1. Performance

MQ-P5 gas sensors apply to the home and office device monitoring harmful gas, such as smoke, isobutane, formaldehyde.

2. Appearance and dimension

3. Technical specifications

4.Sensor Characterization

5. Notes:

1. Situations that must be avoided

1.1 Exposure to volatile silicon compound vapor

The sensor should avoid exposure to silicone adhesives, hair spray, silicone rubber, putty or other places where volatile silicon compounds exist. If the surface of the sensor is adsorbed with silicon compound vapor, the sensitive material of the sensor will be wrapped by silicon dioxide formed by the decomposition of the silicon compound, which will inhibit the sensitivity of the sensor and cannot be restored.

1.2 Highly corrosive environment

Sensors exposed to high concentrations of corrosive gases (such as H2S, SOX, Cl2, HCl, etc.) will not only cause corrosion or damage to the heating material and sensor leads, but also cause irreversible deterioration of the performance of sensitive materials.

1.3 Alkali, alkali metal salts, halogen pollution

Sensors contaminated by alkali metals, especially salt water spray, or exposed to halogens such as Freon will also cause performance deterioration.

1.4 Contact with water

Splashing or immersion in water will cause the sensitivity of the sensor to decrease.

1.5 Freezing

Water freezing on the surface of the sensor's sensitive material will cause the sensitive layer to break and lose its sensitive properties.

1.6 Excessive applied voltage

If the voltage applied to the sensor or heater is higher than the specified value, even if the sensor is not physically damaged or destroyed, it will cause damage to the lead or heater and cause the sensor's sensitive properties to decrease.

2. Situations to avoid as much as possible

2.1 Condensation

Under indoor conditions, slight condensation will have a slight effect on sensor performance. However, if water condenses on the surface of the sensitive layer and remains for a period of time, the sensor characteristics will decrease.

2.2 In high-concentration gas

Regardless of whether the sensor is powered on or not, long-term placement in high-concentration gas will affect the sensor characteristics. For example, if lighter gas is directly sprayed on the sensor, it will cause great damage to the sensor.

2.3 Long-term storage

When the sensor is stored for a long time without power, its resistance will have a reversible drift, which is related to the storage environment. The sensor should be stored in a sealed bag that does not contain volatile silicon compounds. Sensors that have been stored for a long time need to be powered on for a longer time before use to stabilize them.

The storage time and corresponding aging time recommendations are as follows:

2.4 Long-term exposure to extreme environments

Regardless of whether the sensor is powered on or not, long-term exposure to extreme conditions such as high humidity, high temperature or high pollution will seriously affect the performance of the sensor.

2.5 Vibration

Frequent and excessive vibration can cause the internal leads of the sensor to resonate and break. Such vibrations can be generated by using pneumatic screwdrivers/ultrasonic welders during transportation and on the assembly line.

2.6 Shock

If the sensor is subjected to strong shock or dropped, its leads will break.

2.7 Usage conditions:

2.7.1 Manual soldering is the most ideal soldering method for sensors. The recommended soldering conditions are as follows:

 Flux: Rosin flux with the least chlorine

 Constant temperature soldering iron

 Temperature: 250℃

 Time: no more than 3 seconds

2.7.2 The following conditions should be met when using wave soldering:

 Flux: Rosin flux with the least chlorine

 Speed: (1-2) m/min

 Preheating temperature: (100±20)℃

 Soldering temperature: (250±10)℃

 1 pass through the wave soldering machine

Violation of the above usage conditions will degrade the sensor characteristics.