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Anyone out there experienced with solar panels??

I am just learning the basics here I guess.

Heres the question:

I purchased used a panel about 12 x 18 inches with 2 leads coming out with batt. clips on the ends of the red / black leads.

When setting the panel in direct sunlite I connected my digital ohm meter to it on DC Volts and its showing me between 22.+ and 23.+ volts reading.

Now I was told this panel was connected to a battery on a travel trailer to help charge it.

I'm ignorant about this so can I just clip the batt. leads onto my trailer batt. and everything is beautiful.

Or do I need some kind of box to regulate the voltage coming from the panel to the batt. BECAUSE ITS SHOWING 22 + VOLTS ???

When I switched the meter to DC Amps it barely fluctuated between 1 and 2 amps mostly read 1 barely not steady.

I am also wanting to use this panel for keeping an auxillary 12 volt batt. charged that I connect my detector batts to, to keep them charged in the field.

Anybody up on this solar stuff ???? That can keep me from frying or blowing anything up !!!!!

The panel has no stickers/labels etc. giving me any info about it. And I bought it at a yard sale from a woman that wasn't very knowledgable with it.

Thanks

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Frank , yOu need a charge controller to regulate the charging voltage your battery "sees". COntrollers are sized by total wattage handled, mainly, ( and amperage). I'm figuring you'll get 30 watts max out of your panels.( Volt xAmps =Watts)......

By the way, solar modules( panels) are down to about a buck per watt, in bulk.

Look at the links and also google "solar charge controller" for more info

http://www.freesunpower.com/chargecontrollers.php

http://www.newegg.com/Product/Product.aspx?Item=N82E16882260064&nm_mc=KNC-GoogleKWLess&cm_mmc=KNC-GoogleKWLess-_-NA-_-NA-_-NA

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Go to harbor freight and the inverters are at a great price and last for many MANY years of abuse. tons a au 2 u 2 -John

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Hoser John, an inverter changes DC to AC. It wont do anything for a battery other than drain it of power while "inverting" the power from it...

Here's a rough layout: SOlar panel feeds the charge controller>> which feeds the battery>> feeds the inverter>>> feeds your AC powered toys.

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Frank, Sounds like you got the same one as I do!

There are devices that will shut off the solar juice when the battery is done charging. But the little panels don't charge much and a deep cycle type battery being used can handle it. I plug the little panel into the battery directly and it keeps my little camper charged up for days at a time. I have a couple of automobile "back up lights" as chandeleirs and a CD player that I keep blaring. I take the laptop and plug it in in the evenings and watch a movie sometimes too.

When I get back to the house I put it on a proper charger and it is only down about "1/4 of the way". They have the controllers for sale that go between the panel and the battery like in the links above. If'n I was using a big array of panels or using a lot of juice I would definitely get one of these controllers. I just bypass that B.S. and it has worked fine for my very low tech needs. I am just using the panels to supplement rather than try to fully charge though.

My trolling motor on the boat lasts two days with a fully charged battery. If'n I hook the panel up for both days I can get about three hours more out of it. So if you are using the juice the little panel will never create an "overcharge" problem I don't think.

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I have a 37 Watt solar panel from "Goal Zero", and they told me I didn't need a controller when I hook it to my trailer batteries, but I should use one if I hook it to my laptop. So far (to my knowledge) it hasn't hurt my batteries.

And that, my friends, is all I know about solar.....

Patrick.....

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The 22 Volts your seeing in open circuit volts. Under a Load within there rating it will be a little more then 12 VDC.

Place a one ohm resister between the pannel and your meter and it should show about right.

Don't worry about the open circuit values.

You need at minum a blocking diode between the battery and the Solar Cell if not already in the pannel.

Other wise at sun down the battery will back drain into the Cell. Bad Stuff.

If you can tell me the rating of the Solar Cell and how you want to use it, I can tell you a lot more info.

http://www.makeitsolar.com/science-fair-ideas/05-solar-battery-charger.htm

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Hi Frank. That little panel won't do much but it will help charge your battery. It is important to charge any battery correctly. Acid batteries need to be charged up to 14.8 volts to be fully charged and they should not be overcharged. That's what a good charge controller will do for you. It will also prevent the panels from sucking the juice out of your batteries at night. You want a 3 stage controller (bulk charge, absorb charge and float charge) to get the maximum performance and lifetime from batteries. Some controllers will also do an equalization charge. This is a plus. Charge controllers are rated in amps, and you need one that will handle the amount of current your panels will put out. Deeply discharging batteries will dramatically shorten their life.

If you figure out what electrical gadgets you want to use and how often, you can get enough batteries, a controller and enough panels to do the job. Inverters are getting cheaper every day. Some people use several inverters because the bigger they are the more they cost and the more juice they waste. Only turn the inverter on when you are using it.

I strongly recommend using 6 volt golf cart batteries and 120 or 130 watt panels. The golf cart batteries will outlast any other type of battery and you can usually get them at a reasonable price at Sam's Club. You need to keep the batteries filled with distilled water. Check the water levels regularly, especially when it is hot. Make sure the wires from your panels to the controller and to the batteries are heavy enough to carry the load and route them in the shortest possible route.

Some people mount their panels flat and some make adjustable brackets so they can tilt the panels in the winter. You lose a lot of sun this time of year if you can't tilt your panels.

Last but not least, many solar suppliers will sell you what they have in stock and it may not be the best. Do a lot of research and pricing before you start. Think about what you really really want and then get what you need. Do it right the 1st time.

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Homefire , I can't tell ya anything about specifics of the panel as there is no label or printed specs on the back side.

I think I'm gonna be alright as far as what everyone says here.

Thanks Dakota.

If Bedrock Bob can make it work with his RV CHandeliers I guess I can get some use out of it. Thanks Bob

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Yes, a panel that size is going to provide a Amp or two at most I would think.

It would extend your battery time with say a Motorized Puffer or a Recirculation Pump for sure.

Top off the battery a bit during down time.

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Slim,

you said: "Last but not least, many solar suppliers will sell you what they have in stock and it may not be the best. Do a lot of research and pricing before you start. Think about what you really really want and then get what you need. Do it right the 1st time."

This is amazingly, consistently true, dealers usually will try to sell you their stock even though there may be

much better panels etc available at the same relative price. This is an important aspect of "solar" buying especially

nowadays as the technology is improving at increasingly rapid rates.

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Garimpo,

your link is to the exact unit I have.

I put the panel on the top of my SUV,

hook it up direct to the ML battery with one of the supplied cables

and over the course of a day the battery charges up.

It's a pretty easy solution.

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Flak when I'm out in the jungle I keep one battery on charge and then change them out at lunch but your

system would be great if a person was a long distance from the vehicle or camped out without a charging

supply....

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especially

nowadays as the technology is improving at increasingly rapid rates.

There is a huge oversupply, curently. In bulk, costs are a little over a buck a watt for the panels, themselves.
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To answer your question, yes you can just hook it to the battery.

I use mine just like that Ol Yellers battery. SInce I run a bit then dig awhile this method allows me to just use solar to keep the battery charged.

You can daisy chain the panels. Also you can buy just the cell's and make the panels yourself. Look on flea bay.

What you should make is a panel stand that can track the sun @ the optimum angle. I made one out of an old transit tripod I had.

The panel will "clamp" to whatever the batteries voltage. Look where the leads come out of the panel, if it's a little box then it has a blocking diode to prevent a back drain.

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