Datasheet MQ-2 (Winsen) - 6

Zhengzhou Winsen Electronics Technology Co., Ltd www.winsen-sensor.com The sensors performance wil be changed badly if sensors be sprayed pol uted by alkali metals salt especial y brine, or be exposed to halogen such as fluorine. 1.4 Touch water Sensitivity of the sensors wil be reduced when spattered or dipped in water. 1.5 Freezing Do avoid icing on sensor’s surface, otherwise sensing material wil be broken and lost sensitivity. 1.6 Applied higher voltage Applied voltage on sensor should not be higher than stipulated value, even if the sensor is not physical y damaged or broken, it causes down-line or heater damaged, and bring on sensors’ sensitivity characteristic changed badly. 1.7 Voltage on wrong pins For 6 pins sensor, Pin 2&5 is heating electrodes, Pin (1,3)/(4,6) are testing electrodes (Pin 1 connects with Pin 3, while Pin 4 connects with Pin 6).If apply voltage on Pin 1&3 or 4&6, it wil make lead broken; and no signal putout if apply on pins 2&4.
Fig8. Lead sketch 2 .Fol owing conditions must be avoided
2.1 Water Condensation Indoor conditions, slight water condensation wil influence sensors’ performance lightly. However, if water condensation on sensors surface and keep a certain period, sensors’ sensitive wil be decreased. 2.2 Used in high gas concentration No matter the sensor is electrified or not, if it is placed in high gas concentration for long time, sensors characteristic wil be affected. If lighter gas sprays the sensor, it wil cause extremely damage. 2.3 Long time storage The sensors resistance wil drift reversibly if it’s stored for long time without electrify, this drift is related with storage conditions. Sensors should be stored in airproof bag without volatile silicon compound. For the sensors with long time storage but no electrify, they need long galvanical aging time for stability before using. The suggested aging time as fol ow:
Stable2. Storage Time Suggested aging time
Less than one month No less than 48 hours 1 ~ 6 months No less than 72 hours More than six months No less than 168 hours 2.4 Long time exposed to adverse environment No matter the sensors electrified or not, if exposed to adverse environment for long time, such as high humidity, high temperature, or high pol ution etc., it wil influence the sensors’ performance badly. 2.5 Vibration Continual vibration wil result in sensors down-lead response then break. In transportation or assembling line, pneumatic screwdriver/ultrasonic welding machine can lead this vibration. 2.6 Concussion If sensors meet strong concussion, it may lead its lead wire disconnected. Tel: 86-371-67169097/67169670 Fax: 86-371-60932988 Email: sales@winsensor.com
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Document Outline Flammable Gas Sensor Instructions: The above fig is the basic test circ Resistance of Sensitive materials (Rs)=(Vc/VRL-1)× Power consumption of Sensitive materials (Ps)=Vc2×