Infrared detector principle features and installation notes (1)

Infrared detector is a security alarm system in the most critical component of a decision directly sensitivity and stability of the system, the entire system of quality assurance.

China security vendor in these years, mastery of both technology and production capacity enhancement, improved significantly, due to Chinese manufacturers constantly absorbing foreign product design and production technology, and is committed to lower costs, allow Chinese security products begin to get the project developers ' identity, plus the price for the party has important attraction, introduced in the market to grow rapidly. Although introduced quality still and imported products have a gap, but users are not familiar with the security products, security products are still very competitive.

Many foreign manufacturers also acknowledged that the previous foreign technical advantages to substantially relies on China might cost advantage, but the gap has narrowed in recent years, the advantage of decreasing, visible Chinese companies in the technology are gradually catching up with foreign manufacturers, parts manufacturers more innovation capacity, the introduction of distinctive products, the level of China's security products.

This phenomenon mainly from many manufacturers for brand awareness and product quality, increased investment and research and development efforts.

Infrared detector principle and characteristics

The human body has a constant temperature, usually in the 37 degrees, will issue a specific wavelength 10 μ m or so of infrared, passive infrared detector is relying on detection of human emissions of 10 μ m around the work of infrared.

Human emission of 10 μ m or so infrared through Fresnel filter enhancements after aggregation to infrared sensors on the source. Infrared induction source usually Pyroelectric component, this component in the received human infrared radiation temperature change will lose its charge balance, release charge, subsequent circuit tested treatment can produce a warning signal.

1. passive infrared detectors is to target the human radiation surveying, Pyroelectric element on the wavelength is 10 μ m or so of infrared radiation must be very sensitive.

2. in order to only on body of infrared radiation sensitive, its radiation is usually covered with special Fresnel filter, enable environmental interference control function is obvious.

3. the sensor contains two serial or parallel connection of Pyroelectric element.

But the two electrodes in the opposite direction, environmental background radiation on two Thermo elements almost have the same effect, so that it produces Pyroelectric effect offset each other, so the probe no signal output.

4. once the people within the region intrusion detection infrared radiation through the body part focusing mirror, and was receiving Pyroelectric element, but the two slices of Pyroelectric element received heat, Pyroelectric different cannot offset, signal processing and alarm.

Passive infrared deep sokki advantages and disadvantages

Advantages: does not send any type of radiation, device power consumption is very small, invisibility, low price.

Disadvantages: vulnerable to various sources of heat, the sunshine jamming; passive infrared penetration is low, the body of the infrared radiation can easily be obscured, not detector receive; susceptible to interference of radio frequency radiation; environmental temperature and the temperature close to the human body, the noticeable decline in detection and sensitivity, sometimes resulting in short-time failure.

How to properly install and use the passive infrared detector

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