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Discussion Starter #1 (Edited)
Hi
Come with me and learn a little about installing your first free standing off grid solar system.
One month ago I knew nothing about solar system and now I know what I have read but I still know
nothing about actually doing it. Within two weeks I hope to have my system up and running. I will be
posting pictures and explaining what parts are called and what they do in a easy to understand hillbilly language.

In another post I referred to an inverter as a converter. I was quickly corrected by a forum member.
And he went on to explain what each of them did in a plane and simple manner.
That's productive criticism and it is priceless and appreciated that's how we learn.

I will show every part used and tell what it does and what it is called.
this will be a somewhat smaller set up mostly for basic needs Lights and water. --maybe a radio,
tv or computer. for news (shortwave radio?)

I'm hoping that there are a few experts in here that can chime in and point out mistakes
and help all of us learn with helpful suggestions.
Don't hesitate to ask questions. Your survival may depend on what you learn here.
I will start posting here on Monday and continuing to post until it's working.

Please keep in mind when you make suggestion keep the language and explanations simple
This is first grade for me -- Not my fourth year at Yale
I hope you guys like this idea [/I]

SCROLL DOWN AND CHECK PAGE TWO FOR UPDATES
 

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I too will be waiting to see the replies. I want to go solar, but get really lost on the solar websites. Look forward to seeing what you build.
 

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I will also be following this thread. Solar is something I don't know anything about, but I want to change that! I have been thinking of building a semi-portable BOL shelter out of a shipping container and would like to use solar to charge 12V batteries for the lights. Thanks for the thread.
 

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One thing to keep in mind is solar is real power. Yes it might only be a 12 volt system but they put out up to about 20 volts. The first half of the system I put up was 2x125 watt panels. I ran the wire inside an interior wall and put in a retro fit wall box and installed a double pole double throw switch. In the up position the power was sent to a grid tie inverter. The middle position was off. The down position sent the power to the charge controller for the battery bank. After awhile I noticed the switch had gone bad. When I removed the wall cover and looked at the switch it was fried. Probably a loose connection had caused it to over heat and burned it badly. Could have started a fire. I have replaced that switch with a 120 volt 3 way light switch. I feel much better about that now. I have left it hanging out of the wall and checked it on a sunny day and it doesn't get warm at all. One other thing I would suggest is to get a kill-a-watt meter. The grid tie system plugs into it and then into the wall outlet. You can see how many watts your system is making and how many kilowatt hours are made. I used to unplug it at the end of the month to reset it to zero but I found that we never have a month were the power doesn't go out at least for a split second. Now I do it everyday at sundown and record the readings on a piece of paper. The meter cost 20-23 bucks on ebay and it will help you set the angle of your panels for the most power. I just added 2x100 watt panels and I'm now making about 2 kilowatt hours a day. So about 60 kwh a month and my average usage is 300 kwh a month. So making about 20 percent of my monthly usage and keeping my batteries topped off. I bought 2 6volt gulf cart batteries that will be wired in series for 12 volts but haven't hooked them up yet. Good luck building your system.
 

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Not all switches are rated to handle DC. Make sure the switch is rated for the maximum possible amperage the system is capable of putting out. Make sure the wire is capable of carrying the maximum possible amperage for the length of the wire. The longer the wire, the "thicker" the wire should be. As an example, in my motorhome, the wire feeding my 400 watt inverter is # 1 welding cable. It is less than 22 feet long. This prevents voltage drop, which can cause heating etc. At least once a year, check the tightness of all connections, especially if you used solid rather that stranded wire. Even in your house(120/220 VAC), you should check the tightness of the wires on your breakers or fuses.
 

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Discussion Starter #10 (Edited)
Hi Guys
Sorry about not posting but I had to go out of state. Ok back to the solar project.
The panels are mounted so tomorrow I'm going to get started on the wiring. So far I have learned that the correct wire to use is called AWG cable I'm going to use a 12 gauge stranded wire. Oh, Also I learned the smaller the number the thicker the wire. The connections used on solar panels are called "MC4" you can cut the cable to the length you need and install your own ends they're easy to find on eBay and so is the cable.
Tip- When you're installing the ends don't stick the connection end into the MC4 assembly to see if it fits until your ready to install it. It seems as though the wire ends have Barbs on them that insures that the ends won't come loose it also makes them unforgiving. They won't come back out--Trust me on this one. The MC4 adapters connectors are like a two into one wire setup. And you can use two of them if you need a three into one or use three for a four into one and so on. In the picture you can see the white wire hold downs I'm going to use (maybe) they are for house wiring but I think they will work out nicely. I found them while roaming around aimlessly at Home Depot. This is learning experience so if you see something that is incorrect please correct me.
If there is something that you would like to see a close up of let me know.

 

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Discussion Starter #11 (Edited)
Ok today I wired up the panels and the controller.
When you use the adapters to join together the panels it looks a little scary but it's not hard to do at all.
The white wire holders that are for home wiring worked great on the solar wiring it held them down tight the height was just right. The one looks loose but I left them that way until I was all done then I went back
and pulled the wire tight and finished hammering them down.


I got thinking about what hayden said about needing a meter to see what was going on so I
left some slack in a place where I am going to wire in a watt meter to show what the panels
are putting out. The meter is ordered but might take a while to get here.

 

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Discussion Starter #12 (Edited)
From what I have read there are basically two types of controllers
1-- pulse width modulator or PWM
2-- maximum power point tracking or MPPT
Everything I have read says that the MPPT will give you about 30% more charging power from the panels so
I went with the MPPT and I got a 30 amp. I guess if you get an amp that is too big it will work fine and you can add
more panels on later. But if it is too small (too low of amp rating) you might fry something. -bigger is better



As for batteries I have read that the golf cart batteries are the way to go and I was going to do
that until I priced them,,Ouch I did some checking around and I went with a Walmart dual purpose
battery It even has the amp hour rating right on the battery it's 114 hr @1a I did some checking and for
$99 each it was about as good as your going to get and comes with a 2 year full replacement warranty
they are very heavy.



Here are some hold downs that worked great I not sure but I think they are for some sort of cable
but I'm not sure. They're easy to find at a home improvement store they work great on the smaller
12 volt wire for lights and stuff. After reading haydens suggestion on switches I went with a 20 amp switch.
I will be using the switches later.



This is what the cable hold downs will do. They worked out nice.



Well I hooked up the panels to the controller and batteries and the lights on the controller
came on and says it's working. But with no gauge it's hard to tell how well.
I also ordered a remote gauge that will go on the inside the house that will give me
lots of information. It plugs directly into the controller.



This is the remote meter I will be installing when it comes in
I'm not sure how long it will take to get it.

 

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Discussion Starter #15 (Edited)
Before it's over I would like to have two battery packs with two batteries in each pack I was going to use two of these switches to switch from one pack to the other 20 amp was the heaviest I could find.

What does the switch disconnect? seems small if it's on the DC side.
 

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You need to have a switch that will handle the amp for the load or even higher. Remember that if you're switching the DC to an inverter pulling 3 amps AC, that going to be over 30 amps DC. DC switches handling 100 amp can be found at marine supply and frequently can handle to battery banks individually or can put them together in a combined bank. Check these for $30 to $40, if you need a switch to handle high load DC. I'd make sure the inverter is shut off before turning off the DC switch.
BLUE SEA SYSTEMS m-Series Mini Battery Switches at West Marine
 

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Before it's over I would like to have two battery packs with two batteries in each pack I was going to use two of these switches to switch from one pack to the other 20 amp was the heaviest I could find.
I have a question, and I ask this out of pure ignorance: why is it advantageous to have two banks of batteries with a switch between them? Why not wire the banks in parallel (without a switch) so you are charging them at the same time and drawing from them at the same time? I would think that would double your watts without having to pay attention to when one bank is full (or empty) to switch over to the other bank.
 

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Discussion Starter #18
So far everything I have is 12 volt but I have been thinking about a inverter for TV, computer and maybe some
other small items. What size inverter do you think I should get? How many watts?

It's going to be a while before I have the parts to go any further and finish this project. (about 2 weeks)
For now it's up and running I have lights running off my solar setup and I'm happy with that for now.
The basic setup is done I will be back to this thread when I get parts. Just a few add ons to tweak the system.
And I will check back to see if there is any questions

I was thinking about starting on another project until parts come in. I am going to put in a complete water system
with hot/cold running water. I think if I have independent lights and running water I'll be ahead of the curve when SHTF.
I hope to use a 6 gallon propane water heater and 12 volt water pump out of a travel camper.
 

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Discussion Starter #19
I have a question, and I ask this out of pure ignorance: why is it advantageous to have two banks of batteries with a switch between them? Why not wire the banks in parallel (without a switch) so you are charging them at the same time and drawing from them at the same time? I would think that would double your watts without having to pay attention to when one bank is full (or empty) to switch over to the other bank.
Well just sort of a reserve set up I just like the idea of having a fully charged set of batteries in reserve just in case.
These batteries are good for holding a charge while in reserve. -Just a preference- If a battery gives me a problem
I can switch over to the other set until I have time to figure out what's wrong (without being in the dark)

If you take a look at the wiring on the solar panels you can see that they are wired in so I can unhook one at a time if
I have a problem and need to replace or check one (I have two spares) hope for the best and plan for when TSHTF
everything is wired 12 volt just to keep it simple
 

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If you take a look at the wiring on the solar panels you can see that they are wired in so I can unhook one at a time if
I have a problem and need to replace or check one (I have two spares) hope for the best and plan for when TSHTF
everything is wired 12 volt just to keep it simple
I did not notice that until you pointed it out. Good thinkin'! Great thread - thanks!
 
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