LED lighting and lighting the biggest difference between the traditional, LED lighting is a complete electronic products, and the traditional lighting is only an electrical product. Therefore, LED lamps can be easily associated with various types of sensors, enabling light control, infrared control and other automatic control functions. Such as LED lights automatically switch, with a photosensitive sensor can be simply achieved; community night walkway and courtyard lighting, infrared sensors can be used to collect information on human activity, automatic lighting switches off.
Photosensitive sensors and LED lighting portfolio
Scenery LED street light is a highly intelligent and unattended road lighting, the use of wind, solar power generation, battery storage, so the automatic energy management is very important. Photosensitive sensor is ideal because of dawn, dark days (sunrise, sunset) when the illumination changes can control the circuit automatically switches electronic sensors.
Photosensitive sensors can be based on the weather, time zones and regions automatically control the mall LED lighting on and off. Reducing power consumption by reducing its output during bright daylight saves up to 53% less power in convenience stores with a store area of ??200m2 compared to when using fluorescent lights. Life expectancy up to about 5 to 10 million hours. Under normal circumstances, the life of LED lighting is about 40,000 hours; glowing colors can also be RGB (red, green and blue) colorful way to make the mall more colorful lights, the atmosphere more active; and supporting the use of yellow phosphor Compared with the original blue LED, the purple LED supporting the use of red, green and blue phosphors has higher color rendering.
Infrared sensors and LED lighting portfolio
Infrared sensors rely on the human body to detect infrared emission and work. The main principle is: the human body about 10 发 infrared emission through the Fresnel filter lens enhanced to pyroelectric components PIR (passive infrared) detector, when people move, the emission position of infrared radiation will change , The element loses the charge balance and releases the charge due to the pyroelectric effect. The infrared sensor converts the change in the infrared radiation energy transmitted through the Fresnel filter lens into an electrical signal, that is, thermoelectric conversion. When there is no human body moving in the detection area of ??the passive infrared detector, the infrared sensor senses only the background temperature. When the human body enters the detection area and the Fresnel lens, the pyroelectric infrared sensor senses the human body temperature and Background temperature differences, the signal is collected after the system has been detected with the data to compare to determine whether someone really infrared source into the detection area.
Passive infrared sensors have three key components: Fresnel filters, pyroelectric infrared sensors and matched low-noise amplifiers. Fresnel lens has two roles: First, the focus effect, the infrared signal is about to refract the pyroelectric infrared PIR: Second, the detection area is divided into a number of bright and dark areas, so that the detection area of ??moving objects / person can Generates a changing pyro-infrared signal on the PIR in the form of a temperature change. In general, the noise amplifier is also matched. When the ambient temperature on the detector rises, especially when it is close to normal human body temperature (37 ° C), the sensitivity of the sensor drops and the gain is compensated for thereby increasing its sensitivity. The output signal can be used to drive electronic switches to control the switching of LED lighting circuits.
In recent years, ultrasonic sensors that are similar to those of infrared sensors have been used more and more in automatic detection of moving objects. Ultrasonic sensors mainly use the principle of Doppler, outward emission through the crystal beyond the human body can be perceived high-frequency ultrasound, the typical choice of 25 ~ 40kHz wave, and then the control module detects the frequency of reflected waves back, if there is movement within the region, reflection Wave frequency there will be slight fluctuations, that is, Doppler effect, in order to determine the illumination area of ??the object movement, so as to achieve the purpose of control switch.
The longitudinal oscillation of ultrasonic waves can propagate in gas, liquid and solid, and its propagation speed is different. It also has refraction and reflection phenomena. It has low frequency of propagation in air, rapid decay, and attenuation in solid and liquid Small, spread far. Ultrasound sensors make use of these characteristics of ultrasound. With its sensitive range, no blind spot and no interference with obstacles, the ultrasonic sensor has been used in commercial and security fields for more than 25 years and has been proved to be the most effective way to detect the movement of small objects. Therefore, with the LED lighting system can be sensitive control switch.
Due to the high sensitivity of the ultrasonic sensor, air vibration, ventilation, heating and cooling system and the surrounding space around the movement will cause ultrasonic sensor false trigger, so the ultrasonic sensor needs to be calibrated in time.
Temperature sensor LED lighting over-temperature protection
Temperature sensor NTC (negative temperature coefficient) to do LED lamps overheating protection is widely used earlier. LED lamps, such as the use of high-power LED light source, you must use a multi-wing aluminum radiator, LED lighting for interior lighting itself is very small space, the heat problem is still one of the largest technical bottlenecks. LED lamps heat unhappy words, will lead to LED light source due to overheating and early light failure. After the LED lamp is turned on, the heat will also be enriched to the lamp cap due to the hot air automatically rising, affecting the life of the power supply. Therefore, in the design of LED lamps, aluminum radiator near the LED light source side close to a NTC, in order to collect the temperature of the lamp in real time, when the lamp cup aluminum radiator temperature can be used to automatically reduce the output current of the constant current source, So that the lamp cooling; when the lamp cup aluminum heatsink temperature limit to automatically switch off the LED power supply settings, the lamp over-temperature protection, when the temperature decreases, the lamp will automatically turn on.
Conclusion:
Because of the LED lighting is a complete electronic products, with the diversification of LED lighting structure, the application of magnification, with more innovative LED lighting design, innovation, there will be more sensors are used in conjunction with the LED lighting and Lighting engineering system to go. A new era of intelligent LED lighting is coming, the lighting of human life will be more brilliance and comfort.
