HANWEI ELECTRONICS CO.
,LTD
MQ-136
http://www.hwsensor.com
TECHNICAL DATA
MQ-136 GAS SENSOR
FEATURES Fast response and High sensitivity Stable and long life Simple drive circuit APPLICATION They are used in air quality control equipments for buildings/offices, are suitable for detecting of H2 S. SPECIFICATIONS A. Standard work condition
Symbol Vc VH RL RH PH Symbol Tao Tas RH O2 Parameter name Circuit voltage Heating voltage Load resistance Heater resistance Heating consumption Technical condition 5V0.1 5V0.1 can adjust 315% less than 800mw Technical condition -10-45 -20-70 less than 95%Rh 21%(standard condition)Oxygen concentration can affect sensitivity Technical parameter 30K-200K (10ppm H2S ) 0.65 Vc:5V0.1 Vh: 5V0.1 Remarks AC OR DC ACOR DC Room Tem
B. Environment
condition
Remarks
Parameter name Using Tem Storage Tem Related humidity Oxygen concentration
minimum value is over 2% Ramark 2 Detecting concentration scope 1-100ppm H2S
C. Sensitivity characteristic
Symbol Rs Parameter name Sensing Resistance Concentration Slope rate Temp: 202 Humidity: 65%5%
(20/5) H2S Standard Detecting Condition Preheat time
Over 24 hour
D. Structure and configuration, basic measuring circuit
1 2 3 4 5 6 7 8 9
Parts Gas sensing layer Electrode Electrode line Heater coil Tubular ceramic Anti-explosion network Clamp ring Resin base Tube Pin
Materials SnO2 Au Pt Ni-Cr alloy Al2 O3 Stainless steel gauze (SUS316 100-mesh) Copper plating Ni Bakelite Copper plating Ni
Fig. 1
Configuration A Configuration B
Fig.2
Structure and configuration of MQ-136 gas sensor is show n as Fig. 1 (Configuration A or B), sensor composed by micro AL 2O3 ceramic tube, Tin Dioxide (SnO2) sensitive layer, measuring electrode and heater are fixed into a crust made by plastic and stainless steel net. The heater provides necessary work conditions for work of
TEL: 86-371-5333098 5333099 FAX: 86-371-5333090 E -mail: sensor@371.net
HANWEI ELECTRONICS CO.,LTD
MQ-136
http://www.hwsensor.com
sensitive components. The enveloped MQ-136 have 6 pin ,4 of them are used to fetch signals, and other 2 are used for providing heating current. Electric parameter measurement circuit is show n as Fig.2
E. Sensitivity characteristic curve
Fig.3 is shows the typical sensitivity characteristics of the MQ-136 for several gases.
in their: Temp: 20 Humidity: 65% O2 concentration 21% RL=20k Ro: sensor resistance at 10ppm of H2S in the clean air. Rs: sensor resistance at various concentrations of gases.
Fig.3 sensitivity characteristics of the MQ-136
Fig.4 is shows the typical dependence of the MQ-136 on temperature and humidity.
Ro: sensor resistance at 10ppm of H2S at 33%RH and 20 degree. Rs: sensor resistance at 10ppm of H2S at different temperatures and humidity.
Fig.4
SENSITVITY ADJUSTMENT Resistance value of MQ-136 is difference to various kinds and various concentration gases. So, When using this components, sensitivity adjustment is very necessary. we recommend that you calibrate the detector for 10ppm H2 S concentration in air and use value of Load resistance that( RL ) about 20 K(10K to 47 K). When accurately measuring, the proper alarm point for the gas detector should be determined after considering the temperature and humidity influence.
TEL: 86-371-65333098 65333099 FAX: 86-371-65333090
E -mail: sensor@371.net
