Insight - How Reed Switch works
Magnets have a natural tendency to attract many things. Though not perceived as a real force, but it does attract human attention when a force acting invisibly draws things to itself. By harnessing this power, humans have made wonderful inventions like the electromagnet and discover lossless conduction phenomenon like superconductivity. Among these many inventions, was the application of magnetism to switch from ON state to OFF and vice-versa in precision devices. One such switching device, which works not by the principles of electricity, but magnetism, is the Reed Switch. 
Reed switches work like an electromechanical relay switch, while the latter conducts current, the former conducts magnetic flux which is the quantitative measurement of magnetic field on a surface. First Invented by Bell Laboratories, reed switches today have a length of just a few millimeters and are used in numerous applications that range from a simple coffee maker to rain gauge, and satellite TV positioning. Let’s have a look on how this unsophisticated looking device makes a difference.
Comments (2)
Hi..i dont know how to
Hi..i dont know how to interface reed switch, motion sensor and smoke sensor into an at89s52 microcontroller..can you help
me?
Below is the circuit to
Below is the circuit to interface reed switch with the MCU