1, Technical principle: Multimodal perception and precise control
The collaborative work of LED linear lights and human body sensors relies on the precise capture of environmental signals by sensors and the fast response of lighting fixtures. The current mainstream induction technologies include infrared pyroelectric (PIR) and millimeter wave radar, each with its own emphasis on principles and applicable scenarios.
Infrared Pyroelectric (PIR) Technology
The PIR sensor focuses the 10 μ m wavelength infrared radiation emitted by the human body through a Fresnel lens. When the human body moves and the distribution of thermal radiation changes, the sensor outputs an electrical signal to trigger the lighting fixture. Its advantages lie in low cost and low power consumption, but there are two major limitations: first, it requires human movement to trigger and is not sensitive to stationary targets (such as seated readers); Secondly, it is susceptible to environmental temperature interference, and its sensitivity decreases when it approaches human body temperature (37 ℃). For example, a certain brand of PIR induction linear lamp needs a human movement speed of over 0.5m/s to trigger in an environment of 30 ℃.
Millimeter wave radar technology
Radar sensors detect human body micro movements (such as breathing and heartbeat) using the Doppler effect by emitting 24GHz or 60GHz electromagnetic waves, and can continuously perceive even when the target is stationary. It has strong penetrability, can penetrate non-metallic materials such as thin wooden boards and plastics, and has excellent anti-interference ability. Taking the Lingpu ES2 sensor as an example, it uses a 60GHz radar chip that can accurately identify the presence of a human body within a range of 8 meters, with a misjudgment rate of less than 0.1%. It also supports IPX7 waterproof and is suitable for humid environments such as bathrooms.
Dual mode fusion technology
To compensate for the shortcomings of a single sensor, some high-end products adopt a PIR+radar dual-mode design. For example, the fence power ARGUS sensor combines passive infrared and ultrasonic detection to activate radar fine sensing when detecting large-scale motion, achieving a synergistic effect of "coarse detection+fine positioning", suitable for complex scenes such as large shopping malls and parking lots.
2, Application scenario: Full coverage from home to business
The combination of LED linear lights and human body sensors can flexibly adjust the control logic according to spatial functional requirements, achieving a balance between lighting efficiency and user experience.
Home scene: equal emphasis on safety and energy conservation
Entrance/hallway: Install radar sensing linear lights and set a 5-second delay to turn off. When homeowners return home at night, the lights should be lit up step by step to avoid walking in the dark; After leaving, it will automatically turn off to prevent the phenomenon of long on lights.
Wardrobe/cabinet: embed PIR sensing light strips inside the cabinet, which will light up instantly when the door is opened, illuminating the internal items; Turn off within 0.5 seconds after closing the door to reduce the interference of light overflow on sleep.
Staircase: Radar sensing step lights are used, which trigger local lighting by detecting step pressure, saving energy and avoiding visual stimulation caused by overall lighting.
Business scenario: Experience and efficiency improvement
Clothing store fitting room: Install radar sensing linear lights that automatically adjust to 3000K warm light when customers enter, creating a warm atmosphere; After leaving, switch to 5000K neutral light for easy cleaning and maintenance.
Supermarket shelves: Install PIR induction light strips on the top of the refrigerated cabinet, increasing the brightness to 800lm when customers approach, highlighting product details; Reduce energy consumption by 30% to 200lm when unmanned.
Office corridor: using radar sensors and linear lights to dynamically adjust brightness according to personnel density. For example, maintaining a brightness of 30% for single person travel and increasing it to 70% for multi person travel, achieving "on-demand lighting".
3, Installation and Debugging: From Standardized Operations to Intelligent Optimization
Proper installation and debugging are key to ensuring stable system operation. Taking a certain brand of radar induction linear light as an example, summarize the key steps:
preliminary preparation
Tools and materials: 1.5mm ² copper core wire, insulation tape, measuring pen, wire stripping pliers, screwdriver, leakage protector.
Location selection: The sensor should be installed at a height of 2.2-2.5 meters, avoiding heat sources such as air conditioning and heating, as well as areas with direct sunlight; Linear lights should maintain a distance of 10cm from the wall to avoid shading.
Wiring process
Power off operation: Turn off the main power and use a measuring pen to confirm that the circuit is powered off.
Line connection: Connect the live wire to the L end of the induction switch, connect the neutral wire to the N end, and connect the grounding wire to the PE end; Connect the control line to the OUT terminal and the linear lamp drive power supply.
Parameter settings: Adjust the photosensitive sensitivity (recommended 10-20Lux), delay time (3-5 minutes), and sensing range (3-5 meters) through the mobile app or switch panel.
Testing and Maintenance
Functional testing: Simulate human movement to check the response speed and accuracy of delayed closing of lighting fixtures; Use an infrared thermal imaging device to detect the presence of light leakage areas.
Regular maintenance: Clean the surface dust of the sensor every six months and test the function of the leakage protector; Replace the capacitor components every two years to extend the system's lifespan.
