Magnetic Reed Switch Circuit

Wilkis october 17 1967.

Magnetic reed switch circuit.

A switch with one magnetic reed and one non magnetic one. 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. Sw1 opens whenever the magnet looses its contact with the reed switch. The contacts are usually normally open closing when a magnetic field is present or they may be.

When there is no magnetic field then ferrous materials separate and switch open. Quite a neat summary of how reed switches are used in. Describes various ways of making a normally closed switch. The contacts are concealed inside a glass tube and its ends terminated out of the glass tube for external connection.

There are normally open reed switches and normally closed reed switches. Normally closed reed switch by anthony j. They re perfect for any projects that require non contact control. 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.

It takes negligible power to pulse the coils of latching reed relays. The circuit then starts oscillating and the loudspeaker convey a loud alarm sound. However for an application such as a door security sensor the reed switch needs a protective shell housing for handling and mounting. The reed switch will remain in its closed state until another magnetic pulse with the opposite magnetic polarity is applied.

These packages offer resistance to mechanical stress by protecting the bare glass of the reed switch. 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. Simply put it is a magnetic switch.

How to build a reed switch circuit. 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. There are all sorts of creative applications for reed switches. By the way this element reacts as a non contact switch in a circuit and also it can carry upto 1 2a current.

Generally a 2 msec pulse supplied at the relay nominal voltage is enough to change the state of the relay contacts. This alarm circuit constructed by. 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. A bare reed switch can easily be mounted on circuit boards.

In its simplest and most common form it consists of a pair of ferromagnetic flexible metal contacts in a hermetically sealed glass envelope. Introduction to reed switches magnets and magnetic fields by stephen day.