In our coach the inverter is typically installed in the electrical compartment, which is the one that houses the 50A shore power cable. It sits directly opposite the battery compartment but is every bit of the 10′ limit to run up into the coach, over, and back down on the other side. In fact, the inverter needed to be mounted as close to the top of the cabinet as possible which meant building an angle-iron rack for it to sit on.
The rack is made of the same 1.5″ angle-iron as the battery rack. Normally you would weld the vertical support but since I don’t have a welder and was time constrained for access to one, I opted for the adhesive weld option. I found a YouTube video that put each of the metal bonding agents to the test. Being a long-time user of J.B. Weld I was surprised to see how early in the testing it failed. In the end Loctite Metal held out the longest and failed after 27lbs of 90 degree angular force was applied.
The inverter itself only weighs 25lbs and it won’t be direct angular force so this will do just fine. I bonded the angle-iron together before painting it so as to get the best possible adhesion. The pieces were clamped together to help ensure a tight bond. After using the Loctite Metal, I can say that it really felt strong and reliable. I used the same 3/8″ grade-8 bolts that used in the Battery Compartment Upgrade to bolt the cross members to the uprights. Once assembled and painted the pieces were placed inside the compartment and the uprights were screwed to the compartment walls using #14 self tapping stainless steel screws.
The wiring runs up through a pass-through in the battery compartment, into the space under the bed, and down through another pass-through into the shore power compartment. By far the hardest part of the entire install was fishing the wiring from the battery compartment into the coach. The pass-through runs under the rear slider and because of that there wasn’t a lot of room to maneuver. If you find yourself in a similar situation, use the trick us cable installers use and send a “pull string” through first. Tie the string to your wire and the string will guide it to the opening where you can grab it. You may still need to have someone inside push the wire toward you but the pull string will make your life easier. You will also want to put split-loom conduit over your wires. You will also want to put split-loom conduit over your wires. This will help protect them during installation and during their lifetime in your coach.
The battery post was already full so, fortunately for me, my batteries have both threaded and standard posts. This allowed me to use a marine terminal adapter to add an additional threaded post for connecting the positive wire from the inverter.
Connecting to the coach
Instead of purchasing another transfer switch, which I may still do in the future, I opted to install a 30A outlet in the inverter compartment. To use the inverter, I will simply plug-in the coach using its shore power plug and a 50A-to-30A adapter. Since I will be using the shore power plug, I need to be careful to turn off the converter (the charger) when running the inverter. I am looking into an A/C coil relay that would turn of the converter when the inverter is powered. The nice folks over at DIY RV have a great article with this concept in it.
The control panel
The remote panel for the inverter needed to be mounted inside the coach. This enables me to monitor the input and output power as well as turn it on and off without having to go out to the compartment. This was a simple matter of running the remote control wire from the inverter to remote panel. Of course the day I decided to do it was the day I forgot all of my cable running tools. So I ended up improvising and using a sturdy 30′ tape measure as a fish tape.
Finishing up and testing
During testing I found that I hadn’t crimped the ground wire connection well enough and it came loose inside the inverter. Once that was corrected and everything passed, we geeked out over microwaving a cup of water while sitting there not connected to any shore power. It’s the little things in life, eh? Now were all set for some boondocking though we still need to add solar to complete the cycle.