Solis Pocket Charging on Shore and Solar

[SSJ_7YL3R]

Hello,

Here is a description of my goal:

I have a Lifepo4 battery generator I use while off grid, and I am wondering if there is a way to make my Solis Pocket more usable while off grid.

I want to plug my generator into my 30A receiver using a dog bone in order to provide full auxiliary power for the DCs, USBs, and 110V plugs. My generator is strong enough to do this, but I want to utilize my solar panel on top as well.

My thought was this: Plug the generator into the 30A, and then plug my generator's charger into one of my DC plugs in the RV.

My hope would be that while I provide power to the RV (and RV batteries), I would also be able to charge/circulate power to the generator, hopefully adding additional power from the solar panel on top.

I know there would be efficiency loss in the process, but ultimately if I am light on power usage, I would still get a net positive if I had strong solar input. The possible flaw I see in this process would be that when I am plugged into the 30A, the solar doesn't charge the batteries, or divert power to the DC outlet as it typically would when not plugged in.

Am I crazy for considering this? Or would this allow me to power everything and utilize my top solar panel for charging my generator?

Thanks in advance!

[creativepart]

NOPE!

This is not possible. You don’t have a generator, no matter what marketing terms they put on it. It’s a battery. You are not generating power you are storing it to use later. You can’t plug your battery into that same battery to charge it. If you could you would have discovered fusion.

[SSJ_7YL3R]

Originally Posted by creativepart

NOPE!

This is not possible. You don’t have a generator, no matter what marketing terms they put on it. It’s a battery. You are not generating power you are storing it to use later. You can’t plug your battery into that same battery to charge it. If you could you would have discovered fusion.

Haha I see what you're saying, but I think you've misinterpreted my post. The house batteries on my Solis and my generator are two different things. Typically, when not plugged into 30A, the RV batteries run my USBs and 12V DC plugs, but will not run the 110 AC outlets. So, as a separate piece of equipment, I have a battery/inverter (generator) that I use to power my heavier appliances off grid.

My question was if it was possible to use the 12V DC plug my RV naturally allows me to charge my other battery, whilst having that battery plugged into my 30A. This would allow me to use my 110 ACs in the RV, without having to plug into my generator.

Essentially, I want my top solar panel to charge my RV batteries, run that power through the 12V into my external battery, and then run that power into the 30A.

My concern would be that the RV batteries won't run the 12V, but instead draw the power for that 12V from the external battery, and bypass the RV batteries altogether. If that were the case, then there would be no point, because I'd basically be running a single loop using only the external battery.

However, if the RV batteries are still being used to power my 12V, even while the 30A is plugged in, then I could use the RV battery in combination with my top solar panel to put power into the external battery, and use what I need from that. If I over use my intake, my external battery drains, but if I have light usage, then ultimately my external battery would receive charge via the top solar panel, to the RV battery, through the 12V to the external battery.

Does that make more sense?

If the RV battery switches off when plugged into 30A, then my goal is a lost cause, but if the RV battery is still powering the 12V, then in theory it seems like it should work.

[creativepart]

I tried to respond to this a number of times and keep getting wrapped in a circle. I think the problem is that you wish to treat your "battery generator" like a gas powered generator - which it is not.

Perhaps it will help to explain how your RV and batteries work when plugged into shore power. When you are plugged into shore power (or generator, any outside 110v AC) this powers your RV's converter/charger. The converter (not your house batteries) powers all of your 12v AND at the same time it also charges your house batteries.

So... you'll be using your outside battery to invert it's stored 12VDC to 110v AC only to then convert it back to 12VDC via the RV's converter and the losses will be much greater than the output and you will just lose more power.

Unless... I still misunderstand what you are planning to do. Which is possible.

PS. Oh and solar doesn't really do much here. It's connected via a charge controller directly to your house batteries as an means of charging the house batteries.

[SSJ_7YL3R]

Originally Posted by creativepart

I tried to respond to this a number of times and keep getting wrapped in a circle. I think the problem is that you wish to treat your "battery generator" like a gas powered generator - which it is not.

Perhaps it will help to explain how your RV and batteries work when plugged into shore power. When you are plugged into shore power (or generator, any outside 110v AC) this powers your RV's converter/charger. The converter (not your house batteries) powers all of your 12v AND at the same time it also charges your house batteries.

So... you'll be using your outside battery to invert it's stored 12VDC to 110v AC only to then convert it back to 12VDC via the RV's converter and the losses will be much greater than the output and you will just lose more power.

Unless... I still misunderstand what you are planning to do. Which is possible.

PS. Oh and solar doesn't really do much here. It's connected via a charge controller directly to your house batteries as an means of charging the house batteries.

Okay I think you are answering my question here.

Essentially by using any power source to plug into the 30A recepticle (External battery, generator, shore power, etc.), the RV will do this: Power all outlets (USB, 12V, 110AC), and charge the house battery.

Which means that the house batteries would not be tapped to power the 12V, but instead power for those would be drawn directly from the source connecting the 30A. Which also means that I would be using my external battery to refeed itself through the converter of the RV, resulting in unnecessary loss.

My hope was that the USBs and 12V would still be powered by the house batteries, and those would continue to be charged by the solar, creating something like this:

Solar > House battery > 12V DC > External battery

And then ultimately from external battery back to 110AC via the 30A.

But it sounds like the RV is likely setup to bypass use of the house batteries when connected to 30A, so it is not possible. Is that correct?

[SSJ_7YL3R]

Are we 100% certain that the flow when connected to 30A isn't like this:

30A > House Battery > 12V

Essentially still using the power source of the 30A, but continuing to run through the house batteries? In this case, the house batteries would stay at full charge, since they have a direct charge source, but still be wired to run the USBs and 12V. Or is there some kind of switch that is triggered when plugged into 30A that diverts power draw directly from the 30A, with 0% taken from the house batteries?

Sorry I'm just trying to be thorough lol

[creativepart]

You got it now. RVs have had converters for decades and this is how they've always worked.

The only time this isn't true is when you have an inverter/charger instead of a converter/charger.

In an RV with an inverter/charger the 12vdc always comes from the batteries even when plugged into shore power. The 110v shore power bypasses the inverter to power the AC appliances AND it has a separate charger that charges the house batteries - but that charger can be turned off.

In an RV with a converter you don't even need any batteries when on shore power. The converter will handle all 12vdc power needs.

[creativepart]

Originally Posted by SSJ_7YL3R

Are we 100% certain that the flow when connected to 30A isn't like this:

30A > House Battery > 12V

Yes, we're certain.

In fact it's like this:

30A > 12V <> House Battery

The converter's 12vdc output is connected directly to the power center's 12vdc buss. So, is the battery's output. So, on shore power 12v is powered by the converted shore power and when no shore power is present the batteries energize that buss. (This is simplified and leaves out the battery charger in between the converter and the house battery.)

[SSJ_7YL3R]

Originally Posted by creativepart

Yes, we're certain.

In fact it's like this:

30A > 12V <> House Battery

The converter's 12vdc output is connected directly to the power center's 12vdc buss. So, is the battery's output. So, on shore power 12v is powered by the converted shore power and when no shore power is present the batteries energize that buss. (This is simplified and leaves out the battery charger in between the converter and the house battery.)

Brilliant. Thank you for the knowledgeable, and thorough answers my friend!

[Winterbagoal]

Can you run a charging line from a 12VDC coach battery outlet, to your external lithium generator pack to charge it at 12VDC from the solar panels/charge controller? Like via a USB connection or something?
The coach batteries will be charged by the van's solar charging system, on a good sun day you might get 1A of charge current for every 20W of panel, and might be able to support/offset the draw down from the external generator, when the van's 30A shore power cable is plugged into it, as long as it's a bright sunny day.

The problem others have had that have tried something like this is, when you plug the van's 30A shore power cable into your external lithium generator, the van's converter/charger will see the "pretend" shore power, and start to try to charge the coach batteries with it, and that may divert a lot of the lithium generator's 120VAC power away from the van's 110-120VAC outlets. I believe those folks have disabled the converter/charge at the breaker panel, and that might solve that problem for you.
Beyond this theoretical speculation, you might want to just try it. It's up to you to decide yay or nay. We assume no liability for any unforseen problems it might create, downstream.
Also search the net for threads by others that have tried similar setups to what you want to try. I assume the object is to power up the 110-120VAC outlets in the van when no shore power is available to do it normally. Most others that I'm aware of, have tried plugging their 30A shore power cord into their coach batteries, via a hgih capacity inverter, with capacity over 1000W. As with anything "off the wall" like this little project, do your homework first.
Good luck.
(any other questions/comments, send me a message)

[joda]

i'm doing something like this in a Solis 59P.



First, the solar charge controller in the Solis isn't very efficient. Win installs a PWM (pulse) charge controller - I guess to save a little $ I replaced it with a SolarBoost 3000 MPPT (maximum power point tracking) controller. Any MPPT is more efficient at charging batteries than a PWM.



The SB I installed has a connection to send power to a second device once the primary battery is fully charged, so I can wire that to the Battery/Inverter's (BI) DC input, So solar power goes to the BI after the RV batteries are full instead of going to waste.



When I Feed AC power back in the RV from the BI, I turn off the circuit breaker for the RV's power converter so the BI is not wasting AC power on the converter - it only powers the other AC circuits.


I hope this makes sense. It is a bit complicated to describe without a diagram.

[joda]

For clarity, what you're calling a "LIFePo4 generator" or external battery, I'm going to call a "portable power unit" ;-)



With regard to this point:

My concern would be that the RV batteries won't run the 12V, but instead draw the power for that 12V from the external battery, and bypass the RV batteries altogether.

The portable power unit won't "feed" back 12V from it's 12v charging port into the RV.

The 12V loads in the RV will take power from the house batteries. The only way to draw 12V out of the portable power unit is from it's 12V/USB output ports.


Plugging the Power Unit into one of the RV's 12V ports, even while it provides AC into the RV, will work to move some of the collected solar power from the house batteries into the Portable Power Unit's battery.



I do this also, and it works as you expect.