Magnetic Reed Switch Circuit

The following magnetic reed switch alarm is made to be a home and handbag alarm that can be put on door on home windows or put it inside a bag a reed switch and a magnet form this circuit.

Magnetic reed switch circuit.

The contacts are usually normally open closing when a magnetic field is present or they may be. Sw1 opens whenever the magnet looses its contact with the reed switch. Wilkis october 17 1967. When a magnet is reached in proximity of s1 it closes to give a negative.

However for an application such as a door security sensor the reed switch needs a protective shell housing for handling and mounting. The contacts are concealed inside a glass tube and its ends terminated out of the glass tube for external connection. Introduction to reed switches magnets and magnetic fields by stephen day. Here is the circuit diagram of a magnetic proximity switch that finds a lot of applications in many fields the circuit is based on a magnetic reed switch s1 as the proximity sensor a monostable multivibrator based on ne555 ic1 and a toggle flip flop based on cd4013 ic2 does the rest of the circuit.

There are 2 basic types of reed switches. Generally a 2 msec pulse supplied at the relay nominal voltage is enough to change the state of the relay contacts. A magnetic door switch for example is just a dressed up reed switch and a mating magnet by keeping both parts of the switch separate the door can open and close freely and maintain its regular duties as a door the anemometer in our weather meter combines a. When there is no magnetic field then ferrous materials separate and switch open.

A reed switch is a very basic 2 lead switch that is switched on by a magnet being brought into the vicinity of the switch. It takes negligible power to pulse the coils of latching reed relays. Reed switch also called reed relay is a low current magnetic switch with a concealed pair of contacts that close and open in response to magnetic field near it. This alarm circuit constructed by.

How to build a reed switch circuit. A switch with one magnetic reed and one non magnetic one. There are normally open reed switches and normally closed reed switches. The reed switch is an electrical switch operated by an applied magnetic field it was invented at bell telephone laboratories in 1936 by walter b.

These packages offer resistance to mechanical stress by protecting the bare glass of the reed switch. There are all sorts of creative applications for reed switches. The circuit then starts oscillating and the loudspeaker convey a loud alarm sound. By the way this element reacts as a non contact switch in a circuit and also it can carry upto 1 2a current.

A bare reed switch can easily be mounted on circuit boards. Normally closed reed switch by anthony j. They re perfect for any projects that require non contact control. Describes various ways of making a normally closed switch.

The reed switch will remain in its closed state until another magnetic pulse with the opposite magnetic polarity is applied. When this device exposed to the magnetic field then ferrous materials inside reed switch pull together and switch closes.