How Relay works - tutorial

Dear Friends, There is an old saying that " With electricity Switches can do wonders" ... Switches can be found every where. We all are surrounded by these tiny little wonder. There are lots of different types of switches, in which RELAY is also one. Everytime manually going and switching on the circuit is not possible . which can be automated with the use of Relay. Relay is a simple switch if i say perfectly its an automatic switch which simply works with electromagnetic principle. Electromagnetic principle : when current passess through a conductor( Which lets the charges to flow from it- ex :copper wire,iron piece) a Magnetic field is generated around the conductor. Relay is divided into Four parts : 1.) Coil ( refer circuit - shape of spring) 2.) A metal plate ( refer the circuit- two parallel lines right next to coil). 3.) One input terminal 4.) Two ouput terminal As per electromagnetic principle The current flows from the coil(Refer circuit- shape of spring) a magnetic field is generated around the coil which makes the metal plate (refer circuit- two parallel lines next to coil) magnetised. Which will attract the inbuilt metal switch ; then the switch shifts itself from one terminal to another due to this attraction. So this means from one switch we can control & complete other circuits and also with just using a small current we can make large current to flow from one point to another. Press the switch situated at left side to operate the relay. When switch is closed current flows from left end battery to the relay coil which makes the metal plates magnetised which attracts the switch and completes one circuit. But when switch is open no current flows to the coil which makes the switch to remain in the open state and complete another circuit. ( stimulate circuit with the switch to understand easily). Regards, Happy learning.

published 10 years ago