12mm Reed Switch / Magnetic Sensor

The 12mm Reed Switch / Magnetic Sensor is a compact magnetic proximity sensor designed to detect the presence or absence of a magnetic field. It consists of a hermetically sealed glass tube containing two ferromagnetic reed contacts that open or close when exposed to a nearby permanent magnet. This simple, reliable, and contactless sensing mechanism makes the reed switch ideal for position detection, security systems, industrial automation, and embedded electronics applications.

The sensor operates without requiring continuous power for detection. When a magnet is brought close to the reed switch, the internal reed contacts attract each other and either close or open the electrical circuit (depending on the switch type). Once the magnet is removed, the contacts return to their original state. The sealed glass construction protects the contacts from dust, moisture, and corrosion, ensuring long-term reliability and stable operation.

With a 12mm cylindrical body, the reed switch is easy to mount in panels, doors, enclosures, and equipment where compact magnetic sensing is required. It supports low-voltage and low-current switching applications and can be directly interfaced with microcontrollers, alarm systems, and automation circuits.

The 12mm Reed Switch / Magnetic Sensor is compatible with Arduino, ESP32, ESP8266, Raspberry Pi, STM32, PIC, AVR, 8051, NodeMCU, PLCs, and other embedded control systems. It is widely used in door and window security systems, position sensing, limit switches, level detection, industrial automation, robotics, home automation, educational STEM projects, laboratory experiments, and DIY electronics.

Features

• 12mm cylindrical magnetic reed switch

• Contactless magnetic field detection

• Hermetically sealed glass contact assembly

• Fast switching response

• Low power operation

• Reliable and long operational life

• Resistant to dust, moisture, and corrosion

• Compact and lightweight design

• Easy installation and mounting

• Suitable for low-voltage switching applications

• Stable and maintenance-free operation

Applications

• Door and window security systems

• Magnetic proximity detection

• Position sensing

• Limit switches

• Industrial automation

• Home automation

• Robotics and automation

• Liquid level sensing (with float magnets)

• Arduino and ESP32 projects

• Raspberry Pi embedded systems

• Alarm and access control systems

• Educational STEM projects

• Laboratory experiments

• DIY electronics and prototype development

Package Includes

• 1 × 12mm Reed Switch / Magnetic Sensor