After finishing up the tail and brake lights I was able to pull the wire for the refrigerator inverter. Because I’m designing to be off-grid/dry camp, I need the refrigerator to run on the 12 volt system and not 120 volt grid power. A dedicated 750 watt inverter is now mounted under the ridge in the storage area. This allows lots of cooling air as well as keeps the large wires out of sight.
The inverter positive voltage comes from a 6 gauge stranded conductor tied directly to the deep-cell battery. While running the fridge only consumes about 140 watt, but the startup surge (from the inductive nature of the compressor) can be over 400 watts. The non-sinewave AC also contributes to a little efficiency loss. But, I cannot justify a true sine-wave inverter for a $150 fridge.
The inverter ground (negative) is bolted to the frame using the correct connector. It took quite a bit of sanding to get to the steel of the frame. A 1/4 bolt with nylon lock nut was then used to tie the connector to the frame. The battery negative has also been tied to the frame in the same manner. (Matching the brake battery configuration although the brake battery is not tied to the interior system at this time.)
Outside temperature was a little over 100 when I finished up. The inside of the house was hovering between 91 and 94 depending which thermometer you looked at. Within an hour the fridge was down into the 40’s.