MicroWave Radar Motion Sensor(RCWL-0516)

Introduction

The RCWL-0516 is a low-cost, radar-based motion sensor module widely used in DIY electronics projects and security systems for detecting human movement. Unlike passive infrared (PIR) sensors, which detect changes in infrared radiation, the RCWL-0516 uses Doppler radar technology to sense motion. This allows it to detect motion through certain materials (like glass and thin walls), making it more versatile in terms of placement.

Key Features

1. Microwave Doppler Radar Technology: The RCWL-0516 emits microwave signals at 3.2 GHz and detects motion based on changes in these waves, offering high sensitivity to movement.
2. High Detection Range: Typically, the sensor detects motion up to a range of 5-7 meters.
3. Wide Detection Angle: It has a detection angle of around 360 degrees, which means it can detect movement from any direction, depending on its surroundings.
4. Sensitivity to Non-line-of-Sight Motion: Since it’s based on microwave radar, it can detect motion through materials like wood, glass, and even thin walls, which is advantageous for concealed installations.
5. Operating Voltage: It works on a 4-28V DC supply, with a low power consumption rate of 3mA.
6. Signal Output: When motion is detected, the output pin goes high, making it easy to integrate with microcontrollers (like Arduino, Raspberry Pi, etc.).

How It Works

The RCWL-0516 sensor sends out electromagnetic waves and waits for them to bounce back from nearby objects. When someone moves within its detection range, the reflected waves change, causing the sensor to trigger its output pin.

1. RCWL-0516 module
2. 5V relay module
3. jumper wires
4. 5-9v power supply

1---->3.3 v out(regulated 3.3v output with 100mA)

2--->Ground

3--->Signal output(High pulse)

4--->Voltage in (4-28V)

5---->CDS pin(We can add the LDR externally to the module rather than placing on the CDS pad. Connect one leg of the LDR to this pin and another leg to ground)

1---->R-CDS

2--->R-GN

3--->C-TM

C-TM (Pulse length Adjustment): we can extend the output pulse length based on the capacitor on the C-TM pad. The default duration is 2 seconds. Higher the capacitor value ,the longer the pulse duration.

R-GN (Detection Range Adjustment): we can reduce the sensor’s detection range based on the resistor on R-GN pad. By default, the detection range is set to 7m.Higher the resistor value higher the detection range(max is 7m).

R-CDS (Light Sensitivity Adjustment): use this as an alternative to soldering the LDR on module.

Connect vin to dc+

gnd to dc-

out to IN

connect COM and NO of relay module to ac line or other switching circuit

NOTE: Here i used an old 9v battery were the voltage is dropped. Don't use a new 9v battery to this circuit, as it may destroy the relay module. Use a regulated 5v supply.

Never use the RCWL_0516 module with a breadboard , The metal connection pads inside the breadboard will cause interference and reduce the detection range to few centimeters

ENJOY_BUILDING_THE _PROJECT!!!