The converter should be mounted as close as possible to the battery bank. The closer the better, but not in the same compartment. Also, the wire size matters, both between the panels and the controller and the controller and the batteries.
2014 RAM 2500 Laramie 4x4 Quad Cab w/Cummins Turbo Diesel, 2009 Rockwood 2607, and 3 'yaks!
300W of Suntech Solar, a Rogue MPT-3024 Controller, and a Xantrex PW2000 Inverter