MQ137 Ammonia (NH3) gas sensor belongs to the MQ gas sensor series known for their effective and quick response in the detection of dangerous concentrations of harmful gases. The module is also capable of detecting traces of Carbon monoxide (CO) gas, adding to its design versatility. MQ137 is highly sensitive to Ammonia gas (NH3) and can be used to detect any leaks or presence of ammonia in the air. MQ137 gas sensor can detect ammonia gas concentrations anywhere from 5-200ppm (parts per million).
The sensor has a high sensitivity to Ammonia gas and a fast trigger response time correlative to the detection interval. The sensor’s output is analog resistance corresponding to the concentration of Ammonia gas (NH3) in the vicinity. The drive circuit is very simple; all that is required to do is to power up the heater coil with 5V, add a load resistance, and connect the output to an ADC (analog to digital converter). MQ137 gas sensor is low cost and is suitable for all kinds of different applications for detecting poisonous concentrations of Ammonia (NH3) gas. The module is highly adaptive to changes in atmospheric conditions and can be easily interfaced with any MCU (Arduino, NodeMCU) to identify, detect, and monitor harmful concentrations of Ammonia Gas in its immediate surroundings.
MQ137 Gas Sensor Key Features
- Preheat duration over 24 hours
- Can be used as a Digital or analog sensor
- The Sensitivity of the Digital pin can be varied using a potentiometer
- Analog output is continuous
- Compact size
- Less cost
- ESD Protection
- Overvoltage Protection
- Dual signal output
- Quick response
- Reliable and long service life
MQ137 Gas Pinout
| Pin Name | Pin No. | Description |
|---|---|---|
| VCC | 1 | This pin powers the module, typically the operating voltage is +5V |
| GND | 4 | Used to connect the module to the system ground |
| DO | 2 | You can also use this sensor to get digital output from this pin, by setting a threshold value using the potentiometer |
| AO | 3 | This pin outputs 0-5V analog voltage based on the intensity of the gas. |
Specifications
- Circuit voltage: 5V±0.1
- Heating voltage: 5V±0.1
- Load resistance: Adjustable
- Heater resistance: 31Ω ±5%
- Heating consumption: less than 800mw
- Using Temperature: -10℃-45℃
- Storage Temp: -20℃-70℃
- Related humidity: less than 95%Rh
- Sensing Resistance: 900KΩ-4900KΩ (in the air)
Applications
- They are used in air quality control equipment for buildings/factories and are suitable for detecting traces of NH3.
Datasheet
You can download the datasheet for MQ137 Ammonia Gas Sensor Module by clicking the link given below:
See Also: SIM900A Dual Band GSM/GPRS Module | DS3231 Precision I2C Real-Time Clock Module | MT8870D Integrated ISO2-CMOS DTMF Receiver Module
