MQ138

MQ138 Semiconductor Sensor for Organic Steam Sensitive material of MQ138 gas sensor is SnO2, which with lower conductivity in clean air. When the target Organic Steam exist, The sensor’s conductivity is more higher along with the gas concentration rising. Please use simple electrocircuit, Convert change of conductivity to correspond output signal of gas concentration. MQ138 gas sensor has high sensitity to Toluene, Acetone, Ethanol and Formaldehyde, also to other organic steam. The sensor could be used to detect different organic steam, it is with low cost and suitable for different application. Character * Good sensitivity to Organic Steam * High sensitivity to Toluene, Acetone and Ethanol * Long life and low cost * Simple drive circuit Configuration Application * Domestic Organic steam detector * Industrial Organic steam detector * Portable gas detector Technical Data Basic test loop Model No. MQ138 Vc VRL Sensor Type Semiconductor Standard Encapsulation Bakelite (Black Bakelite) Detection Gas Toluene, Acetone, Ethanol, H2 Concentration 5-500ppm Circuit Loop Voltage Heater Voltage Load Resistance Vc VH RL ≤24V DC 5.0V±0.2V AC or DC Adjustable Heater Resistance RH 31Ω±3Ω（Room Tem.） Character Heater consumption Sensing Resistance PH ≤900mW Rs 2KΩ-20KΩ(in 50ppm Toluene ) Sensitivity S Rs(in air)/Rs(50ppm Toluene)≥3 Slope α ≤0.6≤0.6(R100ppm/R50ppm Toluene) Tem. Humidity 20℃±2℃；65%±5%RH Condition Standard test circuit Vc: 5.0V±0.1V； VH: 5.0V±0....