Relays

In: Science

Submitted By saadahmed
Words 769
Pages 4
What are relays?
Before, I talk about any particular relay – I think it is very important to clarify what exactly relays are?
As per my understanding, relay is basically a type of electromechanical switch It has electromagnet and several other components in it. Relays works on electromagnetic principles.
How relays work (theory)
A relay basically has two parts (circuits). One part (circuit) is the actual switch, which basically acts as a control of the current to electromagnetic and the relay itself is controlled by electromagnet. A relay is basically an incomplete circuit when it is turned off. It has arm which we call "armature" which completes the circuit if and only if the electromagnet is present (electromagnet is produced if we allow the current using the first circuit thus creating an electromagnetic..). So, if we turn on the first part of the circuit which allows the current to flow and consequently, electromagnet is produced in the circuit which produces a magnetic field around it - This electromagnet attracts the armature coil towards itself thus completing the circuit. Thus, the circuit is now completed and current flows through the entire circuit. Of course, if we want to simply stop the circuit at any time, we can simply switch off the first part of the circuit which means no current in the first part of the circuit and as such the electromagnet is no longer magnetic and thus the armature coil goes back to its initial position and circuit is now again open and the current is no longer flowing through the circuit. This is a very interesting concept. It’s very fascinating because this gives us a lot of flexibility as we can control large current using very small current. For electromagnet we don’t need very large current but consequently, when the whole circuit is closed and current flows through, we can actually allow a large current to…...

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