Automotive Relays Explained

[@psilocin6739]

Thanks for the great explanation and demonstration. I'm a curious person and love how quick and efficient this video was. One thing i stiil am not sure on is: as long as the switch can handle it, why would you want or need to separate the larger current from the switch? I wired in a relay a little while ago for some fog lights but didn't really understand why i needed it.

[@busabobsgarage9876]

Happy to help. For the fog lights, the relay provides isolation, let's say in case of a short circuit. As you say, you could wire it with a beefy switch, fuse, wires, etc, bit think if you did that for each accessory on a vehicle. You would have a massive amount of heavy wiring, etc. You can see this if you open the fuse/relay panel on your car, what a relay would typically be used for.