Please help - electrical question / problem

[unkeljason]

Can anyone tell me what this part is called ? Obviously it is rusted out and corroded. The red wire from my switchboard ( for lights / aerator and bilge ) was attached to one end, and the red wire coming out of my battery switch was attached to the other - I removed those wires from this because it is in such bad shape / I also was troubleshooting why I am getting NO power to my switchboard and this seemed to be the first sign that I saw. Any advice would be really helpful - Thank you

 

[bilge rat jim]

That's a DC circuit breaker, and it looks like it's had it. You can test it with an ohmmeter- you should have continuity from one terminal to the other. If you have to replace it, the amperage should be stamped on the casing. It looks like all your connections need to be taken apart and cleaned.