The Reed Switch Module is a simple magnetic switch sensor that detects the presence of a magnet and provides a digital output signal. It contains a reed switch sealed inside a glass tube, which closes (or opens) when a magnetic field comes near. This module is widely used in door/window security systems, position detection, proximity sensing, and automation projects with Arduino and other microcontrollers.
Core Sensor Specifications
• Sensor Type: Magnetic reed switch sensor module
• Detection Method: Magnetic field detection
• Switch Type: Normally Open (NO) / Normally Closed (variant dependent)
• Output Type: Digital trigger output
Electrical & Interface
• Operating Voltage: 3.3 V – 5 V DC
• Output Pins: DO (digital output)
• Interface Pins: VCC, GND, DO
• Onboard Circuit: LM393 comparator (common variants)
• Sensitivity Adjustment: Onboard potentiometer (variant dependent)
Performance Characteristics
• Detects magnet presence reliably
• Fast response time
• Low power consumption
• Stable output for microcontroller input
Physical Characteristics
• Sensor Element: Glass reed switch tube
• Mounting Hole: Provided for installation
• Compact and lightweight PCB
• LED Indicators: Power LED + Output LED (variant dependent)
Compatibility
• Arduino Uno / Nano / Mega
• ESP8266 / ESP32
• Raspberry Pi GPIO
• Home security and automation systems
• DIY magnetic sensing projects
Key Advantages
• Simple magnetic ON/OFF detection
• Long life with no mechanical wear
• Easy integration with digital input pins
• Ideal for security and position sensing
Technical Insights
• Works only when magnet is close to reed switch
• Glass reed switch is fragile, handle carefully
• Output polarity may vary based on module design
• Avoid strong magnets for long duration near switch
Applications
• Door / window open-close detection
• Magnetic security alarm systems
• Limit sensing in robotics
• Drawer and cabinet monitoring
• Position and proximity sensing projects
Pro Tip
• Keep magnet aligned with reed switch for best detection
• Use pull-up/pull-down as needed for stable logic
• Mount securely to avoid false triggering due to vibration
• Test distance range before final installation
Package Includes
• 1 × Reed Switch Module