I am going to use a magnetic mechanical relay to switch 240v AC.
I am using MPC250D6Z05APT, in its specification it did not say that the 5V signal is isolated from its output upon failure of the product.
My question is by nature of mechanical relays are the signal pins/ coil pins isolated from its output terminal?
If not, how would you create a protection circuit, without having external power supplies?
Here is what I though up with using traditional opto isolator, but I am not confident since the 5V supply is still coming from the same board.