1. Description

MQ-E3-SO2 is the sensor of fixed potential electrolysis type. By redox reaction, SO2 and O₂release charge and form the current. The value of current is proportional to the concentration of SO2 and follow the Faraday’s Law. By testing the value of current, the concentration of SO2 is known.

2. Application

Widely used in industry or environmental protection field for detecting SO2.

3. Appearance and dimension

4. Technical specifications

5.Basic Circuit

6.Test Circuit

7.Sensor Characterization

8.Precautions

 Soldering is prohibited during installation;

 Pins must not be broken or bent;

 Aging time should be no less than 48 hours before use;

 Electrolyte leakage may cause damage, so please do not disassemble the sensor at will;

 Sensors should avoid contact with organic solvents (including silicone rubber and other adhesives), paints, pharmaceuticals, fuel oils and high concentrations;

 All electrochemical sensors should not be completely encapsulated with resin materials, nor should they be immersed in an oxygen-free environment for a long time, otherwise the performance of the sensor will be damaged;

 All electrochemical sensors should not be used in an environment containing corrosive gases for a long time, as corrosive gases can damage the sensor;

 When measuring the zero point of gas, it must be done in a clean atmosphere;

 When testing and applying the sensor, vertical air intake from the front must be avoided;

 The air intake surface of the sensor must not be blocked or contaminated;

 The waterproof and breathable membrane above the sensor must not be opened or removed;

 The sensor should not be subjected to excessive impact or vibration;

 Do not use it if the shell is damaged or deformed;

 After long-term use in a high-concentration gas environment, it is slow to recover to the initial state;

 When storing the sensor, the working electrode and the reference electrode should be in a short-circuit state;

 It is forbidden to encapsulate the sensor with hot melt adhesive or sealant with a curing temperature above 80℃;

 It is forbidden to store and use the sensor in high-concentration alkaline gas for a long time.