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Going off grid.

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I have a tangential question. I keep reading that I need a DC to DC charger. Why can't I just wire the second battery to the alternator? At this point I'm just talking about in the tow vehicle in case that matters like if the issue is current loss over the distance to the trailer
Because!!!
How did you like the answer?

The more technical answer is wire length, resistance, different batteries or age. But assuming you start with identical batteries, at identical age, resistance would be the failure..furthermore the thought all batteries will be replaced at the same time is highly unlikely!! So forward thinking would dictate a plan.

But there's more! DC to DC converters are designed to limit current, and that explanation is the winner!!

Each battery location has the equivalent of an individual battery charger set to battery specifications, so each battery can be charged optimally.

So in summary!

Each bank no matter its location gets personal attention!

Because you can set the load you can protect the alternator.

Because the regulator only sees a load rather than battery charge and the fact that you can protect the alternator from excessive outputs, you can tweak the proformance of the alternator and get the most out of it.

Warning:

The chassis battery still needs protection to keep it from draining.


Hope that answers your questions!!!
 
Because!!!
How did you like the answer?

The more technical answer is wire length, resistance, different batteries or age. But assuming you start with identical batteries, at identical age, resistance would be the failure..furthermore the thought all batteries will be replaced at the same time is highly unlikely!! So forward thinking would dictate a plan.

But there's more! DC to DC converters are designed to limit current, and that explanation is the winner!!

Each battery location has the equivalent of an individual battery charger set to battery specifications, so each battery can be charged optimally.

So in summary!

Each bank no matter its location gets personal attention!

Because you can set the load you can protect the alternator.

Because the regulator only sees a load rather than battery charge and the fact that you can protect the alternator from excessive outputs, you can tweak the proformance of the alternator and get the most out of it.

Warning:

The chassis battery still needs protection to keep it from draining.


Hope that answers your questions!!!
Very helpful, thank you
 
I'll just leave this here as a reality check.
 
I'll just leave this here as a reality check.
Wow! breitbart is just as trustworthy as an information source a fox news. (n)
 
I'll just leave this here as a reality check.
Was gonna put up the articles but I've put up my opinion more than most can tolerate!!! Love and reality never have been a good mix
 
Simmer down folks and let's keep on topic and not news, opinions, media, etc.
 
So, my tow vehicle is 24 volt but the trailer is 12. Could I use one 24-12V to charge batteries in both?
 
So, my tow vehicle is 24 volt but the trailer is 12. Could I use one 24-12V to charge batteries in both?
Yes you can use a DC to DC converter to charge the house batteries. I would change the running lights and brakes to 24v.
 
So it turns out the guy at the dealership didn't know what he was talking about, the trailer is also 24 volt. Everywhere I look 24 volt batteries are ridiculously expensive. Can anybody recommend a good vendor for these?
 
Lets go back to your first post. You say you have an Econoline E350, so do I but mine is 30 years old. How do you come to have a 24v system in it? And I have never seen a 24v production camper. It seems you are talking about a solar system in your 350? In your trailer?
 
Lets go back to your first post. You say you have an Econoline E350, so do I but mine is 30 years old. How do you come to have a 24v system in it? And I have never seen a 24v production camper. It seems you are talking about a solar system in your 350? In your trailer?
The E 350 is a bus conversion with a wheelchair lift, hence the 24 volt. The trailer I have no idea why but it came with a 24 volt battery. It's a 2023 Coleman light. I'm planning to do solar. I've ordered 400 watt panels for both along with charge controllers. The trailer came with a 24v 88 AH battery. That should be good for the bus, but I'm looking for 300 AH for the trailer
 
Almost nothing else in that bus is 24 v. So I don't think the main power is 24v. If the wheel chair lift uses 24v by pulling from 2 batteries in series that does not mean everything else is running on it. Check voltage at any bulb in the lighting system. Check it at the hitch plug. I don't think Coleman has ever made a 24 volt camper. They make campers exclusively for Camping World.
Please show me a picture of this battery.
 
The bus only has one battery, a 24 volt. Here's the battery that came with the trailer
 

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The bus only has one battery, a 24 volt. Here's the battery that came with the trailer
Typically two 12vdc batteries are connected in series, for 24volts. If lithium is your desire be sure the BMS will work with 24volts. If you choose lead, may I suggest Northstar Blue+ batteries. I sourced mine from Northern Arizona Wind and Solar. They too, are expensive, but the cycle life of its carbon lead technology leaves lithium in the dust! They come with bus bars to connect them in series.

The math told me at time of purchase put them inline with QUALITY AGM BATTERIES. Oops had the cap button on, to lazy to fix it!!! Now I was in the market for a new 12v battery and went shopping, only to consider other options, the prices have gone through the roof!!! So telling you what technology holds the best deal in the current market, only the powers pushing technology can tell!
 
That is a group size designation.......It is not 24 volts DC. Put a meter on it.
IF you replace and can fit it in put a 27 in.
 
The dimensions for the Northstar Blue can be found here


I use the blue+ and was willing to accommodate the form factor. I use the 190s and they are setup as 24 volt system. My system consists of two batteries making 190 amps of storage.
Household fridge and freezer are what I limit my usage to on cloudy days in AZ and run the charger when needed. In the last year I had to drain the old gas before running it because 6 or more months go by between it's need.

My solar is considerably larger than what you plan, and that makes a big difference, however you should be fine with 800 watts.

The big difference would be I can use electric appliances during the day without the batteries taking a hit! Actually my controllers go into bulk charge mode when I use high use loads. So at the end of the day my batteries have a higher state of charge!!!


If you are planning to increase your bank, then plan as well, for different form factor batteries. Also look at the PDFs at the link above.

My daughter who lives off grid in Florida, was using these batteries for 4 years when she told me about them 3 years ago. She still has no problems with them, and I wouldn't replace them with anything else.
 

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