A reed switch, also known as a reed sensor or magnetic switch, is an electrical switch that is activated by the presence or absence of a magnetic field. It consists of two or more flexible metal reeds sealed within a glass or plastic tube filled with inert gas.
The reeds are made of ferromagnetic materials, such as nickel-iron alloys, that can be magnetized. When a magnetic field is applied to the switch, the reeds are attracted to each other, closing the electrical circuit. When the magnetic field is removed, the reeds spring back to their original position, opening the circuit.
Reed switches are simple, reliable, and have a long operational life. They are commonly used in various applications, including proximity sensing, position detection, and security systems. For example, they can be used in door and window sensors, liquid level sensors, flow meters, and burglar alarm systems.
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