How is my electrical diagram?

[Tom&Shelly]

We keep an inverter in our tongue box, but I can't recall what we've used it for. It's been a long time since I dug it outta the box. I'll be curious to read other's thoughts on it.

Tony

There aren't a lot of things these days that only require the energy in a teardrop size battery that are just made to run off of 120 vac. Since there is a conversion loss in the inverter it's usually more efficient to buy the 12 volt version.

Of course, if someone doesn't want to buy the 12 volt dc version, an inverter may make sense.

Tom

[italianub]

Yeah I agree about the coffee... but unfortunately I am not the boss when it comes to that (I don't even drink coffee!) so I have to appease the better half hahaha.

I will definitely check out about getting a 12volt cord for the cpap, I'd love to not need an outlet inside the cabin!

[Tom&Shelly]

Yeah I agree about the coffee... but unfortunately I am not the boss when it comes to that (I don't even drink coffee!) so I have to appease the better half hahaha.

Well, the physics says you may not be able to do it. Your battery holds so much energy, and it takes so much to make hot water. The inverter can only pass so much energy through it at a time.

Bruce Osborn, on this forum, built a humungous electrical system that he says was motivated by the desire to heat a mug of water. (Please correct me if I remember that wrong, Bruce.) But that's his hobby and there is a considerable amount of space devoted to batteries and the electronics necessary to keep them happy.

Edit--(After a cup of coffee): OK, I do see a 600 watt coffee maker on the market. No idea how good that is, and it is the lowest wattage of the coffee makers I've seen. Most are around 1300 watts. My guess is your wife may be disappointed.

So, keep in mind a 600 watt inverter will take a 50 amp input from the 12 volt battery. That will require some hefty wire (depending on the distance from the battery). You'll need to size the fuse box and other components with that in mind.

Tom

[tony.latham]

Bruce Osborn...built a humongous electrical system...

And he does that kind of stuff for a living. When Bruce says something about electricity, I listen. He's been a big help for me.

Tony

[italianub]

Yeah I agree about the coffee... but unfortunately I am not the boss when it comes to that (I don't even drink coffee!) so I have to appease the better half hahaha.

Well, the physics says you probably will simply not be able to do it. Your battery holds so much energy, and it takes so much to make hot water. The inverter can only pass so much energy through it at a time.

Bruce Osborn, on this forum, built a humungous electrical system that he says was motivated by the desire to heat a mug of water. (Please correct me if I remember that wrong, Bruce.) But that's his hobby and there is a considerable amount of space devoted to batteries and the electronics necessary to keep them happy.

For grins, I could try going through the numbers (after I've had my coffee!) I don't want to sound pessimistic, but facts are facts.

Tom

Yeah, I get it, but I have to keep up appearances that I'm trying

[Tom&Shelly]

Yeah I agree about the coffee... but unfortunately I am not the boss when it comes to that (I don't even drink coffee!) so I have to appease the better half hahaha.

Well, the physics says you probably will simply not be able to do it. Your battery holds so much energy, and it takes so much to make hot water. The inverter can only pass so much energy through it at a time.

Bruce Osborn, on this forum, built a humungous electrical system that he says was motivated by the desire to heat a mug of water. (Please correct me if I remember that wrong, Bruce.) But that's his hobby and there is a considerable amount of space devoted to batteries and the electronics necessary to keep them happy.

For grins, I could try going through the numbers (after I've had my coffee!) I don't want to sound pessimistic, but facts are facts.

Tom

Yeah, I get it, but I have to keep up appearances that I'm trying

Sure! There are many of us who need our cup of coffee in the morning, and have looked at this problem in regards to camping. Shelly and I have a 120 vac coffee maker we use when camping with shore power. For other times, we've tried presses and pour over systems but find them a pain to clean out.

I surprised myself that I can make percolated coffee that tastes really good (still requires cleaning out later of course, but the basket is wider than most other systems and the coffee isn't as compacted). So we're going to try that next time.

Just some other ideas to consider.

Tom

[Onajourney]

The one big thing I don't see is the 120V battery charger. Make sure you wire the 12v side before the main shut off so when you shut the main off, it will still charge when you plug into shore power. Same goes for the solar charger. I don't have a wiring diagram of what I did but this is it what it looks like.

[italianub]

The one big thing I don't see is the 120V battery charger. Make sure you wire the 12v side before the main shut off so when you shut the main off, it will still charge when you plug into shore power. Same goes for the solar charger. I don't have a wiring diagram of what I did but this is it what it looks like.

Do you mean a charger that uses AC plug to charge the battery? If so, I have one that will be in the trailer but not always connected, only when I have some shore power. If you mean something else, please explain (total electrical noob here!)

[bdosborn]

There aren't a lot of things these days that only require the energy in a teardrop size battery that are just made to run off of 120 vac. Since there is a conversion loss in the inverter it's usually more efficient to buy the 12 volt version.

I still run everything I can at 12V as it's always the most efficient. I consider the inverter in the van to be a total luxury; it's awesome for running the Keurig, induction cook top and a microwave. We even use it to for the water heater. BUT, all our essential services are 12V: fridge, CPAP, lights, diesel heater, TV, etc... We carry a small butane stove to back up the induction stove top if the battery is low. Everything else the inverter runs we can do without in a pinch. I wouldn't have added an inverter in the van at all except I wanted to try the all electric approach, the trailer that has propane and I haven't used the small inverter in it for about 10 years.
Bruce
P.S. The all electric approach is awesome but it's expensive, everything gets big quick!

[italianub]

Alright, new updated diagram, thoughts?

I might put a 120v battery charger in there as well for when I have shore power, but I already have the charger so I can just put it in if I decide to use it. Not pictured is the shore power plug that I will install, but not connected to anything except a power strip in the galley.

You guys are awesome. I start my build in 2 weeks!

[tony.latham]

Alright, new updated diagram, thoughts?

I don't know which battery monitor you have but my AiLi meter (that I really like) shows juice going in and out. So the shunt should also be downstream of the solar controller. Just run your negative to the negative bus bar.

The other thing, is that one cabin and one galley light works fine. Teardrop cabins are small.



Tony

[italianub]

I don't know which battery monitor you have but my AiLi meter (that I really like) shows juice going in and out. So the shunt should also be downstream of the solar controller. Just run your negative to the negative bus bar.

The other thing, is that one cabin and one galley light works fine. Teardrop cabins are small.

I ordered two of these monitors, one for in and one for out - should I return one? I didn't realize they could do both!

https://www.amazon.com/gp/product/B013P ... UTF8&psc=1

I am going to have two lights in the galley and two in the cabin. I know one should be fine, but my brain needs symmetry! hahaha

[bdosborn]

Typically the master switch only connects to the positive side of the battery. No need to switch the negative. Most people are putting a double pole circuit breaker between the solar panel and the controller. This breaker DOES switch the positive and negative wires.

Bruce

[tony.latham]

should I return one? I didn't realize they could do both!

I don't think they can do both–-and I tried them early on. This is the AiLi meter that does and I really like:

https://www.amazon.com/AiLi-Voltmeter-Ammeter-Voltage-Motorhome/dp/B07FGFFHC6/ref=sr_1_2?crid=HEX43MFQRFU8&keywords=aili%2Bmeter&qid=1706466878&s=industrial&sprefix=aili%2Bmeter%2Cindustrial%2C269&sr=1-2&th=1



You can set it for the amount of useable juice in your battery and it will read how many amps you have left, what percentage it is, and what the solar gain is at the moment.

Tony

[italianub]

redacted - got it figured out!