Reed Sensor Magnetic Switch Module

The Reed Sensor Magnetic Switch Module is an electromagnetic device designed to detect the presence of a magnetic field. Built around a sealed glass reed switch, it closes its contacts when a magnet is brought near, making it perfect for proximity sensing, security alarms, and speed detection. With its reliable operation, simple digital interface, and fast response time, it is widely used in security systems, robotics, and DIY electronic projects.

Key Features

• Highly sensitive to magnetic fields
• Digital output for easy microcontroller interfacing
• Sealed reed switch for protection against dust and moisture
• Fast response time and long operational life
• Wide operating voltage compatibility (3.3V to 5V)
• Low power consumption
• Often includes an LM393 comparator for clean digital signals

Technical Specifications

Applications

• Door and window security alarms
• Magnetic proximity sensing
• Speed and RPM measurement (with magnets on rotating discs)
• Water level sensing
• Robotics and automation limit switches
• DIY electronics and IoT projects

Important Notes

• Keep the reed switch away from strong external magnetic fields during storage to prevent unintended activation.
• Avoid dropping or applying strong physical shock to the module, as the glass reed switch inside is fragile.
• Ensure the power supply voltage does not exceed 5V to prevent damage to the onboard comparator and components.
• Use a suitable resistor if driving LEDs or relays directly from the output pin to avoid exceeding current limits.
• Verify the polarity of the VCC and GND pins before powering the module.