Reed Switch-Reed Sensor

Reed switches also called as Reed Sensor is a electrical switch/sensor than can be operated by applying magnetic field.

The magnetic field causes closure of the reed contacts. Upon removal of the magnetic field, contact open again due to the elasticity of the reeds.

A reed switch consists of two ferromagnetic nickel-iron wires and specially shaped contact blades (reeds) positioned in a hermetically sealed glass capsule with a gap between them and in a protective atmosphere. The glass capsule is filled with inert gas to prevent activation of the contacts. The ruthenium or rhodium plated contact surfaces are isolated from the outside environment, which protects the contacts from contamination.

This is a small 14 mm Reed Sensor.

Features of Reed Switch

• compact size,
• low weight,
• quick response time,
• long life,
• Low cost. 

Applications of Reed Switch

• reed relays,
• automotive sensors,
• security systems,
• robotics,
• toys and games.