Working Principle:

1. Photoionization sensor (PID) technology:

This is a commonly used technology for portable TVOC detectors. By irradiating with ultraviolet light, volatile organic compound molecules are ionized to generate photoelectric signals.

The photoelectric signal outputs a voltage signal through an operational amplifier, and the magnitude of the voltage signal is proportional to the gas concentration value.

The voltage signal is compared by an integrated circuit processor to generate a digital signal, which is displayed in real-time on the instrument screen.

2. Chemical sensor technology:

Using a set of sensors to accurately measure indoor harmful chemical gases based on chemical reaction principles.

When TVOC or other harmful gases in the environment enter the instrument, they react chemically with specific reagents present in the sensor, forming an electrical signal.

The electrical signal changes with the concentration of harmful gases, is collected by the instrument and transmitted to the built-in microprocessor for processing, and then converted into display values.

Portable TVOC gas detectorMain parameters:

1. Detection range: commonly 0-10ppm, 0-100ppm, or 0-1000ppm.

2. Resolution: * Small identifiable concentration changes (such as 0.001ppm, 0.01ppm), the higher the resolution, the more accurate the detection.

3. Response time: The time from contact with gas to displaying stable values is usually less than 10 seconds for PID sensors and slightly slower for MOS sensors.

4. Accuracy: The deviation between the measured value and the true value, usually ± 5% FS (full scale) or ± 10% reading.

5. Working environment: Temperature and humidity, exceeding the range may affect accuracy.