Need Help - Battery Connection

[Dieselsite]

A friend bought a Keystone Bobcat trailer. I'm helping them get it ready for camping. The positive wire from the battery connects to the front of the trailer onto some form of relay/ contactor. Basically, its broken. Im not sure what it is, hence the reason for this post. I'm guessing the large red wire going into the trailer is the positive feed to the panel, and the small black wire is the charger wire, but why is there this cheasy connector? If I can't just use a junction panel to connect all thre wires together, where can I get this part?
Thanks for any help. Bob

[Johnnyfry]

Are you sure that the "relay" is not a circuit (overload) breaker?

If it has only 2 wire connections (1 in and 1out) it is a breaker. If it has more it improbably a relay.

John

[SteveC7010]

If there is a small black wire connected direct to the battery's + post, it might well be the hot wire out to the breakaway switch.

Can you post a pic of the thing you think might be a contactor? It is always easier to identify things from pics.

But taking a guess here, if the part you are referring to looks like this:

http://media.eglobalelectronics.com/media/catalog/product/cache/1/image/275x/9df78eab33525d08d6e5fb8d27136e95/A/ATSCB30.jpg

Then it is a circuit breaker and is necessary in the line. Replacements are readily available at auto parts stores for a lot less than you would pay at an RV parts counter.

[Dieselsite]

Thanks! That's what it looks like and I appreciate the help. Off to the auto parts store.
Bob