Traveling Light Reflections
A Simple Way to Add Extra Solar Panels to the Existing 25A or 50A Furrion Solar Controller
Many new RVs are coming with solar panels and a solar controller already installed. These newer RVs are also coming with 12V refrigerators. The problem is that in most cases, these solar panels are not able to keep up with the power demand of the 12V refrigerator and all of the other 12V power components. There are a number of ways to solve this problem. However, today I am going to focus on an inexpensive way to connect extra solar panels to a 50A Furrion Solar Controller, that is factory installed and connected to either a Furrion 165W or Furrion 180W panel.
Below is an abridged version of the following table. This contains my recommendation for adding portable solar panels to the Furrion 165W or 180W panels.
Below is my original table showing all of the panels I found that may work. This also contains my recommendations for adding portable solar panels to the Furrion 165W or 180W panels.
The table above is broken into sections, Orange is for matching the Furrion 165W panel and Green is for the 180W panel. I may add other stock panels later, as manufactures slowly begin to use larger and larger panels.
The method I am going to describe is simple, it requires no special tools and will allow you to use portable panels that do not need to be installed permanently on your roof. If you decide you want to take this one step further and install permanent panels, you will need MC4 solar wire connectors and a special MC4 connector crimper.
The advantage of having portable panels is that you can set them up anywhere, avoid shade and angle them to face the sun. Some panels come with long wires, some do not. This article is written with a method that will allow you plug-in your extra panels and move them around your campsite. You will use a long solar extension cable to move the panels to the best spot around the RV.
I have collected data from different solar panel companies that sell on Amazon. I have listed the specifications from each. I have also included, in the 1st column, a calculation that compares how different each panel is compared to the original stock panel. So why bother to do this, why not just buy a duplicate Furrion panel? Great question! Well, Furrion prices are beyond ridiculous! For example, the Furrion 100W Portable Kickstand Solar Panel sells for $619!!!!! The discontinued 165W sold for over $700. Renogy has the same quality for ~â…™ the price! Also, Furrion uses proprietary solar connectors on their 165W.
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For the purpose of this article, I am going to keep it simple and focus on the information in the red box. What is most important to you is, how well it will work, the availability, size of the panel, and the cost. Everything in that red boxed section of the table should be self explanatory except for the 1st column. This column represents how different the panel is compared to the original 165W or 180W panel. The lower the value for % difference, the better the panel will work in a Parallel System with the Stock Panel. You may immediately notice that the 165W Furrion panel has less panel options compared to the 180W panel. You may also notice that my table mostly has portable or flexible panels. These are easier to move and store than rigid panels. At one point we had 8 flexible 100W panels stored safely behind the couch in our 226RK. Those are now mounted on my roof.
So now I need to get into some technical stuff but I will keep it simple. When panels are set up in parallel, the Voltages need to match as closely as possible. Panels in parallel all have their own wires running to the controller. A better way of explaining this is, for panels in parallel, all the negative wires are connected together and all of the positive wires are connected together. If a negative is connected to a positive, that would be a series string. Some systems have both parallel and series. The one we are doing here is only parallel!
For panels connected in parallel, only the voltages need to match. The currents can be different. In fact, thIn this case, all individual panel’s currents add up. For example, a 100W panel may be 20V and 5A (20V X 5 A = 100W) If you put 2 of these in parallel you would have 20V X (5A + 5A) = 200W. The panels current is 10A. 3 would be 20V X 15A=300W
The key to arranging panels is not to exceed 4 things. 1: Wire size ( not a worry for what we are doing today), 2: Controller Wattage, 3: Controller Voltage Input and 4: Controller Current Output.
The Furrion 50A MPPT solar controller can handle 600W, 135V input and 50A output. Being as this article is about using the Furrion with the stock panel, we are limited to the Voltage of the stock panel. For this simple panel add on, we need to connect the panels in parallel. If we wanted to do a series setup, we would need a new controller or need to make more complex changes than I want to explain in a “simple” article.
This diagram shows what we will be doing:
Step 1-2) Take a single solar wire extension and cut it in half. Optionally, use 2 solar extension wires and cut the MALE connector off the RED and the FEMALE connector off the BLACK.
Step 3) Mark the FEMALE RED if it is not already, Mark the MALE BLACK if it is not already.
Step 4A-4B) Strip the RED wire you just cut and twist connect it to the STOCK RED solar wire that originally went to the Furrion solar controller. Repeat with the BLACK wire you cut and the STOCK BLACK solar. I recommend that you strip more wire from all of the wires than you will be able to put back into the controller. This makes it easier to make a good twist connection. Then you can cut this, well twisted, splice to the length that will fit into the controller.
Step 5) Double check to make sure that the positive wire is FEMALE and the negative is MALE. This will make it so that when you connect your panel, the polarity is correct. Insert the spliced, combined, twisted wires into the solar controller in the correct positions. Tighten well. Test pull each wire to ensure they are all secure. That is it!!!
Additional options: You can drill through the wall between the passthrough and the front hatch. This way you can have easy access to the MC4 connectors and run the panel wires through one of the holes in the passthrough floor.
You can also run 2, 3 or even 4 panels in parallel using a splitter. They sell splitters for up to 4 panels.
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You can run multiple panels in parallel as long as the sum of the Short Circuit Currents (Isc) does not exceed 30A, or the rating of your controller! This is assuming you are using standard 10 awg size solar wire. See the table above for this information
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Panel Links
Highest recommendation LiTime 100W suitcase
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Other possibilities See Data table
Furrion 180
