What is needed to step down electrical to usb devices.

[RayO]

I want to buy Sunforce Watt Solar Trickle Charger that are normally used for charging an automobile 12v battery.

But I also want to charge devices with usb connections. What addons would be needed say for charging a smart phone so that it does not
damage it?

[Sunking]

A $5 converter you buy at any Geek Store, Geek section at Wally world, or your local convenience store setting by the cash register. Racks are full of them you use to charge gizmos in your car. There thousands of them. I take it you do not get out much.

[Logan005]

consider this, http://www.ebay.com/itm/NEW-Car-Led-...4AAOxy63FSwdKW

[RayO]

Oh yeah, I ask the guy behind the counter at my convenience store and ask if he has a MC4 male/female adaptor into a USB. And if he does not know,I will go to
Wally world and ask one of their workers.

But I won't ask you. Sunking. So don't assume that my posts here are directed to you.

BTW what are you doing with that hose in your profile picture. Looks kinda weird.

RayO

[Sunking]

Oh yeah, I ask the guy behind the counter at my convenience store and ask if he has a MC4 male/female adaptor into a USB. And if he does not know,I will go to
Wally world and ask one of their workers.

But I won't ask you. Sunking. So don't assume that my posts here are directed to you.

BTW what are you doing with that hose in your profile picture. Looks kinda weird.

RayO

There are hundreds of 12 volt to 5 volt USB devices out there. All you have to do is look and quit being lazy. You must not get out much or watch many movies. I guess you are to busy texting and surfing. Go to a Movie sometime and leave the cell phone at home. Watch Caddyshack and you will know what the hose is my friend.

carl.jpg

[Mike90250]

It's going to be a bit complicated. The 12V panel produces between 22 and 10 volts, depending on the sun, and how much load it sees, So a simple 12V - usb adapter might get fried. You need a 12V battery, even something small like a tractor or ATV battery, would work. To keep from overcharging the battery, you need a Charge Controller. Cheap ones can still damage a battery, so it's your call. And some fuses in the proper locations. Then you can charge lots of USB stuff when the sun is shining on the panels. And just 1 thing after the sun is gone.

[bigdata]

Hello sunking, I am new in this forum and have read most of your comments on solar system. I see you are an expert in the trade. I would like to ask if you can train me on solar system design, tools and installation. I am based in Nigeria. My country is faced with epileptic power problem and the way to go is to embrace renewable energy. I am awaiting your kind response.

[Logan005]

The persons with the most knowledge here are not the most patient, either deal with their social inability or rely on the nice persons with less knowledge.

[J.P.M.]

Why are there so many solar snobs on this forum. Ask for help as a newbie and get your ass chewed out ? How about ignoring a question which is too stupid for your magnificient intellect ? Maybe the hose between your legs (in your pic) is all you can think about.

I'd suggest you consider getting a thicker skin.

As for ignoring, consider that some questions, particularly when asked in a leading or rhetorical fashion can lead to dangerous or simply wasteful outcomes. Responses to such posts are often and usually for the sake of addressing dangerous thinking and the results others may take from being shown a perhaps ignorant, wasteful, just plain wrong or dangerous opinion. Keep in mind, it's not only about you, or any one poster. None of us are that important. That's why God made P.M.'s.

Try these: How about turning some of your own advice around and ignoring an answer you consider offensive, or complain to the management. There's an S.O.P. for that.

Lastly, consider that no one here has anything to gain/lose by expressing an opinion. It's not about you or me, or anyone else. It's about the sign over the door that says "Solar PanelTalk".

Take what you want of the above. Scrap the rest.

[Sunking]

Maybe the hose between your legs (in your pic) is all you can think about.

You do not get out of the house much do you? If you did, you would know what the picture is and more importantly WHO IT IS?

Rayo is trying to reinvent the wheel. There are thousands of such devices on the market already for less than $10. To build it himself takes a few years of college and a few more years of design/build experience. Even with that behind him the bits and pieces to build it himself would be 10 to 20 times more expensive than what he can buy it for already made and ready to go. He got the best advice anyone could give him.

I do not care what he thinks of me and how the message is delivered. Same goes for you.

[PNjunction]

Ok, we'll take a stab at it.

I want to buy Sunforce Watt Solar Trickle Charger that are normally used for charging an automobile 12v battery.

That's fine - just understand that charging an automobile battery with it is kind of a misnomer. These small panels are "maintainers", that is they just tend to offset self-discharge. Thing is, you need to START out with a fully charged battery for these to really work. In other words, if the battery isn't already fully charged, it will just leave the battery in the state it found it - ie, if the battery is half-charged, it tends to stay half-charged since the panel power is so weak. An inconsequential amount of charging may take place, known as a "surface charge", that makes your voltmeter happy thinking you have a fully charged battery, BUT when any sort of load is placed upon it, that dinky little surface charge blows away immediately.

EVEN with these dinky panels, there is the danger of frying your battery. That is, IF THE BATTERY is already truly truly fully charged (by a very long drive, external charger etc), and there is no charge controller inline, then you are keeping the battery well above the normal charging voltage, (even though current is very small), which fries the battery. It doesn't happen to too many people because they never truly get a fully charged battery in the first place before using it again, but it DOES happen. See here:

https://www.youtube.com/watch?v=z5RtZe9AW2E

So to do it right to cover all bases, you'll want a charge controller - even with these small panels.

So that's JUST the automotive maintenance part.

Now you want to charge devices with the panel. If you aren't going portable, then merely use a 12v > 5V usb adapter. Anker makes good ones. Thing is, you are likely to pull more from the automotive battery than the dinky little maintainer panel can put out in a day. Thus, your battery is left in a worse state than before!

Ok, so you want to be portable and attach directly to a device. Panels aren't really meant to be direct connected to anything but a battery (or charge controller), so operationally things may or may not work.

As mentioned above, you *could* try a direct connect to 12v > 5v usb adapter, but there is a good chance of frying that. These adapters are typically rated for a max input of about 16-18v, and the OCV of even a small maintainer panel can easily get up to 22v depending on manufacture. Zap!

Note for DIY'ers dealing with Sunforce products - check your polarity!! Sunforce, like many other manufacturers use SAE quick-disconnects (not mc4), and polarities here may differ so you must check. Ie, if you swap out say the Sunforce clamps with Battery-Tender clampset that also uses the SAE quick-disconnect, your polarities can be wired backwards if you don't check first!

But I also want to charge devices with usb connections. What addons would be needed say for charging a smart phone so that it does not
damage it?

The easiest way to manage this project is to divide it into two applications. For your phone charging application, just get an Anker 14W panel. It already has the 5V usb converter built-in.

For the automotive maintenance charger, get a larger one in the series, and use a charge controller.

[TommyDre]

I sometimes learn more from the sarcastic shoots and snobs than anyone else. good for a laugh too.

[PNjunction]

Actually came across something the original op may like: NOCO "Xgrid" products, and most importantly a variety of regulators (12v, 6v, 5v usb) that can be attached to either their hard 2.5 / 5w panels, or their folding panels. The regulators come in two versions, ones with the connectors for the rigid panels, and ones for the folding.

External li-ion packs, lights, all that jazz. And egads, the dinky solar panel hanging off a backpack. Laugh.

I'm actually testing a rigid 5W unit with a GC027 regulator right now (14.5v pwm inline cc) just for the heck of it for a very specific purpose not related to automotive or unattended remote use.

Unfortunately all too many don't understand the limitations, and even the damage that TOO SMALL a panel - especially if unregulated - can do to both large and small batteries under certain circumstances like permitting undercharge hard sulfation or overcharge positive plate corrosion.

Ironically, with a very very small panel, you still have to know what you are doing and why!

[compchat]

I'd suggest you consider getting a thicker skin.

As for ignoring, consider that some questions, particularly when asked in a leading or rhetorical fashion can lead to dangerous or simply wasteful outcomes. Responses to such posts are often and usually for the sake of addressing dangerous thinking and the results others may take from being shown a perhaps ignorant, wasteful, just plain wrong or dangerous opinion. Keep in mind, it's not only about you, or any one poster. None of us are that important. That's why God made P.M.'s.

Try these: How about turning some of your own advice around and ignoring an answer you consider offensive, or complain to the management. There's an S.O.P. for that.

Lastly, consider that no one here has anything to gain/lose by expressing an opinion. It's not about you or me, or anyone else. It's about the sign over the door that says "Solar PanelTalk".

Take what you want of the above. Scrap the rest.

When my daughter started playing travel softball 20 years ago and when the internet was much less mature I bought Webboard software for $3000 and created
The Fastpitch Forum. It was the buiest forum on the internet for many years and had features lightyears ahead of this crappy vBulletin. I dealt with all kinds of fathers, mostly, and coaches who felt they knew how to throw or teach a pitcher how to throw a rise ball. And believe me those arguments would get heated. Many times I had to ask them to cool it, ocasionaly to stop it and rarely lock them out. What I learned from this experience is not to allow offensive derogatory behavior to be posted. At times I had to put the forum into moderator mode so as to prevent any posting without moderator approval. Luckily most people cooperated, a few were banned and would write me emails daily demanding this or that. My point, is not to suggest people have thick skin but control your forum to make it an inviting place for newbies to ask questions of the experts. If the moderators are snobs then you will lose people who have basic legitimate questions.

BTW if you have Windows NT then Webboard is still the best software out there for conferences such as this site. You might be able to find a copy on Amazon.