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by BugWatch 1495 days ago
If you are ever to pursue such a project, please pay close attention to proper electronic circuit design and safeguards when it comes to relays. Otherwise, you risk burning out the controlling pins or the whole system, due to reverse voltage (measured in hundreds) that is generated by the relay's coil when the relay is turned off.

The easiest approach is to just use a commonly available relay modules used with Arduino or similar platforms/microcontrollers, as they already contain minimum or all protection mechanisms. So, the module will contain the reversed diode in parallel with the relay, while additional transistor and optocoupler will allow you a complete galvanic isolation of the controlling- from the and relay circuit.

YouTube has plenty of user-friendly resources with schematics and functional overviews, just search for "relay module" or "relay arduino".

1 comments

Oh, absolutely. Even though it's just a simple (mostly) isolated relay, driving outlet power through anything but a PSU sketches me out.

Great overview though, thank you for posting that.