NDIR Infrared CH4 Gas Sensor （Model：MH-440D） Zhengzhou Winsen Electronics Technology Co.,

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Zhengzhou Winsen Electronics Technology Co., Ltd. MH-440D NDIR Infrared CH4 Sensor 1. Introduction MH-440D infrared gas sensor is a miniature universal intelligent sensor, which adopts NDIR theory to detect concentration of CH4 in air and has good selectivity, stable performance, long life, also is independent of Oxygen. The inside temperature sensor could be used for temperature compensation. This miniature infrared gas sensor is developed by the tight integration of mature infrared absorbing gas detection technology, micro machine workout and superior circuit design. It is convenient in use...

Zhengzhou Winsen Electronics Technology Co., Ltd. Fig2.Measuring Range and Resolution Target Gas Molecular Formula Measuring Range Temperature compensation UART（RXD） 0～3.0 V data input UART（TXD） 0～3.0 V data output 6.Output way. 6.1 Analog Output The output of Vout is proportional to the gas concentration, 0.4-2.0V output stands for 0 to full range. Connection: Vin –5V, GND- Power Ground, Vout-ADC input. After warm-up, Vout will show the voltage standing for the gas concentration. If self-checking detects a fault, the output voltage is 0V. Output concentration = sensor range * output voltage...

Zhengzhou Winsen Electronics Technology Co., Ltd. www.winsen-sensor.com Intrinsically safe explosion-proof ➢ This product meets the standards of GB3836.1-2010 "Explosive Atmosphere Part 1: General Requirements for Equipment" and GB3836.4-2010 "Explosive Atmosphere Part 4: Equipment Protected by Intrinsically Safe "i"" standards”; the explosion-proof mark is Exib ⅡB T4 Gb, it is suitable for zone 1 and zone 2, contains Class IIA, T1-T3 explosive environment formed by the flammable gas, mixture of steam and air; it has passed the inspection by the National Quality Inspection Center for Explosion-proof...

Zhengzhou Winsen Electronics Technology Co., Ltd. Li: Maximum internal inductance of the sensor Lc: Maximum allowable distributed inductance of connecting cable. 7. Cautions for Maintenance 7.1 The sensor should be calibrated regularly. The suggested cycle time is 6 months. 7.2 Do not use the sensor in the high dusty environment for long time. 7.3 Please use the sensor with correct power supply. 7.4 Forbid to weld the sensor pins directly. 7.5 Forbid to cut the sensor pins. Output concentration = sensor range * output voltage (V) / (2 - 0.4). Output concentration = sensor range * output voltage...