Currently my TV is wired with only a 4flat harness, and I would like to be able to charge the trailer battery while towing. I am planning on putting in this adapter http://www.etrailer.com/Wiring/Hopkins/37185.html and running a 10awg line direct from the battery, with an isolator and 15A fuse inline. Will this be a heavy enough wire? What kind of current am I really expecting to be sending to that battery? Will I over draw the alternator on my '09 Acadia?