The RCWL-0516 motion detection sensor modules are compact microwave radar sensors designed for non-contact proximity sensing. Each module operates at a frequency of approximately 3.2 GHz and uses Doppler radar technology to detect moving objects, including humans and animals, within a range of 5 to 7 meters. The package includes 12 individually sealed modules, each with a small footprint measuring approximately 15mm x 11mm, making them suitable for space-constrained projects. The modules are built with standard pin headers for easy integration into breadboards or soldered connections.

These sensors are capable of detecting motion through non-metallic materials such as walls, glass, and plastic, offering reliable detection without the need for line-of-sight. The module outputs a high signal (3.3V logic level) when motion is detected and returns to low after a configurable delay. Sensitivity can be adjusted via an onboard trimmer potentiometer. The modules operate on a supply voltage range of 4 to 28 volts DC, making them compatible with common microcontroller platforms like Arduino, ESP8266, NodeMCU, Wemos, and Raspberry Pi.

The construction uses a rigid PCB with a clean solder mask finish and clearly labeled pins for power, ground, and output. The onboard antenna is integrated into the PCB trace, ensuring consistent performance. Each module undergoes basic functional testing before packaging, providing uniform sensitivity across the set. The modules are designed for low power consumption, drawing approximately 2.8 mA during active operation, which is beneficial for battery-powered applications.

In practical use, the modules can be employed for automated lighting, security alarms, presence detection in robotics, and interactive installations. The detection range is suitable for indoor environments such as rooms, hallways, or garages. The sensor's ability to work through obstacles reduces the need for exposed mounting positions. Users should note that the module does not provide speed or direction information, only presence or absence of moving objects.

The set of 12 units offers a cost-effective solution for projects requiring multiple detection zones or experimentation with sensor placement. The modules are RoHS compliant and sourced from a consistent production batch, ensuring similar electrical characteristics. With a price point that is very affordable, this bundle provides excellent value for hobbyists, educators, and makers looking to incorporate motion detection into their builds without significant expense.