Solar - Did Search And Didn't Find What I Needed

[Dan Lockwood]

Not sure if this is the correct forum to post this in. Maybe Modifications & Upgrades would be better, not sure.

The moderator can move it if needed.

I'm thinking of adding a small, 100w to 200w array of solar panel to just "maintain" my two group 24 12v batteries while in storage.

Since they're already hooked up to the inverter through the RV, I'm thinking all I need to do is to hook the output from the panel controller directly, albeit fused, to my batteries.

Is there a simple kit because all I've found are for those wanting to run off batteries and I do NOT want to do that, just "tender" my dual batteries until I'm hooked up to the truck or to shore power.

If anyone has done this in a permanent installation, where did you mount the solar panel? For my storage lot, I'm thinking I could just sit it on the ground with a couple concrete blocks on the stand to hold it in place while it's pointed south in the sky.

Any suggestions would be greatly appreciated.

[busterbrown]

Couple of thoughts:

Are you looking to maintain or recharge? A 200W solar panel seems excessive as a storage "maintainer" solution.

Anything not bolted down (or secured up on the roof) has MORE incentive to grow legs and walk away. Are you okay with that at your storage lot?

They have plug and play (built in solar controller) battery "maintainer" units that are relatively cheap and can do what you're asking. Just as an example, Battery Tender has 5, 10, and 15 watt panel kits available. This is the 15 watt kit:

https://www.amazon.com/Battery-Tende.../dp/B004Q820TQ

[Dan Lockwood]

Originally Posted by busterbrown

Couple of thoughts:

Are you looking to maintain or recharge? A 200W solar panel seems excessive as a storage "maintainer" solution.

Anything not bolted down (or secured up on the roof) has MORE incentive to grow legs and walk away. Are you okay with that at your storage lot?

They have plug and play (built in solar controller) battery "maintainer" units that are relatively cheap and can do what you're asking. Just as an example, Battery Tender has 5, 10, and 15 watt panel kits available. This is the 15 watt kit:

https://www.amazon.com/Battery-Tende.../dp/B004Q820TQ

Shows my solar ignorance. I thought that 100w or 200w was a very low output, but the less than 20w will probably do me very well.

Yes, just like my Harley's Battery Tender, once full it's used to maintain, not to charge a battery.

I'm moving to a new parking spot on the other side of the lot and I need to see which way's south. Then I can figure out what I should do. I don't think theft is going to be an issue in this lot.

I like the idea of a self-contained unit that doesn't need a controller, just a clip it and set it up in the sun.

Do solar panels absorb energy from the batteries when it's dark out? Or are there diodes in the circuit to keep them from drawing on the batteries?

Thanks for the information, I'll do some looking online now.

[Roscoe]

you will want a controller as that is what controllers the solar panels and makes sure your not over charging your batteries.. It will sense how much voltage your batteries are at and will regulate how much voltage and amps are needed to keep the batteries fully charged

[Dan Lockwood]

Russ, the Battery Tender that was linked above does have its own self-contained controller and you just clip it to your battery and set it in the sun. No "extra" components are required like just solar panels require.

At $110 for the 15w, that's not bad.

I've sent a contact info to Battery Tender to see if this unit, Battery Tender 12V, 830mA, 15W Solar Battery Charger, is sufficient for dual batteries or just one battery. Should know more tomorrow.

If this is going to do dual batteries, it's just what I'm looking for!

[flybouy]

I'd suggest securing it with a cable lock to keep honest folks honest. If you do have a
'safe" storage lot don't tell anyone. A few years ago I thought the storage lot I used was safe. They have good lighting, manager lived onsite, and 51 security cameras. A drug addict broke into 29 campers. Mine was one of them. He did over $4K in damages to mine. They ended catching the guy and locked him up for 15 years but as they say "the damage was done".

[Roscoe]

Dan,

I missed that part of the maintainer.. should do the trick for what you are wanting. If you ever go further with it then feel free to PM me. Just finished a 400watt 4 panel roof installed to 6ea 6volt golf cart batteries, charge controller along with a 1200watt pure sine inverter w/ auto transfer switch to run all the plugs and gfi plugs in the trailer.

[Dan Lockwood]

Thanks everyone for the great input!

I got a reply back from Battery Tender. He said that for the dual batteries I would need two (2) 15w systems, one for each battery.

If they're hooked up in parallel, the combined total is still 12v. They are hard wired together and I can't see that by feeding each battery individually that it would be any different than just hooking to one with a slightly higher wattage single solar panel.

Am I missing something?

Thanks and I hope you all have a great weekend...

[Canonman]

I use a battery tender when I remove my trailer batteries for storage. Also use one on the Ram since it sees little use during the off season as well. In both cases I have the batteries connected in parallel. I connect the tender to the positive of one battery and the negative of the other. Electrically this looks like one larger battery to the tender and has worked for me for over 6 years.
For the OP's solar/maintainer idea, I'd suggest disconnecting the batteries from the TT circuit either manually (pulling the positive lead) or with a battery disconnect if equipped. The portable solar panel should connect to a controller. The controller is then connected to the batteries to monitor safe charging levels.

[Roscoe]

Dan,

since that panel from amazon you were looking at has the battery tender piece with it, you can parallel your 2 12volt batteries (they should be already if you are using 2 in the camper) and go to the positive on one battery to the negative on the other with that setup and it should charge them both at the same time

https://www.youtube.com/watch?v=bfvLcTxgvzo

[German Shepherd Guy]

Ho Dan. The Battery Tender people probably already answered your question but just in case, You are right there are diodes in the system so that you do not have to worry about the panels discharging your batteries during the dark hours.
Oak

[Dan Lockwood]

All great information, thanks.

I'm learning more each day I read on this forum, thanks again!

[travelin texans]

The last couple winters I had my 5er stored in Arizona I had a small 3-5 watt solar panel tied to the hitch with the + hooked to my one battery & the - to the other, with batteries disconnected from the RV fully charged that little panel maintained the batteries to 12.3 volts all winter. The panel at Batteries+ Bulbs was $35+/-, well worth it.

[Dan Lockwood]

I ordered a 35w Newpowa solar panel kit.

The controller is capable of up to 10A charging and also has a maintain function.

I plan on mounting it up front off the pin box. There's two 1/2" holes just under 8" wide and I'll use a blind nut rubber nut sert type mounting bolts to hole it in place. I plan on mounting the controller inside the battery compartment. I'm not sure quite yet what I'm going to do for the interface from outside wiring to inside wiring, but had thought originally of mounting a cigarette lighter socket on the front and using a plastic plug to seal it up when not in use. Then on the solar panel wiring I would just have a cigarette adapter on the wires. I would use the stick on wiring harness plastic wiring twisties and just clip the wire up when in use and unclip it when taken down.

I'll only use it when I'm in storage and probably keep it home in the garage someplace. My new storage space is like a cul de sac space in that it's 12' wide up front, but opens up to around 30' in the rear. I've already had all three slides out and did my auto level first though. My last space was 12' all the way in and when I open my doors I had about 4" of clearance, very tight.

Thanks everyone for the information and help with this.

Oh, the kit was a few cents less than $62 with free shipping and no tax... 10 year 80% output rating and 20 year 60% output rating. 2 year full parts/labor warranty. They were very helpful and replied very quickly.

I'll post pictures of it mounted in a few weeks.

Thanks and have a great day!

[B-O-B'03]

I bought some Anderson connectors and added one to my batteries and use it to plug my solar panel, macerator pump, compressor and any other 12 volt items in to.



It works great.

I did not mount the solar panel, I bought a tilting mount for it and just put it on the ground, where it will get the most sun.

[Dan Lockwood]

Okay, I've added my 35w solar panel and controller to my Raptor. I have dual 12v batteries in parallel of course.

I finally found a 12v bulkhead plug with a water tight cap. Here's my somewhat crude install. Still can be updated on the wiring if needed.

The only reason I want the solar panel is to keep up my batteries while at the storage lot, not for any boon docking etc.

My Raptor sits facing directly south in my storage lot.



I have three heavy duty magnets on a stainless bracket on an aluminium solar panel frame, so not rusting etc. It just snaps to the top side of my pin box.



The wiring runs along the underside of the nose and is held in place by stick-on twisties and can be undone quickly.



The 12v wiring just plug into the bulkhead plug over the battery box.







I mounted the controller onto the wall between the batteries and the generator.





This is the plug harness I purchased.





I'll let you all know how well it works in a few weeks.

Any suggestions?

Thanks and have a great evening!

[Cire8002]

Originally Posted by Dan Lockwood

Not sure if this is the correct forum to post this in. Maybe Modifications & Upgrades would be better, not sure.

The moderator can move it if needed.

I'm thinking of adding a small, 100w to 200w array of solar panel to just "maintain" my two group 24 12v batteries while in storage.

Since they're already hooked up to the inverter through the RV, I'm thinking all I need to do is to hook the output from the panel controller directly, albeit fused, to my batteries.

Is there a simple kit because all I've found are for those wanting to run off batteries and I do NOT want to do that, just "tender" my dual batteries until I'm hooked up to the truck or to shore power.


If anyone has done this in a permanent installation, where did you mount the solar panel? For my storage lot, I'm thinking I could just sit it on the ground with a couple concrete blocks on the stand to hold it in place while it's pointed south in the sky.

Any suggestions would be greatly appreciated.

Simple and cheap 12v solar battery charger gives you a steady trickle charge from Harbor Freight $15.
https://www.harborfreight.com/15-wat...ger-62449.html

[flybouy]

Originally Posted by Cire8002

Simple and cheap 12v solar battery charger gives you a steady trickle charge from Harbor Freight $15.
https://www.harborfreight.com/15-wat...ger-62449.html

!5 watt solar charger has the "potential " to supply about 1/10 Amp. That's near the equator, high sun, no clouds. That would never charge, nor maintain a car battery in real life. Maybe a cell phone.

[JRTJH]

Originally Posted by Cire8002

Simple and cheap 12v solar battery charger gives you a steady trickle charge from Harbor Freight $15.
https://www.harborfreight.com/15-wat...ger-62449.html

Originally Posted by flybouy

!5 watt solar charger has the "potential " to supply about 1/10 Amp. That's near the equator, high sun, no clouds. That would never charge, nor maintain a car battery in real life. Maybe a cell phone.

Add clouds, trees, smog, the angle of the sun and the total hours of exposure in North America and 15 watts may not even maintain a cell phone charge.....

Now, if you've got a "dim solar patio light"..... Maybe, but buy two and figure out how to connect them, even for that 1.5 volt AA battery powered patio light from the Dollar Tree.....