I'm a little fuzzy on my electrical knowledge here and I was hoping for someone to shine a little light on the subject. I've bought a couple of these 50 amp surface mount breakers from WAYTEK. I'm going to be using them on a 12V system. One of them (the automatic reset one) is rated for 30V DC. The other (the manual reset w/ trip push button) is rated for 48V DC.

Does this mean that on a 12V system, they won't trip unless they are drawing much more than 50 amps? If so, how much more?

Also, they have an interrupt rating of 3000 amps. What does this mean?

Thanks.