5.Sensor Characterization

6.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 can 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 the lead wire to protrude and/or the heater to be damaged, and cause the sensor's sensitive properties to decrease.

2. Situations to avoid as much as possible

2.1 Condensation

Under indoor use 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, using lighter gas to spray directly on the sensor 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.