TTL Logic) Use it as a digital or analog sensor Adjust the sensitivity of the digital output using an onboard potentiometer The TTL output valid signal is low. (When the output is low, the signal light is on, it can be directly connected to the MCU or relay module) The voltage of the analog output, the higher the concentration, the higher the voltage. Arduino compatible How to detect gases with the MQ-137 gas sensor module? Power the gas sensor module with 5V and you should notice the power LED on the module glow. When the sensor detects no gas, the output LED stays off, and the digital output pin remains at 0V. Preheat these sensors before using them. Introduce the sensor to the gas you want to detect and you should see the output LED go high along with the digital pin, if not use the potentiometer until the output gets high. Applications of MQ137 Gas Sensor Detector measure Gases like NH3 or CO Air quality monitor Gas leak alarm Safety standard maintenance Maintaining environmental standards  in hospitals Click here to buy other Sensors Click here for more info SKU: A-6/3 Category: SENSORS