A good thread on Starcool is here:https://www.sportsmobileforum.com/fo...nfo-26005.html
I included a relay flowchart that was in that link. The small circuit breaker you are talking about feeds the fuse block and relay panel discussed in this thread. I would check to make sure the fuse panel is OK. The circuit breaker is supposed to be 40 amps, it doesn't appear the that individual fuses are blowing so, I would look at the circuit breaker first.
The other circuit breaker goes to your house distribution fuse panel. I believe it is also 40 amps.
If it isn't the breaker, you can follow the flowchart, and turn things on as individually as you can. That might lead you to what items might be drawing more current then expected.