8 pin magnetic relay generally known as 2 C/O relay because in this relay generally 2 common point 2 NC points and 2 NO points presents so we can control two device are equipment generally control at a time.
In this video we explain how relay works and types of relay and 8 pin relay working.
And also in practical we control and on two bulb at a time and in next practical we in one time one bulb and off another bulb with help of 8 pin relay .
For more understanding just watch and learn
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