The basic principle of PID is to use the ultraviolet (VUV) generated by the vacuum discharge phenomenon of inert gas to ionize the gas molecules to be measured, and to obtain the concentration of the gas to be measured by measuring the current intensity generated by the ionized gas.
The photoionization (PID) detection method has the following advantages: (1) High precision, which can meet the quantitative detection of low-concentration benzene (2) Strong anti-interference, the common gas (alkane) in the petrochemical industry is not easy to affect it; (3) With pump-suction air intake, it has quick response and quick recovery; (4) It is a non-destructive detector, it will not "burn" or permanently change the gas to be measured.
However, Lion's environmental PID product series not only have the above common advantages, but also the following four points:
Advantage 1: Using patented vacuum ceramic tube ionization PID lamp
Using the latest generation of photoion technology, it has a life span and detection accuracy that far exceed the previous generation of products (PID lamp 18 months warranty). Compared with the industry's average PID lamp warranty period of 6-8 months, it has significant technical advantages and a higher overall cost performance.
Advantage 2: Patented dual-channel air supply, with automatic cleaning and automatic zero adjustment functions
Patented dual-airway air intake system, combined with a special filter device, can realize automatic cleaning and automatic zero adjustment functions. It has super strong ability to resist harsh environments (high humidity, dust), while ensuring detection accuracy and reducing on-site maintenance workload.
Advantage 3: Built-in long-life diaphragm pump, sensitive detection and quick response
1. Diffusion detection
Advantages: relatively low cost
2. Pump suction test
Advantages:
① Inhalation detection, sensitive detection and rapid response (T90<20S);
② The organic vapor is drawn into the ion chamber and discharged immediately after being detected, and will not be ionized in the ion chamber; it prolongs the life of the detector and the recovery time is short (less than 20S);
③ The sensor and ion chamber have built-in explosion-proof shells to avoid the interference of high humidity and dust, and the failure rate is low;
④ With the patented dual-airway design, it can realize the functions of automatic cleaning and automatic zero adjustment, with good long-term stability.
Disadvantages: relatively high cost.
Advantage 4: Built-in temperature and humidity compensation function
Built-in temperature and humidity sensor, automatically correct the measurement deviation caused by temperature and humidity. Ensure the same high measurement accuracy under various environmental conditions.
Advantage 5: Using dot matrix LCD screen, Chinese menu
The large-size LCD screen with 128x64 dot matrix can display abundant instrument operation and operation information (including storing alarm records, querying data such as TWA and STEL). It adopts Chinese menu and friendly man-machine interface design, which is convenient for users to operate and maintain.
