Can Trailer Battery Be Charged Through Trailer Wiring Connector

Question:

Hello, I have been reading a lot of questions about using a 7 pin from the vehicle to charge a 12V deep cycle battery on a trailer. Some of the answers differentiate between maintaining charge and charging the battery. I fear that this is a stupid question, but I dont understand the difference. Im building a tear camper that doesnt require much amperage to run the interior lights, but I hope that when the trailer is hooked up to the tow vehicle and various tow vehicles the battery can be topped off through the 7 pin connector. Is this possible?

asked by: Nate S

Expert Reply:

The gauge wire used for the 12 volt pin of a 7-way is light enough that you'd never be able to charge a dead battery on a trailer with it, but if you were in a situation where you had a battery with a solid charge on it that needed to be kept topped off while traveling charging it through the 7-way will work just fine for that.

Basically the amperage is so low that it can't really put a heavy enough charge on it to bring a dead battery back to life, but after some light use on a charged battery the battery will be kept topped off.

You'd want to use 10 gauge wire like part # 10-1-1 (sold by the foot) from the connector to the trailer battery's positive post.

expert reply by: Jameson C