Shopping Cart
0 items

RV Solar System Components

Food for Thought Part 2
Selecting Components for your RV's Solar System

In this article we are going to skip the science and technology behind these components and offer food for thought from an alternative perspective.

There are a lot of choices when it comes to selecting the components you'll need for your RV Solar System. Some components are inexpensive and some cost an arm and a leg. Solar for RV's is one of those things that you get what you pay for!

If low end components are chosen you'll get a system that will charge your battery but maximum performance will never be achieved and it's quite possilbe that one of the components will fail prematurely. Here's something to think about. What if an inexpensive off brand charge controller happens to fail (stuck open) while the RV is in winter storage? The controller will over charge the batteries, boil them dry and possibly cause a fire! How much did you pay for that RV?

Being RV Solar System installers we've replaced a few charge controllers that failed which were included with some of the inexpensive kits. Whether you order from RV Solar Store or any other site... please buy quality components for your RV solar system!

RV Solar System Components

The scope of this article is to give the do-it-yourself installer a basic overview of some of the quality RV Solar System components that we frequently use in our own RV installations and offer for sale on this site. We'll start on the roof and work our way down.

RV Solar Panels

Today their are several high quality solar panels on the market. Sharp, Mitsubishi and Kyocera are three of the best known brand name module manufacturers that are currently being used on RV. We installed Mitsubishi in the past and migrated over to Kyocera 130's then to the Kyocera SX-UPU 135. All three of these solar panels are built rock solid and will produce maximum power longer than you will own your RV.

The other option is to buy a Chinese solar panel. Some of these modules are good some are not! They all offer fantastic warranties and don't care where the module is installed. I wonder why this is? Probably because trying to get warranty coverage from an offshore company will be impossible.

I bought a cheap 20 watt Chinese solar panel 5 years ago for my boat. The glass like coating on the top of the module that protects the solar cells from the element is starting to crack! I'm guessing within the next few years this module will head to the junk pile. That's OK on this little 20 watt module, but I'd be unhappy if this was a larger 100 watt plus solar panel.

RV Solar Panel Mounts

Until recently there were basically only two mounting options available for fastening the solar panels to the roof of the RV. Flat mounts or tilting mounts. We'll discuss each type of solar panel mount below.

  • Basic Flat Mounts - Flat Z Mount RV Solar Panel Mounts is a  "Z" shaped piece of aluminum. Fixed flat "Z" mounts are the lowest cost option for mounting your solar panels. These mounts are a good choice if you are installing a small solar system or the RV does not have a ladder for accessing the roof.
  • Smart Feet Solar Panel Mounts - We have recently introduced our "Smart Feet RV Solar Panel Mounts". These mounts take the basic Z mount a step farther. They are a two-piece Z mount that compensates for roof curvature with 1" of vertical adjustment and a pivoting upper mount. "Smart Feet Solar Panel Mounts" are a great choice if your RV roof has a bit of curvature to it. Smart Feet allow you to easily remove the solar panel for rubber roof maintenance. "Smart Feet" can be installed with one set of mounts set at the highest position and the other set at the lowest position which tilts the solar panel a couple of degrees making modules somewaht  "self-cleaning".
  • Tilting Solar Panel Mounts - We have developed what we feel is the best tilting solar panel mount on the market. The patent pending RVSC Dual Tilt Solar Panel Mount has the ability to easily and quickly tilt your solar module in two different directions. Tilting your solar panels towards the sun dramatically increases solar current output.  These mounts are a must have for full timers or those who camp during the winter months.

Solar Wire

For RV there's no such thing as solar system wire. All wire is an adaptation from other applications. You've read on the net about folks wiring their solar panels with 8 or 6 gauge wire. There's two problems here. One is that AWG wire is not rated for use under solar modules. Problem two is if the modules came with MC cables, that wire is 10 gauge at best, or if the solar panel has a junction box the connections in the junction box were engineered for 10 gauge wire. It is difficult to make a good solid connection in the junction box with large heavy wire.

There are two types of THHN 10/2 tray cables available that are rated for the temperature extremes that are common under solar panels. One of these tray cables is gray and has a round outter shell. The other is black and has a flat outer shell. Either cable works equally well for passing current from the solar panels to the charge controller or combiner box.

We prefer the black flat 10/2 tray cable for two reasons. This tray cable is more flexible and passes thru the cable slots in our large dual tilt solar panel mounts. Once inside the RV (out of the weather) a transition can be made to a heavier gauge wire heading to the charge controller and then to the battery bank.

RV Installation Kits are available for single panel and multiple module installations.

Any DC type stranded wire can be used from the charge controller to the battery bank. We usually use a fine strand 8 guage wire and if the customer wants to spring for larger wire we have 6 guage fine strand welding cable that we can use. Again there are connection issues with large gauge wire. Terminal blocks on most charge controllers were built for 10 gauge wire. We can squeeze 8 guage in most of the terminal blocks but 6 gauge is nearly impossible without nipping off strands.

RV Solar System Charge Controllers

Don't skimp on your solar charge controller. The charge controller is the heart of the RV Solar System. Charge controllers are not created equal! A cheap controller could possilbly burn your 50K RV to the ground! A good MPPT charge controller will actually increase your RV solar systems current output. That's like getting a free solar panel!

Blue Sky Solar Boost 2000EA while back I had a retired full-timer call looking to replace his charge controller that had died. He had a couple hundred watts of solar so I recommended the 2000E MPPT. He about went thru the roof when he found out the controller was pushing $300.00. He said he could buy a controller for $80.00. This fellow either just didn't see the light or wasn't in a position to be able buy an MPPT controller.

Charge controllers manufactured by Blue Sky Energy, Morningstar and Xantrex are safe bets. We prefer to use Blue Sky Energy controllers in our installtions. For 1 or 2 solar panel installations the Blue Sky Solar Boost 2000E 25 Amp MPPT controller is our preference. This flush mount controller has a digital display that shows battery voltage, module output current and boost current.

For larger systems the Blue Sky Solar Boost 3024iL MPPT 40 amp with IPN remote or the Blue Sky Solar Boost 50 amp is an excellent choice. All Blue Sky charge controllers are assembled in the USA.

For reliable high quality low cost charge controllers Morningstar Corporation has the SunSaver 10 Amp PWM Solar Controller. We've installed a few of these single module controllers for customers who didn't care about system information. To date none have failed. Morningstar also manufactures a SunSaver 20 Amp PWM Solar Controller that can regulate a couple of large solar panels.

Morningstar has two higher priced products with a digital display the SunSaver Duo 25 Amp 2 Battery Bank Solar Charge Controller and the Tristar 45 Amp MPPT Controller.

A fuse rated for the solar controller needs to be installed at the positive battery connection.

Continue to part 3 Putting all the parts together... Installing the RV Solar System