Complete DIY 48V ​
Offgrid Solar Power System

If you wish to build the ultimate offgrid solar power system, look no further:
  • All-in-one units make setup a breeze. Each unit has it's own Inverter, MPPT, Transfer Switch and Battery Charger.
  • Budget Friendly. Compared to a victron, this system is 3X cheaper!
  • You can scale this system. Use 1-6 units for any size you wish. 
  • Use this system to backup your home (with an electrician installed transfer switch) or to run an EV or anything you wish!
  • Battery Pack uses LiFePO4 which will last 20+ years. Even at the end of its cycle life, it will work just fine (unlike lead acid which goes bad and needs to be replaced). 
  • High efficiency. These inverters are rated at 91% efficiency, but in my testing, they pull around 94% efficiency. 
  • Communication system is built in and takes only one cable. This will allow the batteries to control the all in one system. 
  • Mostly beginner friendly. If you are hestitant to do the AC wiring, hire an electrician. Show them this page or the manual of the EG4 all in one, and they will be able to figure it out. 

Because this system is scalable, it can handle a wide array of solar and AC load sizes:
  • Max PV input for 1 unit is 8,000W. For 2 units, 16,000W. If you have 6 units, you can use 48,000W of solar panels!
  • Max AC output for 1 unit is 6,000W at 120V. For 2 units, 12,000W (either 120/240V). 3 Units can create 3 phase, 18,000W. If you have 6 units, it will output 36,000W.
  • Each Unit has a 110A 48V battery charger.
  • Each Unit can also be used as a UPS when bypass is enabled. This is great for people who want to use this as a backup battery without solar. 
  • Recommended battery size is 30kWh. But you can use a smaller battery if you do not have large loads. Even a 10kWh 48V battery can power 2 units. 
Be sure to check with local laws and regulations for your electrical code. Some places are more strict or lax than others! If you need a code compliant system, check out my other blueprint by clicking here​

Complete 48V Package Parts List

  1. EG4 6000XP All-in-one Solar Power System: Click Here to Purchase
  2. 2/0 AWG Inverter Cables: Click Here to Purchase

48V LiFePO4 Battery Options:
  1. Server rack battery: Click Here
  2. Vertical Mount Battery: Click Here
AC Panel Parts List:
  1. Load Center w/ Main Breaker: Click Here to Purchase
  2. ​40A Circuit Breaker for All-in-one: Click Here to Purchase
  3. 3/4 Flex Conduit w/ Adapters: Click Here to Purchase
  4. 3/4 to 1in Reducing washer (8X required): Click Here to Purchase
  5. 15 ft of black THHN 6 gauge copper wire: Purchase from Local Hardware Store
  6. 15 ft of white THHN 6 gauge copper wire: Purchase from Local Hardware Store
  7. 30 ft of green THHN 10 gauge copper wire: Purchase from Local Hardware Store

How to Build it. Watch this video:

48V System Blueprint

Load Center

Combiner Box

Inverter Wiring

The ac output is in parallel, so be sure to connect the L1's to one bus bar on your combiner box, and L2's to the other bus bar. If you switch these wires, you will have a bad day! Notice the wiring configuration on the combiner box breakers. This is how it should look!

Server Rack Battery Configuration
This part is easy! Just have a friend help you slide the batteries into the rack, and connect the batteries to the bus bar. Watch the video on the left to learn how to do this safely because there are lots of small tips and pointers to doing this safely. 

This video also covers how to use the precharge resistor circuit in the batteries! This is a crucial step when connecting this many batteries to your system! Follow the step by step procedure to do this safely. 

How can I use this system to
back up my home legally?
​How do I ground this system?

The best method to use this system in a legal fashion, is to hire a licensed electrician to install a transfer switch for your homes critical loads. Then have the electrician connect the transfer switch to your offgrid solar power system's load center. They will run the proper size conductors, and ground the system to NEC code.

This can be quite tricky, and will depend on where your system is located, if you have multiple buildings, and if you are in a lightning prone area. They will install a ground rod if they feel that it is necessary. Do not earth ground your system if you are not qualified.

​You could also have the electrician install what is called a RCD (residual current device) or SPD (surge protection device) if your system needs it. 

I think most things can be done on your own, but not this. There is a lot to understand, and you cannot screw this connection up. Setup the system above as an offgrid system, and have an electrican finish it up.