Portable Solar Battery Charging

[pjmarkham]

2017 Airstream FC 25 RBT. 2 interstate Marine/ RV SRM 24 Deep Cycle Batteries.

I keep my trailer in a storage lot with no access to electricity and I am trying to figure out the best way to keep my batteries charged. I've considered purchasing a generator but I understand that takes a long time to charge batteries and therefore is impractical for me. I've tried hooking up my truck periodically to refresh the batteries but that does not seem to work well. So now I am considering a portable solar panel. However I need advice on how many watt panel I would need to just keep my batteries charged. I have a storage spot with fairly good access to the sky so I should get good solar rays most days. Any advice, suggestions or help will be appreciated. If there are other ways to keep the batteries charged I would be glad to learn of them.

Thanks for any assistance you can offer!

[AirMiles]

I would mount a fixed 100W panel (or two, or four) to the roof and connect them using the factory prewire and Zamp rooftop box. You would also need to install a solar controller, a breaker and a switch inside the Airstream. 100W will easily keep your batteries topped off in storage. 200W will keep your batteries charged while boondocking in the sunny summer months. 400W will keep your batteries charged while boondocking in the overcast winter months.

If you do permanently mount the panel(s), I would buy at least a Victron 100/30 SmartSolar controller that can handle up to 400W of solar panels. Solar panels are addicting! Read through my "Solar Show and Tell" thread to see and learn how I did this installation with 400W on my 2017 FC25FB. http://www.airforums.com/forums/f448...ll-181608.html

My Airstream uses 120 watts per day in storage to keep the batteries full. A panel will typically provide three times its rated wattage per day. Therefore, a 40W portable panel would likely provide the 120W per day to keep your battery charged in storage. I would suggest at least a 50W portable, or better yet 100W portable, if all you want to do is keep your battery charged while in storage.

[TexAirS]

Get a 10 watt solar panel for around $20. Should be enough to maintain the battery without breaking the bank.

Works on my boat.

John

[ROBERT CROSS]

While deciding on which recommendation to follow about how to spend your money...just disconnect them.🤔
With no draw they will stay charged for a good long time.

Bob
🇺🇸

[JCWDCW]

I used to have a 75 watt portable with a charge controller that easily kept the batteries at full charge. I would think anything from 10 wats up will do what you want. Be sure to get a charge controller with the portable panel
JCW

[jnm30327]

Like Robert Cross said, just put in a $10 kill switch and stop worrying.

https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

[turk123]

Originally Posted by ROBERT CROSS

While deciding on which recommendation to follow about how to spend your money...just disconnect them.🤔
With no draw they will stay charged for a good long time.

Bob
🇺🇸

And to prove it, I had a set of interstates from my previous Airstream sitting on my bench in my barn all winter. Charged them up in the Summer and left them for dead all Fall and winter about 8 months. Remembered them a couple of days ago and hooked the charger to them to see if I killed them. 12.7 volts and the charger ran for about 5 minutes and said full.

[pjmarkham]

The original reason was because I was having trouble keeping my batteries charged while the Airstream was in storage. I have since learned I had three bad cells in one of my batteries that was less than a year old. Interstate replaced both my batteries at no charge to me. Thanks to Interstate and right now I am a fan! Therefore I will be trying storage again with the batteries disconnected and see how long they last. The Interstate rep said they should easily last 5-7 months and possibly up to a year. If that is the case I will be fine because of course I use the Airstream much more frequently that that. To all who responded thanks for your information and advice. It was all helpful as I may also add solar when time and money allow.

[hoagy_007]

I used a 15W solar charger and didn't work for me. I'd go with the kill switch which is what I did. Then maybe use the generator to top off every few months.

[pjmarkham]

Thanks everyone! I got new batteries under warranty and the next step for me is to install a kill switch.

[CD Goodman]

My 27 FC has a solar connector next to battery or I have been thinking about a portable solar panel for boondocking all this info is confusing to a 70 year old [emoji79]trying to figure this out is it just plug in or am I dreaming

[ROBERT CROSS]

No you are not dreaming...I started with 1 Zamp 120w Suitcase last year. Added a 180w this season.
I charge thru 7-pin umbilical.
The only thing you need to 'plug & play' with the suitcase is a reverse polarity adaptor on the SAE plug for the panel.

Bob...70+
🇺🇸

[CD Goodman]

Originally Posted by ROBERT CROSS

No you are not dreaming...I started with 1 Zamp 120w Suitcase last year. Added a 180w this season.

I charge thru 7-pin umbilical.

The only thing you need to 'plug & play' with the suitcase is a reverse polarity adaptor on the SAE plug for the panel.



Bob...70+

[emoji631]

🤣what is a reverse polarity adaptor? What is a SAE adaptor? And last what is a suitcase?
Forgive lack of knowledge please

[CD Goodman]

What is this thing people talked about that told the solar panel when to charge the battery and when not to?

[kenfconnor]

Originally Posted by CD Goodman

What is this thing people talked about that told the solar panel when to charge the battery and when not to?

Unless you are handy and interested in doing some research you probably should find someone in your area to do the install. For solar you need 3 primary items:
1) solar panels, either portable or roof mount
2) solar controller. Connects the panels to the controller and controller to the battery (s)
3) wiring for the above

The controller regulates the voltage coming off the solar cells.

[CD Goodman]

Thank you I am just learning about this
I have been online and am beginning to catch on "I think " zamp seem very good but I am still researching or rather wife is [emoji18] a lot to learn taking it slow.

[CD Goodman]

I had no knowledge at all before I started this been dragging a generator with me [emoji17]

[ROBERT CROSS]

Originally Posted by CD Goodman

🤣what is a reverse polarity adaptor? What is a SAE adaptor? And last what is a suitcase?
Forgive lack of knowledge please

SAE Polarity adaptor for the Zamp portable panels. It goes on the supply line from the panel to the Airstream.

You can see it on the end of my 7-pin adaptor.

Originally Posted by CD Goodman

What is this thing people talked about that told the solar panel when to charge the battery and when not to?

For the Zamp Suitcase the "Controller" is what you see mounted on the frame behind the panel.



Suitcase...


FWIW...I still take the Honda.😂

Bob
🇺🇸

[Garfish]

Trying to connect Renogy portable to 7 pin so bought a Go Power 7 pin adapter from Airstream store. But connector is Anderson and mine is MC4. So, next I got a Anderson to MC4 adapter but the Anderson was tiny compared to 7 pin Anderson female

Do you make your own 7 pin to SAE plug?

[CD Goodman]

Bought damp plug and play just have to change battery type all seems well thanks