This straightforward but incredibly intelligent smart LED street light circuit turns a street lighting on automatically when it senses movement beneath it, turning it from low to high brightness.
Only at night does this operation begin; during the day, the street lamp is turned off entirely.
What this Circuit will do
Essentially, this sophisticated autonomous street lamp circuit will carry out the following tasks:
During the day, keep the streetlamp fully off.
Turn on the street lamp automatically at night or in the evening at a 50% decreased brightness.
Instantly reach maximum brightness if the lamp detects a moving item beneath it.
Turn the brightness back to 50% as soon as the moving item has passed.
In order to prevent abrupt transitions between high and low brightness, a two-second delay is added.
Main Advantages
The primary benefits of this smart street lamp circuit are significant power savings and a significant improvement in the street lamp system's operational efficiency.
Because street lighting is automatically turned off throughout the day, electricity is conserved.
When a street lamp is 50% bright and there isn't a moving car or person below it, electricity is conserved.
By using LEDs, lights become even more energy-efficient and efficient overall.
This totally automated street light saves labor and salary by doing away with the need for human intervention.
The LEDs' lifespan is increased significantly by the automated daylight shut-off and the lower brightness in the idle mode, which lessen stress and wear on the lights.
Circuit Description
As can be seen in the figure below, the RCWL-0516 microwave radar motion sensor module is used in the suggested smart streetlamp circuit.
See the accompanying image for the full circuit diagram of this smart streetlamp project:
The following details will help you understand how the circuit above operates:
Doppler radar is a technique used by the microwave radar sensor RCWL-0516 to identify moving objects.
In our smart street light circuit, we employ this RCWL-0516 sensor module to identify moving objects beneath it and initiate a 50% to 100% brightness level change.
When an object moves within three meters of the lamp post—a human, an animal, or a car—the RCWL-0516 senses it immediately away and toggles to full brightness.
A couple of LED bulbs, one rated at 40 watts and the other at 20 watts, are shown in the diagram.
Using the N/C contacts of the relay, the 20-watt bulb is kept lit at night when no one is walking by beneath the street lamp.
When a moving target is identified, the RCWL-0516 activates the relay, causing its contacts to transition from N/C to N/O, turning on the 40 watt bulb and turning out the 20 watt bulb.
As a consequence, the brightness increases from 50% to 100%, giving the target that is moving the best possible visibility on the road.
The RCWL-0516 resets the relay to its initial N/C state so that the 20 watt bulb is subsequently turned ON and the 40 watt lamp is switched off when the target has moved farther away from the lamp .
Daytime Automatic Switch OFF
A built-in function of the RCWL-0516 module enables it to work with an LDR to detect ambient light and be inactive throughout the day.
In other words, irrespective of whether a shifting target is present or not, the entire street lighting stays disabled while a respectable quantity of ambient light is accessible.
The street lamp becomes completely operational when the RCWL-0516 is triggered, which happens as soon as the darkness level falls below the predetermined threshold.
As seen in the accompanying diagram, the RCWL-0516 module's LDR connection information is located on the other side of the module:
Parts List
| Component | Specification |
|---|---|
| Resistor (4.7 kΩ) | 4.7 kΩ, 1/4 watt, 5% CFR (1 piece) |
| Transistor (BC547) | BC547 (1 piece) |
| LED (3.3 V, 5 mA) | 3.3 V, 5 mA LED (1 piece) |
| Diode (1N4007) | 1N4007 (1 piece) |
| Relay (12V, 5-pin) | 12V, 5-pin Relay (1 piece) |
| Module (RCWL-0516) | RCWL-0516 Microwave Radar Sensor Module (1 piece) |
| Power Supply (12V SMPS) | 12V, SMPS Power Supply (1 piece) |
| LDR (Light Dependent Resistor) | LDR (1 piece) |
This brings an end to our discussion of smart LED street lamps with motion detectors, which are quite effective at saving both labor and electricity.
Please use the provided comment box below to ask any other questions you may have about the aforementioned project.