1976 GMC Motorhome

This is an excellent topic. Really interesting project 8)

Back right corner.....

Now I know where to aim my rifle.

Thanks!

Lol nice work

Flugtechnik said:

Back right corner.....

Now I know where to aim my rifle.

Thanks!

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Either there or lower middle of the body, there's 40 gallons of gasoline and 40 gallons of shit down there, would make for quite the mess

I got the poo on me.

JustinLonghorn said:

I got the poo on me.

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It's just an old crapper tank people. It's poo!
May or may not have that movie accidentally memorized.

Sent from my XT1585 using Tapatalk

The next major hurdle was wiring this thing.
It's a little more complicated than a bike.

I've got 3 different power sources, Generator (120) Shore Power (plugged in 120) and Battery power (12V).
The 120V feeds a converter, which converts 120 AC to 12 DC.
The Battery Feeds an Inverter that converts 12 DC to 120AC.
And I wanted the shore and generator to switch automatically so I don't have to go flipping breakers to switch from one to another.

A problem a lot of people face is if the inverter is connected to the same circuits as everything else then when it's running your converter is also running unless you turn it off. This means you are using battery power to charge your batteries. Not a good plan.
So I started with that. I put it on a separate circuit that is connected to a transfer switch. If plugged in to shore power or the generator is on the switch bypasses the inverter and powers directly from the 120, saving the batteries. If the shore power and generator arent in use, the switch switches to the inverter to power the things I want powered by 120 when not plugged in (stereo, TV, and a couple of outlets). Pretty slick.

The generator and the shore power are both connected to an auto switching transfer switch, so power comes from whichever is putting out power (the transfer switch is just a few high power relays).

Diagram below:


To make all this work I had to modify the breaker box to have 3 separate parts, so I cut the connectors and epoxied it back in place, easy.


Here's what it looks like put together without any wiring


Next was wiring and plumbing.
I decided to go with a tankless water heater, because I like long showers, when not hooked up I can take short ones, but when hooked to shore water with the tankless heater I can take as long as I damn well please!

For the wiring I so far have used 500 ft of 14ga primary wire, 50 ft of 4 AWG welding wire, and 100 FT of 6 AWG welding wire.
The primary wire runs all the DC circuits, mostly for the LED Lights and the vent fans.
The 4AWG fruns from the battery bank to the inverter, the generator, and the DC distribution panel/converter.
The 6AWG runs from the battery bank to the solar charger, to the engine battery and eventually to the solar panels, I haven't gotten that far yet though.

This is what that fucking mess looks like:



The spray foam will cover most of it up.

And besides a lot of little stuff that I won't bore you with, that's pretty much where we sit at present.
I hope to cut an opening for a vent fan in the bathroom, and hopefully get some foam sprayed this weekend.

How thick are the wires on the shore cable? What kind of circuit protection do they have?

Electric tankless water heaters (for home use) generally pull well over 100A. They often require three 8AWG hookups spread across three 40A breakers.

Sonreir said:

How thick are the wires on the shore cable? What kind of circuit protection do they have?

Electric tankless water heaters (for home use) generally pull well over 100A. They often require three 8AWG hookups spread across three 40A breakers.

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The shore cable is 6AWG, but the water heater is propane powered, forgot to mention that!
Wired to a 50A breaker

I love those propane water heaters. My old man has one at his getaway shed.

Very nice work mate. Good to have you back.

Brodie said:

I love those propane water heaters. My old man has one at his getaway shed.

Very nice work mate. Good to have you back.

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Thanks Brodie,
I haven't tested the heater yet, I hear they are a bit finicky. The plan is to set it to the shower temp I want and then just have an on off valve in the shower.

SONIC. said:

Thanks Brodie,
I haven't tested the heater yet, I hear they are a bit finicky. The plan is to set it to the shower temp I want and then just have an on off valve in the shower.

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Do you live in a climate where you are going to have to winterize it so your pipes don't freeze in the winter? If so you are going to have to add in a 3-valve isolation piping system around your water heater so you can isolate it when you run the antifreeze into the lines. You don't want to put that stuff into the heater. It gets isolated and then just drained.

ridesolo said:

Are you adding the 12v to 120v inverter? The reason I'm asking is that most RVs I've seen usually go the other way; 120v to 12v. This keeps your house battery charged when you are plugged in and most of the interior lighting is usually 12v so they work when you're on the road or dry camping. While on the road the engine charges both the chassis battery and the house battery but the chassis battery is isolated from the house circuits so using your house 12v power doesn't run down the chassis battery and leave you stranded. I noticed you said earlier that you will be using 4 batteries. I'm assuming these are all house batteries, are you going to use four six volt batteries for your house battery set-up?

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The inverter is so that I can run the TV and stereo and use an outlet while I am out in the middle of nowhere without running the generator. It is added on, not that any of this is stock haha.

The house batts will also be wired to the alternator as you described.
Yes the house batts are 6v deep cycle wired in series for 12v.

The plan is to not use antifreeze, I'll use compressed air to blow out the lines for winterizing.

SONIC. said:

The inverter is so that I can run the TV and stereo and use an outlet while I am out in the middle of nowhere without running the generator. It is added on, not that any of this is stock haha.

The house batts will also be wired to the alternator as you described.
Yes the house batts are 6v deep cycle wired in series for 12v.

The plan is to not use antifreeze, I'll use compressed air to blow out the lines for winterizing.

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Understood, sounds good. In my trailer the TV is 120v so if we were dry camping TV is a no go... wouldn't bother me, but the Mrs would revolt! My van had a 13" analog TV and a VCR, both of which were pretty much useless, like new, but useless. It's got a shore cable, house battery, and the whole set up, but I was able to find a 19" digital TV w/ DVD (less than $100) that uses 12v as its primary power so it was an easy switch-out for the original. In my searching I found several TVs and stereo units that were 12v.

Yep, my old man has a 23" 12v TV with dvd. Bought it new for cheap.

It is funny how close offgrid sheds and motorhomes are to each other.

12v led lighting will save on a heap of power as well. And the few at the shed are bloody bright.

Brodie said:

Yep, my old man has a 23" 12v TV with dvd. Bought it new for cheap.

It is funny how close offgrid sheds and motorhomes are to each other.

12v led lighting will save on a heap of power as well. And the few at the shed are bloody bright.

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My van and trailer have been converted to 100% LED lighting on the 12v circuits, both the house and chassis (except the headlights on the van). I've used several different kinds depending on the application, but found an eBay vendor (autosaver88) who has great prices and ships really fast from the US west coast. We've been really happy w/ the results.

Since you guys mentioned it haha.
The lighting in this one will be all LED, with a warm white color temp as opposed to the classic LED blue.
I couldn't find any that I particularly liked in the states for the price I wanted to pay, so I placed an order straight from china for 200 of them 8)
I kept 30 and sold the rest to other gmcer's. They are pretty sweet, 4 watts each and the light color is great.





With the battery power I am going to have and the ridiculously low draw of the LED's (.2 amps apiece when I tested) I should be able to leave the lights on for several days straight and still have battery leftover. Coupled with the solor and the generator I shouldn't ever have a problem with power 8)

And yep Brodie, this one is basically meant to be a mobile off grid hideaway/weekend warriormobile.
I got it so that I could toss some bikes on the back and drive 4 or 5 hours on a friday night, spend all day sat and sunday playing and then drive back sunday night, all for a few bucks of gas.
As cool as it sounds to strap everything to the ADV bike and go camping, it's really not feasable (or pleasant) with a significant other on the back.

Wait until you add wee ones to the mix. Ha

JustinLonghorn said:

Wait until you add wee ones to the mix. Ha

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I don't now how the hell some of you guys manage! My hats off to you for sure