I am not an expert, Kate and I have never had to express this idea before. That's the only reason I thought I was wrong .What makes you think there's something wrong? We do talk about electric current passing through circuits and so on. It sounds perfectly fine to me.
It might do. It usually detects the faults that occur and interrupts the current flow .I honestly don't know much about electrical circuitry, so I can't tell you if electricity passes through circuit breakers or does something else there. But "electric current passes through ______" is definitely idiomatic.