1. Overview

Magnetic reed switches are electromechanical switching devices operated by an applied magnetic field. Comprising ferromagnetic contacts sealed in a glass envelope, they enable contact closure (or opening) without physical actuation. Their hermetically sealed design ensures reliability in harsh environments, making them critical components in modern automation, security systems, and industrial equipment.

2. Main Types & Functional Classification

3. Structure & Composition

Typical structure includes:

• Hermetically sealed borosilicate glass capsule
• Electroplated ferromagnetic nickel-iron contacts (0.1-0.2mm thickness)
• Inert gas atmosphere (usually nitrogen or argon)
• External magnetic actuation source (permanent magnet or electromagnet)

Advanced variants feature sputtered ruthenium/tungsten coatings for improved contact durability.

4. Key Technical Parameters

5. Application Fields

• Consumer Electronics: Smart home sensors, wearable devices
• Automotive: Transmission position sensors, anti-theft systems
• Industrial: Flow meters, valve position monitoring
• Medical: MRI machine interlocks, infusion pump controls
• Security Systems: Window/door intrusion detection

6. Leading Manufacturers & Products

7. Selection Guidelines

Key considerations:

• Contact configuration (NO/NC/CO) matching control circuit requirements
• Environmental factors: Temperature (-40 C to +150 C typical), vibration resistance
• Electrical parameters: Must exceed 20% of application requirements
• Actuation method: Fixed magnet position vs. movable magnet systems
• Mounting orientation: Axial vs. radial mounting constraints

Case Study: Smart meter applications require reed switches with >10⁸ operations life and anti-tamper certification.

Industry Trends

Emerging developments include:

• Micro-scale reed switches for IoT devices (under 3mm size)
• Integrated Hall effect sensor combinations
• Graphene-coated contacts for ultra-low resistance (0.01 typical)
• Wireless reed switch modules with BLE connectivity
• Increased adoption in renewable energy systems for contactor control