How to build a Portable 420 watt Solar Power Generator . Step by step Instructions,perfect for beginners

This project goes over the build of a 240W Solar Generator made out of an army box. The box is large enough to hold a 240-watt deep cycle battery.


There are some basic tools that you are going to need to build this generator. Number one tool, you’re going to need a drill. If you don’t have a drill, you can find one at Home Depot, you don’t have to spend a lot of money. The next thing you’re going to need is a screwdriver. Next, you’re going to need a wire cutter, a wire cutting, and a stripping tool. And it’s also got a crimper on there.

To drill the holes in the metal ammo box, you need a step-up drill bit that can drill different-sized holes, using all the same drill bit. You will need a pair of pliers which might be handy when you are cutting and manipulating wires and then basic wire cutters which also we have on the pliers.

The next thing that you’re going to need is the heart of the generator, which would be the battery. Now, this is a Rayovac deep cycle battery.I recommend that you use a V max deep cycle battery.The next thing you’re going to need is a USB port. This is a two-port device, it’s got a one amp outlet and a 2.1 amp outlet. You’re also going to need a 12-volt outlet. Faceplate, blade fuse holder, terminal connectors, switch, self-tapping screws,14 gauge 17 amp black and red wires.

We use a 3 prong switch, one of the gold in color which is the negative terminal, and the other two positives.The purpose of the switch is to control your USB outlet. And it’s what turns the USB outlet on and off.

The positive terminal on the USB outlet is first going to run to the positive terminal on the switch. Now the purpose of this switch is to break the electrical current when you turn it off. So the positive terminal goes to the positive terminal, then the second positive terminal on that switch goes to the positive terminal on the battery. So you’ve got a flow of electricity going from positive through this switch to the positive terminal on the USB port.

The negative terminal on the switch goes to the negative terminal on the battery. The only purpose of that terminal is to control the LED light on the switch, it needs both positive and negative electrical currents in order to turn that light on.

Similarly, for the 12V port, the positive connector goes to the positive terminal going to the positive terminal on the battery.

Let’s start the build.



Start with drilling holes for the ports using the faceplate. Get your marker and simply trace the inside from both the top and the bottom. So that’s where your holes are gonna go. Now we want to find the exact centers when we’re drilling.

Insert the 12V and the USB outlet into the holes which we have just drilled. Now, these ports have a little ring that screws on the back. This is what holds it in place.



The next thing we’re going to install is the power switch and SAE Solar Power Socket and the voltmeter.




To begin wiring our tabs batteries, you’re going to need a few things. Number one, you’re going to need a battery. Number two, you’re going to need your quick disconnects. You’re going to need your squeeze connector,your wire cutters, and stripping tool and you’re going to need black and red wires.

Place the max battery into the ammo box. So we’ve got everything in place, we have our ports in place, we have our battery in place, we’ve got our switch in place, and our voltmeter. We’re gonna start by wiring the USB port.



The positive connection of the USB port is connected to the positive of the switch which is further connected to the positive of the battery. The negative connection of the USB is connected to the negative of the battery.

This switch will break the flow of electricity on the positive side and that’s what’s going to turn our USB port on and off.

Using squeeze connectors, USB port negative terminal is now connected to the same negative terminal as the 12-volt port. Connect the positive terminal from the switch to the positive wire which is coming from the 12-volt port and continue that positive flow from the switch to the positive terminal on the battery.

So we now have our USB port and our 12-volt outlet connected to the battery through the power switch. We’ve got the negative terminal of the USB port, going to the negative terminal on the battery, we have the positive terminal of the USB port. Then we’ve got a positive going from the switch to the positive on the battery all through quick disconnects.

The negative terminal on the battery going to the negative terminal on the switch simply allows the switch LED light to turn on without this negative current flow of electricity. This  LED light has no power. So we want to give that light power by connecting to the negative terminal on the battery.

The negative of the Voltmeter is directly connected to the battery and using insulated clamps, we connect the positive wire that’s already running to the switch for the USB port. Now we want to connect to the positive wire leading to the positive terminal on the switch so that the voltmeter will turn on and off with the switch button.

Next, we’re going to cover the SAE port. We want to be able to have the battery charged when we plug this into a charger. Using the squeeze connector we connect the positive to the positive terminal of the battery. And the same thing for the negative, you would take your squeeze connector and connect to the negative.



Lastly,A 15amp fuse is used to protect the generator from overloading. If you connect at a current that is too high for their internal wiring to handle, the fuse will break and it will stop all electrical current from flowing. So if anything goes wrong in any of this wiring, it has to get past the fuse before it reaches the battery. So if there’s anything that’s overheating, or overloading this fuse is gonna blow and it’s gonna protect your battery from being damaged.



The next step is connecting a solar panel to your generator. We connect the panel to the charge controller and then from the charge controller to your ammo generator. A charge controller prevents the battery from overcharging. You don’t want to get over 15 volts.

Here we use Renogy 30 watt solar panel, this panel comes by default, with an SAE connector on the back. This is the same kind of connector that plugs into your generator.

Connect the wires coming out of the Solar Panel into the charge controller. Next is connecting the SAE cord from the generator
to the charge controller.

So you just put the panel on the charge controller, the charge controller into the generator, and you’re done.

If you want the whole system to be portable, say you want to be able to take your solar panel and your generator camping, you want to keep things as simple as possible, you could actually mount the charge controller directly onto the back of your panel.

Image Credits : Reconstruct Your Life

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