The 10pcs Sensitive SW520D SW520 Ball Switch Vibration set provides a compact and reliable vibration sensing solution for electronics projects and consumer devices. Built around a ballincapsule switch, it closes its two terminals when subjected to movement or vibration, delivering a simple digital signal to microcontrollers, alarms, or other logic circuits. Key benefits Simple, lowcost motion sensing: a passive ball switch that generates a contact closure on vibration without complex electronics. sensitivity: designed to detect even small movements, making it suitable for knocks, taps, and movement detection. Easy integration: twoterminal device that can be connected to common microcontroller inputs with pullup or pulldown resistors. Compact and versatile: tiny form factor ideal for PCB mounting in compact devices and DIY projects. Economical multipack: includes 10 pieces, providing spare sensors for multiple projects or testing. Key attributes Model: SW520D, also referenced as SW520 Ball Switch Vibration Type: twoterminal vibration sensor switch (ballincapsule) Operation: closes its contacts momentarily in response to vibration or movement Terminals: two leads for straightforward electrical connection Housing: compact, sealed switch suitable for integration into electronics projects Sensitivity: marketed as sensitive to vibration Package: 10 units per Applications and use cases Vibration and motion sensing in consumer electronics: detect knocks or device movement to trigger a response in the firmware. Security and antitheft systems: use as a movement sensor in doors, safes, or alarm panels to trigger alerts when tampered with or moved. Interactive projects and robotics: enable shake or impact detection for games, wearables, or small robots, providing a simple trigger input for control logic. How to use Connect one terminal to a microcontroller input with a suitable pullup or pulldown resistor, and connect the other terminal to the opposite reference. When vibration occurs, the switch will close, producing a digital transition that can be read by the control logic. Mount the sensor securely within your enclosure to ensure reliable movement transmission to the internal mechanism. Notes This is a mechanical contact switch; no active power is required to sense vibration, but proper wiring and debouncing in firmware may be beneficial for clean readings. Suitable for lowcurrent switching typical of digital input signals; verify compatibility with your circuit design and input thresholds. The 10piece pack offers a convenient supply of sensitive SW520D vibration sensors for development, testing, and production prototyping, enabling reliable motion detection across a range of devices and applications.