Factory solar

[switz]

We did a different approach and totally rewired the trailer so all outlets are powered by the inverter that is attached to a 600 amp hour lithium battery and nine 100 watt solar panels on the roof.

[daleyocum]

Originally Posted by switz

600 amp hour lithium battery and nine 100 watt solar panels on the roof.

Now THAT’s a system! One more advantage to having a +30’ trailer...more space for solar and batteries!

[uncle_bob]

Originally Posted by SilverWind

I believe your system's solar charge controller needs to have the capacity for all of your panels combined.

A&M Solar made a modification to the Victron Charge Controller in my 500 watt system to accommodate a supplemental portable solar panel.

In my case it is a ZAMP 160watt panel connected via the (Airstream factory installed) ZAMP connector on my 2017 25FB battery box.

Hi

With dissimilar panels all running at once, you are very unlikely to get the combined output of all of them .... The Zamp portables have a controller built in so they are even less likely to combine with a rooftop setup.

Bob

[uncle_bob]

Originally Posted by daleyocum

Now THAT’s a system! One more advantage to having a +30’ trailer...more space for solar and batteries!

Hi

Yes, it's a system. It's still incapable of doing air conditioning when it's really hot out. One way or the other you need to come up with the power for that if you camp in the places we do. Two AC running at the same time can barely keep a 30' cool in the hot sun. They run for *many* hours each day.

Bob

[franklyfrank]

Originally Posted by uncle_bob

Hi

If your batteries are lead acid, they go through a coupe of phases as they get charged up.

Step one is indeed gobble as much current as the charger can deliver. The big question always is - how much does this or that charger actually deliver. There are a lot of models out there that do not deliver "label" amps right up to full charge. (for some really good reasons ... ).

Next step is limited by the battery chemistry. The battery no longer gobbles current like crazy. The battery posts are now up to darn near whatever voltage the converter is putting out. The battery is not fully charged. Is this the 80% point or some other point? That depends on a lot of factors. One is just what we are going to call fully charged. ( = that could be the labeled amp hours or the actual capacity of the batteries at their current temperature).

After the taper charge part of the process is over, your fancy super charger may indeed drop into the "let's rev up the battery" phase. If it's doing something useful, you don't have 100% until that part if finished.

Best guess with most batteries is that you will be in some sort of low(er) current charge phase for several hours coming from a pretty dead battery. How long it would take your converter / charger to go into super charge mode is very model specific.

Bob

So my take away is that don't let your batteries run down more than 50% if you don't have an immediate source of power available.

Thank you for the information.

[daleyocum]

Originally Posted by franklyfrank

So my take away is that don't let your batteries run down more than 50% if you don't have an immediate source of power available.

Thank you for the information.

That's correct for lead acid. With lithium you can go down to 20% should the need arise.

[uncle_bob]

Hi

Well ... errrr ..... this is always going to be a "that depends" sort of thing.

With Battle Born lithiums you can run them down to "zero". What's zero in this case? Well it's the 100AH that the label says is their capacity. The BMS cuts out and stops you once you get too far down the discharge curve. Is that really zero? Certainly not, but it is > 100AH below full charged at normal temperatures.

Trojan wet cell T-105's have some really odd charge parameters for a lead acid. If you charge them per their instructions (which pretty much nobody ever does), they claim you can go pretty far down the discharge curve without major impact. Yes, we're talking about 40% full vs 50%, but that's still a pretty big deal.

Virtually all batteries have more capacity when they are hot than when they are cold. You can indeed get 125% of rated capacity crammed into some batteries if they are a bit on the hot side. Yes, when you cool them down the capacity drops again. Attach them to a load and keep them hot .... you will get the extra 25%.

Yes, it's complicated and you need to dig a bit on whatever batteries you happen to have.

Bob

[pcassedy]

This is from the frequently asked question section of Zamp's website:

3. Can I connect two charge controllers to the same battery bank (e.g. combine a roof mount system and a portable kit)?

Yes, two independent charge controllers can be connected directly to the battery as long as both controllers are set to the same battery type.

The charge controllers will not work properly if wired in series, one to the other.

[uncle_bob]

Originally Posted by pcassedy

This is from the frequently asked question section of Zamp's website:

3. Can I connect two charge controllers to the same battery bank (e.g. combine a roof mount system and a portable kit)?

Yes, two independent charge controllers can be connected directly to the battery as long as both controllers are set to the same battery type.

The charge controllers will not work properly if wired in series, one to the other.

Hi

You can hook them both up (just as the stock AS parts are both hooked up at the same time). They will not self destruct when you do so. They also will not damage the batteries. So far so good. The gotcha is that they also will not do quite what you expect in terms of charging the batteries.

Bob

[Renascence]

Forgive my solar ignorance, the learning curve is steep!
With factory solar can additional freestanding solar panels be plugged into the existing solar factory setup to add additional solar charging capacity?
Or is it better to start from scratch, with no factory solar, and build your own system based on your individual needs?
I realize this is likely a loaded question and has innumerable 'what ifs' but need to start somewhere with advice and input from experienced Airstreamers. Thank you.

[gator.bigfoot]

Originally Posted by Renascence

Forgive my solar ignorance, the learning curve is steep!
With factory solar can additional freestanding solar panels be plugged into the existing solar factory setup to add additional solar charging capacity?
Or is it better to start from scratch, with no factory solar, and build your own system based on your individual needs?
I realize this is likely a loaded question and has innumerable 'what ifs' but need to start somewhere with advice and input from experienced Airstreamers. Thank you.

It depends. How are you plugging them in. Do you have room in the factory controller for the additional cells. What is the voltage of the cells you are adding. Are they similar to the ones you already have. Etc.etc.

Best method is to add an additional controller close to the batteries and feed into it. Leave the factory setup alone, since it has too many limitations anyway.

[AirMiles]

Originally Posted by Renascence

Forgive my solar ignorance, the learning curve is steep!
With factory solar can additional freestanding solar panels be plugged into the existing solar factory setup to add additional solar charging capacity?
Or is it better to start from scratch, with no factory solar, and build your own system based on your individual needs?
I realize this is likely a loaded question and has innumerable 'what ifs' but need to start somewhere with advice and input from experienced Airstreamers. Thank you.

I would suggest building your own if you have some skills in splicing wires together and can keep positive and negative wires in order. Installing solar on newer Airstream's with the Zamp Rooftop Box and factory prewire is a fairly easy task with some electrical knowledge and the support from AirForum members who've done it before. You will likely get a higher quality installation with more wattage and you will have the skills to maintain the system if you install it yourself. A 400W solar installation can be self installed for less than $2,000.

If you choose to purchase the factory solar package, you could still improve that system by replacing the solar controller $300, upgrading the wires between the solar controller and busbars $20, and adding a couple of additional panels $500. This totals around $800 in addition to the cost of the factory solar.

We're here to help if you decide you want to install your own solar. I was intimidated by solar too at first, but found it was easier to install than I first anticipated.

[Renascence]

gator.bigfoot and AirMiles,
Thank you for the replies and advice. We like boondocking more than not. The information you mention about factory solar limitations was a concern of ours. I have read many of the threads about solar and have come away with one significant piece of information; if you want solar independence than a conversation with Lew Farber is needed. We do not necessarily need that much solar, I don't think, but we are learning. I will continue to read and learn and make mistakes and move on. Your advice and input will not be forgotten. Thank you, Jeff and Kathy.

[jbeach]

Wow! Do you ever contract out? I recently acquired a 1992 B190 van in which I need to replace house battery, but more importantly add as much solar as possible. I know nothing electrical and am not confident with the local RV dealers.

[TouringDan]

Originally Posted by Renascence

gator.bigfoot and AirMiles,
Thank you for the replies and advice. We like boondocking more than not. The information you mention about factory solar limitations was a concern of ours. I have read many of the threads about solar and have come away with one significant piece of information; if you want solar independence than a conversation with Lew Farber is needed. We do not necessarily need that much solar, I don't think, but we are learning. I will continue to read and learn and make mistakes and move on. Your advice and input will not be forgotten. Thank you, Jeff and Kathy.

I might suggest watching some Utube videos by Will Prowse. He seems to be very knowledgeable, enthusiastic and candid about solar, batteries and controllers.

We were all ignorant about solar at one time. I have learned a lot from the knowledgeable people on this forum. Thanks to all of you.

Dan

[Zeppelin2018]

So you have Two 80w panels on the roof, is it best to add two 80w Zamp portable panels so that the roof and portable are «*balanced*» or does it matter? Would there be issues if two 200w portable were added instead? Thanks

[dznf0g]

Size(watts) doesn't matter. However, they all should have very close output voltage spec.

Originally Posted by Zeppelin2018

So you have Two 80w panels on the roof, is it best to add two 80w Zamp portable panels so that the roof and portable are «*balanced*» or does it matter? Would there be issues if two 200w portable were added instead? Thanks

[Overstreet]

Originally Posted by uncle_bob

Hi

As I drive around the country, there are a *lot* of RV parks with great big water slides and multiple other "attractions" right on site. ........., I am at a bit of a loss to see the benefit. We all get to do it our way ....

Bob

My daughter and her family with small kids to teen agers and her adult friends with kids like the parks with the water park, activities, haunted houses, ATV trails, fishing, etc. I can see the attraction. But don't stay longer than a day or so to visit. Then it is off to the park with better kayak destinations. We all have our preferences and reasons.

On the solar and the OP post....... on the 2019 at least he has 240watts. I only have 160watt but it seems to handle our needs. The OP should experience the system before worrying about it.