RV Solar How Much Do I Need and How to Wire Them
This is what I installed the solar system on. It's a 2005 Custom GMC Super C.
Please see How to Install RV Solar Panels for Installation Instructions
These are the panels. They are 175 watts each. I'm installing 4 for 700 watts.
I'll be attached them directly to the roof.
I need 700 watts because I'm running an electric fridge, a swamp cooler, lap top and lights.
I will use 4-6 volt batteries, a 2000 watt inverter and a 40 amp charge controller.
Someone figured that 6 volt batteries will hold a charge longer than 12 volt. We recommend 6 volt.
Why 4 batteries. Think of your battery reserve like a pond. 2 batteries would be like a small pond.
12 batteries would be like a lake. 4 has worked great for me.
Once you have your panels installed you need to connect them to a RV Solar Charger.
This will control how much wattage is fed to your batteries so you don't burn them out.
The output of my panels comes straight into the charger. The output of the charger connects to the batteries.
The best way to do this is just connect these outputs to the connections in your converter where the batteries
come into it. I'm using this 40 amp MPPT charge controller because the output amperage of each panel is 9 amps.
I should have a total of 36 amps. However, I have never seen more than 9 amps come out of the entire panel array.
This is a great charger because you can set the charge voltage where
you want. I set mine at 14.3 volts. Most inverters will shut off at 11 volts. This gives my 5.3 volts to use before shut down.
I've never gone below 12.3 volts.
I'm not going to give you a lot of calculations and specs here.
I've arrived at this set up from trial and error which is really a lot better way.
I'm have a 2000 watt inverter. I sometimes use a lot of power. The electric fridge stops and starts all day.
When it starts up there is a spike or peak that can be 1000 watts or more for a 100 watt fridge. So, if I'm using a lot of
power these spikes can cause the inverter to overload and shut down. Which means my 2000 watt inverter with 4000 watt peak
might not be what is advertised. But, it works pretty good for what I have and for the price. If you don't need that much
power, you want to go with a smaller inverter as it WILL use power just when it's idling.
You'll see that I have the inverter mounted very close to the batteries. This is very important.
Long cable runs will use a lot of power. All your cables for batteries and connection to the inverter should be
at least 4.0 gauge or 4 agw.
The output of the inverter can be 12 gauge romex.
This is my remote for the inverter. Works great and it has a simple voltage meter on it.
You'll also see my generator remote, my Input Power Switch and a switch to turn the converters charger on or off.
The Input Power Switch allows you to choose between: Shore, Generator or Inverter power.
You need a switch like this because: if
you're connected to shore power, you aren't feeding power to the outputs of the generator and the inverter.
This will burn them out. The Input Power Switch isolates each source. Many factory RV's will have electronic switching
which I gues you could get but I prefer a 'simple' switch. The switch has 3 inputs and 1 output. You'll connect Gen, Inverter and Shore to the inputs
then connect the output to the 12 volt connections on your converter.
The charger switch is required when you connect the inverter output to to converter. When you're running off
batteries and you try to also charge the batteries you create an internal loop that will shut the inverter down.
So you need to have a switch that turns the charger off. In your converter you'll find one wire that powers
the charger. Put the switch on this wire.
Buy these solar panels Here
Buy the Edecoa Inverter Here
Buy the Solar Charger Here
Buy the Input Power Switch Here