Introduction to Reed Switch Sensor

A magnetic contact switch is essentially a reed switch encased during a plastic shell in order that you’ll easily apply them during a door, a window or a drawer to detect if the door is open or closed. The switch that we are getting to use has two parts: the switch itself, that sometimes comes opened and therefore the magnet. once you buy this switch, it also comes with 4 screws, in order that you’ll attach it to your door.

Types Of Reed Switch

There are two fundamental types,

Normally Open Type

In a normally open switch, the two reeds, which are made from ferrous material such as a nickel-iron alloy are positioned so that they are not touching. When a magnet is moved close to the switch, it pulls one of the reeds towards the other so that they are touching, and therefore completing the circuit.

Normally Closed Type

A normally closed switch works in the opposite way, when no magnetic field is present the reeds are in full contact, the electric circuit is complete and the device is ‘on’. When a magnet is moved close to a switch, or the switch close to a magnet, the reeds repel one another and split apart, breaking the circuit. 

Advantage Of Reed Switch.

01. No mechanical wear: because there is no physical pressure applied to the switch, there is no mechanical wear and tear.

02. Operated through a non-magnetic material: sensors can be developed with such sensitivity that they can be embedded deep within an assembly out of sight but still actuated by a reasonably strong but discreet magnet.

03. No supply of voltage: as they are triggered by magnetism, there is no voltage required.

04. Compact: reed switches are incredibly compact compared to mechanical switches.