DIY Solar Power - Made Easy!
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  • DIY Solar Packages
    • EG4 Off-grid System Builder
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    • Mobile Systems >
      • 48V 3kW Handtruck System
      • The Minimalist (great for small vans and cars)
      • The Classic 400 Watt (RV's, Vans, Buses)
      • 400 Watt w/ Alternator Charging
      • The Off Grid King (Power Anything!)
  • Solar Batteries
    • 48V Server Rack LiFePO4
    • 48V Vertical Mount LiFePO4
    • 12V Lithium Batteries
    • Battery Capacity Testers
  • Solar Components
    • 50-250W Solar Panels
    • 300W+ Solar Panels
    • Ground Mount Solar Racking
    • Inverters
    • Solar Charge Controllers
    • Battery Chargers
    • Wire and Connectors
    • Fuses and Circuit Breakers
    • Tools
    • Battery Monitors
    • Automatic Transfer Switches
    • Battery Isolators
    • Raw LiFePO4 Cells
    • BMS
    • Solar Friendly Air Conditioners
    • 12v Fridges
  • Free Solar eBook
  • Plug-N-Play Systems
    • Full Size Systems
    • Ultra Portable Systems
  • Videos
    • Solar Power for Beginners
  • The Forum
  • How to Mount Solar Panels to a Vehicle
  • Contact Me
  • Policies and Disclaimers

The Classic 400 Watt Solar Package
​Ideal for RV's/ Vans/ Buses

This setup works well if you:
  • Spend a lot of time inside your vehicle, moving or stationary
  • Plan to use a large van or RV
  • Plan to run most appliances, such as a computer, microwave, fridge and more
Recommended components:
  • 400 watts of solar panels and a 40 amp MPPT charge controller
  • 300 amp hour lead acid deep cycle battery bank (or 200 amp hour lithium battery)
  • 1100-2000 watt inverter
Estimated Cost of Components:
  • ​$500-$600 for Solar Panels
  • $200 for Solar Charge Controller
  • $430 for Lithium Batteries
  • $200-$300 for Inverter
  • $160 for Branch Connectors/Cable Entry Gland/Wire/Crimp Connectors/Fuses
  • $50-$150 for Tools (Cheap tools are available, but you are better off buying high quality tools)
Estimated Total Cost:
  • Complete System with Lithium Batteries: $1,590!
The Classic 400 watt is my favorite size, most people will love this setup!

400 watt Solar System Blueprint

Warning: Please read my book for full installation instructions and safety considerations!! 
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Step 1: Mount components to a wooden board like this:
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This picture should give you a rough idea of how to mount and connect your components. Each system is different though, so be sure to use my book to calculate the fuse and wire gauge size for your components. This picture does not cover other remote wires/shunts/temperature compensation wires etc, so please be sure to use my book to understand how this all works!

Step 2: Connect the Battery Bank
If everything is installed correctly, the solar charge controller should now turn on, and you should be able to run the inverter. You may see a small spark when you connect the inverter to a battery, and this is completely normal.
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Step 3: Mount Solar Panels to the roof and Connect them to Solar Charge Controller

If you follow the previous steps correctly, the solar charge controller should now be charging your battery! (if there is sunshine present)
​For more information on how to do this, please check out my book :)

What Components I recommend for this system:

​(I make a commission for purchases made through the links below)

Buy 400 watts of glass solar panels and a 40A MPPT:

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Doesn't get cheaper or easier than this! This kit is everything you need to charge a 12V battery with solar. 
  • 4X 100W Monocrystalline Panels
  • 1X 40A Lithium Specific MPPT w/ Bluetooth Communication
  • Solar panel extension wires w/ MC-4 and inline fuses
  • 4X Z-brackets for mounting your solar panels
  • Large fuse for the MPPT

Buy direct from rich solar by clicking here

​Or for $200 more, you can get the same kit on amazon by clicking here (not recommended, but people prefer amazon)

Purchase This Battery:

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​Buy 1 or more of these:
The Li Time 12V 240Ah Plus Battery. Best bang for the buck lithium battery around!
  • Low Temperature Protection. Every other battery at this price point does not have low temperature cut off. This one does!
  • This battery will last 3,000 to 5,000+ cycles
  • It is small and light weight. 
​
230Ah Li Time Battery Click Here to Purchase

​If you need a cheaper battery, ​click here for more options

Choose an inverter:

Modified Sine Wave Inverter 

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2000 watt modified sine wave inverter
(modified sine wave will power 95% of AC appliances. they also cause appliances to have a small humming noise. Induction loads (such as microwaves and motors) run with an added 30% loss in efficiency.

​A lot of people still use these inverters, but most people would prefer a pure sine wave inverter.

​
Click Here to Purchase

Pure Sine Wave Inverter
​(recommended)

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 2200 watt pure sine wave inverter
(pure sine wave inverters are better and more efficient, and work with all AC electronics)

Pure sine wave is the way to go. They cost more initially but work much better!

Click Here to Purchase


The inverters above are considered "budget friendly". If you wish to buy a top of the line inverter (UL listed with remote operation and data logging etc) Click here

Wire and Adapters:

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High-Quality Copper Wire for DC appliance hookup
(most wire on amazon is "copper clad aluminum", which is cheaper but lower in quality):

50 feet 10 gauge Blue/Black
Click Here


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​Battery to Battery Cables

Any size battery (be sure to select the right size for your battery bank) Click Here
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​Pre-fabricated Battery to
​Inverter Cables
​(if your inverter does not come with them)

make sure that the holes on the connector will work with your battery/inverter

12 volt 500-1100 watt inverter
Click Here


12 volt 1000-2000 watt inverter Click Here



12 volt 2000-4000 watt inverter Click Here

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Main Component Hook-up wire/connectors/heatshrink
Requires a Hammer-type Crimper and Assembly. Great for custom built systems where length of each wire matters. If you are a beginner, stick to pre-fabricated cables.

Click on a link below and choose your wire gauge
​(default length is 10 feet of red, 10 feet of black): 
  • 8 gauge kit
  • 6 gauge kit
  • 4 gauge kit
  • 2 gauge kit
  • 1/0 gauge kit
  • 2/0 gauge kit
  • 4/0 gauge kit

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Branch Connector 
Wiring multiple panels together requires a branch connector. Connect all of your panels together on the roof and combine them into two wires which will connect to the solar panel extension cable (Solar panel to charge controller cable above)

2 wire mc-4 branch connector
​(1x pair required for 400 watt system)
 Click Here

Solar Panel Cable Entry Gland

When your solar panel array wires enter your vehicle, you will need to drill two holes. Use this cover to prevent roof leaks from developing.

 This system requires x1 Click Here
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Required fuses, fuse blocks, bus bars and circuit breakers:

​Battery Bank To Inverter/Fuse Block Main Fuse

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MegaFuses work great and cost very little money, and are preferred over the typical ANL fuse you would find from most solar distributors. Unlike ANL, Megafuses can be used with 24V/48V systems and have a higher disconnect amperage. Stick to these fuses if you do not want to have problems with your 12V system.

How to size an MegaFuse for 12V inverters (or any appliance really): 
  1. Take the continous wattage rating on the inverter and divide it by the voltage it operates at (12V)
  2. Let's say you have a 1500W 12V inverter. The maximum amperage it requires is 1500(W)/ 12(V) = 125 (Amps)
  3. Take the maximum current (125Amps in this situation) and multiple it by 1.25. 125 X 1.25 = 156.25
  4. You need a fuse that can handle 156.25A. But they only make 150A and 200A fuses. So what you will need to do is round up to 200A fuse. Be sure to use inverter cables that can handle 200A, so if a fault were to occur, the cables can carry 200A to the fuse. 


100 Amp Fuse and Holder

150 Amp Fuse and Holder

175 Amp Fuse and Holder

200 Amp Fuse and Holder (recommended for 2,200W inverter)

250 Amp Fuse and Holder

300 Amp Fuse and Holder

High Quality Fuse Block

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Connect 12 volt appliances here

Click here

​

Required Circuit breaker for
​Solar Charge controller to Battery

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If you use the recommended 40 amp solar charge controller, you will need to install this 50 amp circuit breaker between the solar charge controller and the battery, on the positive wire. 

Click here

bus bar

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​Connect multiple components on a wooden board with a bus bar
Click here for a wide selection of bus bars for every situation
 

​Solar Panel Mounts:

Every vehicle is different, so check out my book and this page (click here) to figure out how to mount your solar panels

Battery Monitor:

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This device will tell you how much power you have left before your batteries go to zero. Simply attaches at the main negative lead of your battery bank.

​
Click Here to purchase



If you want a higher quality battery monitor with bluetooth connectivity and data logging, check out the Victron Smart Shunt instead. It does cost more, but it is a fantastic device that I use on all of my systems: Click Here

Required Tools:

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Precision Wire Stripper

8-22 gauge wire
Click Here
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Hammer Type Crimper
Can crimp up to 4/0 gauge wire, and it is much cheaper than other large wire crimpers. If you plan to build only one system, this is the tool for you. 

Click Here
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High quality manual force crimper
This crimper will crimp any standard/non-standard, insulated/non-insulated connector. 

Click Here ​
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​Standard Size Crimp Connector set
There are cheaper crimp connector sets available, but they are junk! Spend the extra money and buy a high quality set of connectors. The cheap chinese ones will fail and I have had it happen before. This is what I currently use:
Click Here
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Large Size Crimp Connector Set
Use this set to connect large wires together, such as inverter or solar charge controller wires. 
Click Here

Other Accessories

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12 volt USB charge strip
 Click here
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46 Liter Dometic Solar Power Fridge
 Click Here

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Battery bank to cigarette light adapter
Click Here
​
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Color Changing LED lights
$14.99 Click here


or
​
White LED light strip
Click here

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Power panel with switches and USB/cigarette lighter plug
Click Here


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Super useful clippers. Use them to cut anything small.


Click Here

Full Construction Demonstration!


Copyright  Prowse Publications LLC © 2025
Prowse Publications LLC (www.mobile-solarpower.com) is a participant in the Amazon Services LLC Associates Program,
​an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com
I make a commission for sales made through affiliate links posted on this website
  • Home
  • DIY Solar Packages
    • EG4 Off-grid System Builder
    • EG4 Hybrid System Builder
    • Mobile Systems >
      • 48V 3kW Handtruck System
      • The Minimalist (great for small vans and cars)
      • The Classic 400 Watt (RV's, Vans, Buses)
      • 400 Watt w/ Alternator Charging
      • The Off Grid King (Power Anything!)
  • Solar Batteries
    • 48V Server Rack LiFePO4
    • 48V Vertical Mount LiFePO4
    • 12V Lithium Batteries
    • Battery Capacity Testers
  • Solar Components
    • 50-250W Solar Panels
    • 300W+ Solar Panels
    • Ground Mount Solar Racking
    • Inverters
    • Solar Charge Controllers
    • Battery Chargers
    • Wire and Connectors
    • Fuses and Circuit Breakers
    • Tools
    • Battery Monitors
    • Automatic Transfer Switches
    • Battery Isolators
    • Raw LiFePO4 Cells
    • BMS
    • Solar Friendly Air Conditioners
    • 12v Fridges
  • Free Solar eBook
  • Plug-N-Play Systems
    • Full Size Systems
    • Ultra Portable Systems
  • Videos
    • Solar Power for Beginners
  • The Forum
  • How to Mount Solar Panels to a Vehicle
  • Contact Me
  • Policies and Disclaimers