How do tvoc Sensors Work?
The TVOC detector is a common gas detector. The tvoc sensor is the core equipment in the detector. The application in the industrial field is relatively wide. When we use a instrument, we should know how it is how it is how it is The work can be used in what areas it can be applied to ensure that the instruments we choose meet the requirements of usage, so what are the working principles and applications of the TVOC detector.
What is VOC?
According to the definition of the World Health Organization, if at 101.32kPa, the boiling point of the compound is at 50 ° C-250 ° C, which is volatile organic matter. They exist in the form of gas at room temperature. According to the different chemical structure, it can be further divided into eight class: alkane, aromatics, olene, halogen hydrocarbons, esters, aldehyde, ketones and other. The main components of VOC are: hydrocarbons, halogen, hydrocarbons, oxygen and nitrogen, which include: benzene, organic chloride, fluoron series, organic ketone, amine, alcohol, ether, ester, acid and petroleum hydrocarbon compounds wait.
For example, formaldehyde, which is volatile from paint and furniture, its boiling point is only -19 ° C.
At present, the sensor of TVOC mainly includes PID -based optical quantum sensors and semiconductor sensors based on metal oxides.
How do tvoc Sensors Work?
PID tvoc sensor:
PID tvoc sensor working principle
PID uses an ultraviolet light (UV) light source to ionize organic molecular ion (ionization) that can be detected by detectors. The detector capture the positive and negative charges of ionized gas to transform it into a current signal to measure the gas concentration. When the gas absorbs high -energy ultraviolet light to be measured, the gas molecules are temporarily lost by the inspiration of ultraviolet light to become ions with positive charge. After the gas ion is detected on the electrode of the detector, the electrons will soon form the original gas and steam molecules. PID is a non -broken detector that does not change the gas molecules to measure the gas. Gas detected by PID can still be collected for further measurement.
Features: fast response, many detection gas, simple design, easy maintenance
Semiconductor principle tvoc sensor
When this type of sensor detects the measured gas, its conductivity will change accordingly. With the increase and decrease of the concentration of the measured gas, the conductivity will increase and decrease. After the circuit outputs the information, the detection value of the tvoc can be obtained.
Advantages: cheap and long life
Disadvantages: Poor consistency, poor stability, slow response time, and less VOC gas types that can be detected.
TVOC Sensors application field
The scope of use of TVoc Sensor in practical applications is very wide. Basically, it can be detected in the field of volatile gases. It is commonly used in tvoc Sensor. In the field. The TVOC detector can accurately measure a variety of volatile organic gas concentrations such as benzene, formaldehyde, formaldehyde, styrene, toluene, acetone, octane, and pentane.