Ruh-roh!

I'm trying to figure out how to reset a circuit breaker which doesn't look like a circuit breaker.

Here's a picture of what is supposed to be a breaker panel:

AND

The wiring diagram for this neck of the woods:

These pictures are here for the benefit of folks on rv.net who are generous with their time, but if anyone has a clue about how to reset such a breaker. I'm all ears.

Thanks!