Sprinter van: Electrical system stuff

I realize I didn’t actually show much of our electrical components in our installation post. At that point, all of the components were essentially dry-fitted. Meaning nothing was actually installed for real. First, we had to start installing the wall panels. Which meant drilling, filing, and painting a lot of holes for rivnuts. Once we got to that point, the panel that held all of the electrical stuff could finally be installed. So here are some photos, starting with all of the components tucked neatly under our bed (and the 12V Ikea Dioder strip lights we used for our granddaddy electrical test and that now illuminate our garage area). 

Worth noting: At bottom right in the photo above is a battery tender we picked up from Costco years ago for ol' Stuart when we had to recharge his starter battery every once in a while (we rarely drove him, which is why earlier this year we finally sold him). For the van, we just always leave that thing clipped to the positive and negative battery posts on our house batteries. It keeps the batteries topped off and healthy without ever over-charging or doing any damage. In fact, not using one would severely reduce the life of our two AGM batteries.

Back to the system… I ended up redesigning the electrical layout about 3.46 million times. In its current state, both the DC-DC charger and the inverter are mounted inside the wheel box. 

I’m really happy I ended up doing that. They’re out of the way but still accessible. I had double- and triple-checked the jumper settings on the charger matched the voltage stage requirements of our Windy Nation AGM batteries. 

I then used a combo of zip ties and cable clamps I had in my electrical stash to tidy up the cables.

Grounded the inverter and negative bus to the contact I made just behind the wheel well. 

Hooked up the battery temperature monitor to the charger. Plugged in the 15A grounded cable  to the inverter I made from a $4 plug and leftover cable I had from when I wired a new 3-way switch in our garage. 

Then called all of that good. Time to work on the rest of the components.

Having reconfigured the placement of the charger and the inverter, I had to do the same to some of the stuff on the panel. That meant placing the 50A ANL fuse coming off the charger and the 50A breaker on the fuse panel in some pretty tight quarters. 

Essentially, the 4-gauge cables coming from the engine compartment go into the charger, and 8-gauge cable comes out and into their respective bus bars (positive and negative). The positive from the battery bank goes directly into a 300A master kill switch (which turns the entire house system on and off), while the negative goes directly into the battery monitor shunt. The shunt then measures all the loads so the monitor, mounted above our kitchen countertop, can tell us how many amp-hours remain, along with the battery voltage and draw (in both amps and watts). It’s pretty sweet.

The 100A breaker on the inverter acts like an on/off switch since A) we can’t reach the inverter’s on/off switch very easily and B) we don’t leave it running all the time because it draws about 1A of power just being powered up. We primarily use it in the morning for boiling water in our 700w tea kettle and steaming milk with our 700w Aeroccino. The 50A breaker off the fuse panel is great for killing all of our loads with the flick of a switch.

I was admittedly a little worried with all of those components essentially hanging out, screwed to a panel. However, with the bed installed and as that first photo shows, they’re basically tucked up right underneath it. Out of the way but still accessible if needed. It’s actually a pretty awesome layout. Not without its trials and tribulations, but in the end yes, pretty awesome.

The final puzzle piece was laying out and installing the components above our kitchen counter: a trio of switches (the bedroom lights, the under cabinet lights, and the 3-way galley lights), a 12V socket and a USB charger, the 120V GFCI outlet off the inverter, and the battery monitor.

For the inverter cable, I bought a $4 plug and wired it to a length of 12-gauge conductor I had leftover from a garage project. It was just the right length. 

Rather than installing a fuse for the only 120V supply, I went with a GFCI outlet. It would act as a fuse, if necessary, and trip before doing any damage to the inverter. The 3-way SPDT switch ended up being a little funky. We have a switch on the galley cabinet just inside the slider door and the other above the opposite counter. It works, meaning we can switch on and off the galley lights with either switch, but in order for the lights to be on both switches have to be in the same ‘on’ position. Since they work and we had a million other things to do, I haven’t circled back to check if that’s correct or not. I’ll get to it. The other components were all straightforward. To test the 120V outlet, I fired up the inverter and ran our tea kettle. No issues.

Next up: Plumbing…