Now that summer is in full swing, I was extra motivated to do some electrical work and get my ventilation system going. No more sweating like a pig at a bacon festival.

I’ve got the batteries in the helm, and they’re connected up to the Renogy Rover 40A MPPT solar charger/controller. The Rover is the black box that I temporarily mounted above the helm on the right. That’s connected to the four 100W panels on the roof with 8 AWG cable. Then the two FanTastic Vents are connected directly to the 12V load terminals on the Rover.

And that makes a self-sufficient off-the-grid system, using solar energy to charge the batteries and the batteries to run the fans. The fans are super smart, too. They have thermostats and rain sensors that can open and close their domes automatically. So as soon as the sun heats things up to 72°, the fans kick on. As it gets warmer in the afternoon, the fans speed up. And some time after sunset when things cools down, the fans slow down and turn off. And if it should rain, the fans will turn off and the domes will close by themselves. Pretty sweet, eh? And yes, they work manually too.

The next big challenge was to figure out how to mount the ProMariner 2000W Pure Sine Wave Inverter safely inside the helm — with the key word being ‘safely.’ So here’s what I came up with:

I drilled four 3/4″ holes in the sides and inserted two pieces of 1/2″ EMT conduit. I later ‘capped’ the ends of the pipes on the outside to keep them from slipping out of their holes, as they did repeatedly when I tried to wrangle the 45-pound inverter through that hole.

And here’s the result. The inverter is straddling the pipes about two inches above the batteries. The inverter can slide left or right depending on which end I need to access. I’ll also try to remember to put a strap around it before I drive off anywhere.

Now normally you’re not supposed to put electronics inside a battery compartment. But remember, these are sealed AGM batteries, not flooded lead-acid. So they should emit no combustible gasses. And just to be sure, I will be cutting plenty of ventilation holes in the helm and installing a fan if necessary. It probably won’t be necessary because the inverter has a fan on one end already.

The helm’s hatch hole seems to provide ample access to the backs of the AC/DC panels. I won’t be using the hatch cover that came with the helm itself. I’ll be having one made custom at TAP Plastics later. And yes, it will be cool because it’ll be the first thing you see when you step up into the RETROvan.

One nice thing about my floorplan is that when working inside the helm, I can just sit on the steps and everything’s at eye level. It’s also nice that none of these powerful electronics take up any valuable cabinet or storage space.

I also installed a Blue Sea Systems USB port to power the helm’s iPad mount. And there’s now a Blue Sea Systems 200 Amp ANL fuse block mounted just above the inverter, on the inside.

Now comes the hardest part: Wiring up the AC/DC panels. For this I got 100 feet of Ancor 12/3 marine grade cabling for AC, and 100 feet of 12/2 to go along with the 100 feet of 16/2 I had already bought for speakers. I’ll have to make all my own terminal connections, so I ordered a Wirefy kit with hundreds of assorted heat shrink connectors.

Now if I could only follow the wiring diagrams for the panels, while still incorporating the inverter. The diagrams seem to omit important information, like what size main fuse to use. I might start with the DC side because it’s a little safer. But I have done plenty of AC work inside our house. The one thing I’m sure of in the RETROvan, is that the Marinco 120V Shore Power Inlet will connect directly to the dual-pole main circuit breaker on the AC panel first. And from there to the AC input side of the inverter. But the fun place to start would be the backlit analog gauges. Because then I can see things coming to life as each circuit is connected.

Oh, I almost forgot. Those massive red and black cables pictured above are 2/0 AWG. I bought them pre-terminated in three sets, made by WindyNation. 1-foot, 2-foot and 3-foot. I used a red 1-footer as the jumper between my two 6V batteries. I used a red 3-footer from battery + to the 200A fuse block, and then a red 2-footer from the fuse block to the inverter +. The negative side is simply a black 3-footer from the battery – to the inverter –. So that means two black cables go unused, but that was a lot less stress than trying to cut and terminate my own battery cables which are 70mm in diameter and stiff as hell. But in the end, they all seem to fit inside the helm without kinking or tying in knots, much like your lower intestines. The trick was to dry fit everything before connecting anything.

There was one moment of terror when I disconnected the 8 AWG battery cables from the Rover but forgot to disconnect them first from the batteries, and then they both touched the bare diamond plate floor.

To quote Dustin Hoffman in Rain Man: “Sparkly.”