How should I protect my computer for overvoltage??

I was traveling by this forum and I see a topic about a fried MAC because a abd wiring and someone said the fuse on the arduino works for overcurrent but not overvoltage.
I have some projects in mind, some of them involve high voltage (30 DC and 110AC) to turrn on lights and stuff.

I dont use nothing to protect my computer, I obviously have relays, this are good protection or I should try something like optocouplers

Thanks

With relays and you still managed to fry a computer?!
Use optocouplers and learn how to use then.

I dont use nothing to protect my computer, I obviously have relays, this are good protection or I should try something like optocouplers

Relays give very good voltage isolation, however damage from dumb wiring errors is very hard to prevent.

Lefty

I dont fry my computer. I said that my project include several relays, and thats all the protection I have. I was asking if the relays are really a “protection”.

The fried computer was the same someone talk about in the forum

Thanks anyway. I will start to use the Opt… at least to consider them in my next project.