5pcs MQ137 Ammonia Sensor Module MQ-137 NH3 Gas For Detection Leak Alarm | Электронные компоненты и

5pcs MQ137 Ammonia Sensor Module MQ-137 NH3 Gas For Detection Leak Alarm | Электронные компоненты и

Product description:The gas sensing material used in the MQ137 gas sensor is tin dioxide (SnO2) with lower 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. Features:This product has good sensitivity to ammonia in a wide concentration range, and has the advantages of long life, low cost, and simple driving circuit.application:Widely used in household ammonia alarms, industrial ammonia leak alarms and portable ammonia detectors. Parameter:

• Product Type: Semiconductor Gas Sensor

• Standard package: bakelite, metal cover

• Detection gas: ammonia

• Detection concentration: 5 ~ 500ppm ammonia

• Loop voltage Vc: ≤24V DC

• Heating voltage VH : 5.0V ± 0.1V AC or DC

• Load resistance RL: adjustable

• Heating resistance RH : 29 Ω ± 3 Ω (room temperature)

• Heating power consumption PH : ≤900mW

• Sensitivity S : Rs (in air) / Rs (50ppm NH3) ≥ 2

• Output voltage △Vs: ≥0.5V (in 50ppm NH3)

• Concentration slope α : ≤ 0.6 (R200ppm / R50ppm NH3)

• Temperature, humidity: 20 °C ± 2 °C; 55% ± 5% RH

• Standard test circuit: Vc: 5.0V ± 0.1V; VH: 5.0V ± 0.1V

• Warm-up time: no less than 48 hours

• Oxygen content: 21% (not less than 18%, (oxygen concentration will affect the initial value, sensitivity and repeatability of the sensor, please consult when using at low oxygen concentration)

• Life expectancy: 5 years

Note: The figure above shows the basic test circuit for the MQ137 sensor. The sensor requires two voltages to be applied: heater voltage (VH) and test voltage (VC). The VH is used to provide a specific operating temperature for the sensor, either DC or AC. The VRL is the voltage across the load resistor (RL) of the sensor in series. VC is the voltage for testing the load resistor RL and requires a DC power supply.