Wiring a charge line to battery on utility trailer

~DJ~ wrote:
Hello. I've mounted a winch and battery on the front of my utility trailer. I would like to keep the battery topped off while driving down the road. The trailer is currently equipped with a flat 4 connector. No trailer brakes. Can I replace it with a 7 pin and just run the charge line to positive side of battery and ground pin to negative side? Or do I need some type of junction box? Thanks for your help. DJ