Make a Relay Modul With Optocoupler

Introductions :
Relays are mechanical switches ,compare to semi-conductor there switching time are very slow , but it switch in relatively high voltage,One example use of relays are in the Car or bike as electric ignition they increase relatively low current from the battery to high thereby igniting the engine.

Descriptions :
we will be making a relay modul to be use with an optocoupler , the optocoupler is the main component of our circuit it separate between the micro controller and the the circuit with higher voltage (using light ) .”

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