My New DIY Portable 400 watt Solar Generator (with pix)!

[Rascal]

My fully portable DIY off-grid solar generator project is all but complete! I have a few i dotting and t crossing things to do but I tested it this afternoon and it's working! By the time I finished testing and got round to taking pictures it had completely topped off my battery bank and shut off the current from the array.

The battery bank is two Battle Born 100 amp/hour batteries wired in parallel for a combined 200 amp hours. The batteries and electronics fit into a chest I made for the purpose. I'm not happy yet with the wheels I put on the array assembly when it's folded up so I'll fuss with that. I'm going to try a Google Drive link vs. uploading pix in order to save space on the forum. If that doesn't work then I'll upload.

I'm stoked!

DIY_SolarGenerator - Google Drive

drive.google.com

 

[Bob142]

You should be stoked, that's nice work!

Your array framing makes it look like art when deployed. Judging by the vast array of well-organized tools I see in the workshop, I bet this isn't your first DIY project.

 

[Supervstech]

My fully portable DIY off-grid solar generator project is all but complete! I have a few i dotting and t crossing things to do but I tested it this afternoon and it's working! By the time I finished testing and got round to taking pictures it had completely topped off my battery bank and shut off the current from the array.

The battery bank is two Battle Born 100 amp/hour batteries wired in parallel for a combined 200 amp hours. The batteries and electronics fit into a chest I made for the purpose. I'm not happy yet with the wheels I put on the array assembly when it's folded up so I'll fuss with that. I'm going to try a Google Drive link vs. uploading pix in order to save space on the forum. If that doesn't work then I'll upload.

I'm stoked!

DIY_SolarGenerator - Google Drive

drive.google.com

google drive is great so the full size pictures can be seen, but uploading to the forum keeps the pics preserved for as long as the forum exists, so please upload pics also!
2560ish Wh battery storage, 400W solar, 3000W inverter, NICE!
Be sure and include a ground cable to prevent shocks when running devices outside. That inverter needs grounding of the case.

 

[Rascal]

You should be stoked, that's nice work!

Your array framing makes it look like art when deployed. Judging by the vast array of well-organized tools I see in the workshop, I bet this isn't your first DIY project.

Thank you very kindly! In addition to being a ham radio operator, I'm also a hobbyist woodworker who enjoys making furniture. I'm always looking for new reasons to make sawdust! I fussed with the wheels today and got something I'm happy with. I saw a 2 wheel dolly a metal worker had made for transporting a large maple conference room table. I did the reverse of what his looked like but it's perfect for what I need to do. I also got the protective panels on today, and refactored the handles that I needed to maneuver the array on the dolly.

Next thing I need to think about is something I should have though of before. How to eliminate RFI. That can play heck with my radios! I'll upload the files as the moderator suggested.

 

[Rascal]

google drive is great so the full size pictures can be seen, but uploading to the forum keeps the pics preserved for as long as the forum exists, so please upload pics also!
2560ish Wh battery storage, 400W solar, 3000W inverter, NICE!
Be sure and include a ground cable to prevent shocks when running devices outside. That inverter needs grounding of the case.

I will, and thanks for the suggestion.

 

[Rascal]

Per the moderators suggestion, I'm uploading pix of the project. Enjoy!

 

[SolarOhio]

Be sure and include a ground cable to prevent shocks when running devices outside. That inverter needs grounding of the case.

I have a similar portable setup. In my shop, I can tether it to existing grounding, but what can you run a grounding cable to in a mobile situation outside with no rod available and a non-conductive case?

 

[Rascal]

I often set up portable field ham radio stations and I ground whenever possible, which is almost always. I use a stake which is basically a huge nail. Take a hose clamp and strip one end of your ground wire and clamp it to the stake and drive it into the ground. Attach the other end to your grounding buss as appropriate. For my radio stations I've used 10 AWG wire and a 45 amp Anderson PowerPole connector. I get the green ones and use just one instead of a pair. That way you can have a wire permanently attached to the buss and just hook it up via the PowerPole connector in the field. I'm not sure if that's actually a big enough wire but any ground is better than no ground.

One more thing... ground is not at ground level. I live in Las Vegas and we have very poor ground here. You can water your ground stake to improve that. If you live in Mississippi ground it probably at ground level. But not in the desert! You can set up an Ufer ground but that's very hard to do for a field station.

Hope this helps!

 

[svetz]

Nice job! Any lessons learned you can share? Let us know what you do for the RFI and how well it works (not a HAM, but here's what my installer did: https://diysolarforum.com/threads/an-enphase-ensemble-installation.3603/post-36150).

 

[Rascal]

Nice job! Any lessons learned you can share? Let us know what you do for the RFI and how well it works (not a HAM, but here's what my installer did: https://diysolarforum.com/threads/an-enphase-ensemble-installation.3603/post-36150).

Thanks for the tip! I haven't tested with a radio yet, but that's on my agenda. I also have some ferrite beads (mix 31) and might need to get some mix 75 for the HF spectrum. I generally use 20, 40, and 80 meters on HF, as well as the 2 meter (VHF) and 70 centimeter (UHF) bands. I also mess around with mesh networking in the 2.4 and 5.8 ghz bands.

I think my lessons learned are yet to come! For now, I'm fairly pleased.

 

[SolarOhio]

I often set up portable field ham radio stations and I ground whenever possible, which is almost always. I use a stake which is basically a huge nail. Take a hose clamp and strip one end of your ground wire and clamp it to the stake and drive it into the ground. Attach the other end to your grounding buss as appropriate. For my radio stations I've used 10 AWG wire and a 45 amp Anderson PowerPole connector. I get the green ones and use just one instead of a pair. That way you can have a wire permanently attached to the buss and just hook it up via the PowerPole connector in the field. I'm not sure if that's actually a big enough wire but any ground is better than no ground.

One more thing... ground is not at ground level. I live in Las Vegas and we have very poor ground here. You can water your ground stake to improve that. If you live in Mississippi ground it probably at ground level. But not in the desert! You can set up an Ufer ground but that's very hard to do for a field station.

Hope this helps!

Good setup — I was thinking of something just like that. But it makes me wonder why most commercial “portable solar generators” don’t have any sort of ground.

 

[Gazoo]

Good setup — I was thinking of something just like that. But it makes me wonder why most commercial “portable solar generators” don’t have any sort of ground.

That's a very good question. Anyone have an answer? I would love to do a portable DIY UPS with one of the higher end inverter/chargers. Don't need solar right now but could easily be added on later. But how would one keep safe with no grounding? GFCI? For example how do Ecoflow and Bluetti do it?

 

[Supervstech]

That's a very good question. Anyone have an answer? I would love to do a portable DIY UPS with one of the higher end inverter/chargers. Don't need solar right now but could easily be added on later. But how would one keep safe with no grounding? GFCI? For example how do Ecoflow and Bluetti do it?

If the unit doesn’t have a ground terminal, it is an isolated ground unit. The GFCI setup isn’t relevant. Isolated ground setups do not have the energy path grounded, so you won’t have a current path. Current won’t leak, and you won’t get shocked.

the issue of grounding arises on DIY generators when non isolated inverters are used, and ground fault potential is present.

So, IF the inverter has ground prongs, and bonding mounts, they are important to be used.

 

[Rascal]

If the unit doesn’t have a ground terminal, it is an isolated ground unit. The GFCI setup isn’t relevant. Isolated ground setups do not have the energy path grounded, so you won’t have a current path. Current won’t leak, and you won’t get shocked.

the issue of grounding arises on DIY generators when non isolated inverters are used, and ground fault potential is present.

So, IF the inverter has ground prongs, and bonding mounts, they are important to be used.

Great comment! That raises a question for me. My inverter has a ground terminal and that's the next thing I'm going to hook up. Do I need to also ground the SCC? There are no ground terminals for that on the unit.

What I do with my radio stations, is run a wire from all of the cases to a common terminal, then from that terminal to my ground stake so there is only one path to ground. I'm wondering if I need to do that for the SCC as well as the inverter.

A ham operator in my radio club has an outstanding presentation on lightning and the importance of bonding and grounding. His super slo-mo of lighting is awesome! You can see the step leaders coming down from the clouds and the streamers coming up from the ground. (I always think of them yelling 'hit me! hit me!)

 

[Supervstech]

If it is a plastic device connected to bonded grounded panels, I doubt there is a path to ground on the scc.
Remember... shocks come from energy returning to source, not just to ground.
The only way SOLAR energy electrocutes is if there is a ground common leg of the energy in a path your body interrupts.

For lightning, the panels should be grounded.

For static discharge, anything METAL should be grounded.

 

[Rascal]

Thanks for that! I'm not sure exactly how to do that with the panels. They're in wooden frames, wired in parallel with the collected pos/neg wired to the SCC. I used 50 amp Anderson Powerpoles as I expect to connect/disconnect relatively frequently and wanted to save stress on the MC4 connectors. I have a 20 foot pair of solar wires (8 AWG) from the panels to the Anderson plug. The chest the batteries, SCC, and inverter are in is also wooden.

I think I could use copper straps to bond the metal frames of the panels (aluminum) and ground that but it would have to be separate from the inverter ground. That would seem to violate the single path to ground rule. I'm also concerned about flexing the central bond as the panels are folded and unfolded as I take them down and set them up. I guess I could bond the two panels on each frame and then wire those bonds to a common ground.

Do you think it would be feasible to run a ground wire from the panel frames to a central ground terminal at the chest and then take everything from there to the ground stake?

 

[Supervstech]

Thanks for that! I'm not sure exactly how to do that with the panels. They're in wooden frames, wired in parallel with the collected pos/neg wired to the SCC. I used 50 amp Anderson Powerpoles as I expect to connect/disconnect relatively frequently and wanted to save stress on the MC4 connectors. I have a 20 foot pair of solar wires (8 AWG) from the panels to the Anderson plug. The chest the batteries, SCC, and inverter are in is also wooden.

I think I could use copper straps to bond the metal frames of the panels (aluminum) and ground that but it would have to be separate from the inverter ground. That would seem to violate the single path to ground rule. I'm also concerned about flexing the central bond as the panels are folded and unfolded as I take them down and set them up. I guess I could bond the two panels on each frame and then wire those bonds to a common ground.

Do you think it would be feasible to run a ground wire from the panel frames to a central ground terminal at the chest and then take everything from there to the ground stake?

The single path to ground rule is for bonded neutral grounding.
Panels not attached to the home can have their own lightning ground path. As long as it is only connected to the metallic structure and panel frames.

 

[Gazoo]

If the unit doesn’t have a ground terminal, it is an isolated ground unit. The GFCI setup isn’t relevant. Isolated ground setups do not have the energy path grounded, so you won’t have a current path. Current won’t leak, and you won’t get shocked.

the issue of grounding arises on DIY generators when non isolated inverters are used, and ground fault potential is present.

So, IF the inverter has ground prongs, and bonding mounts, they are important to be used.

Thanks...makes perfect sense and now I know what to look for.

 

[dadgolf]

Awesome build. What gauge wire did you use to connect the batteries in parallel?

 

[Rascal]

Awesome build. What gauge wire did you use to connect the batteries in parallel?

Thanks! I'm pretty pleased with it!

I used marine grade wire throughout the build. I used 2 AWG for the battery bank connections, 4 AWG for the inverter/DC power distribution, and 6 AWG for the solar charge controller connections. I wanted to use 4 AWG for that but the terminals are too small. I also wanted to use ferrules on the SCC connections but they wouldn't fit. As it turns out, when I disconnected one of the wires to work on something else, it turns out that the terminal connection contains the wire in a square and presses down from the top and makes a nice solid connection. The incoming connection from the solar panels is 8 AWG (not marine grade, but the stiffer solar wire).

Cheers!

 

[JoeHam]

Thanks for the tip! I haven't tested with a radio yet, but that's on my agenda. I also have some ferrite beads (mix 31) and might need to get some mix 75 for the HF spectrum. I generally use 20, 40, and 80 meters on HF, as well as the 2 meter (VHF) and 70 centimeter (UHF) bands. I also mess around with mesh networking in the 2.4 and 5.8 ghz bands.

I think my lessons learned are yet to come! For now, I'm fairly pleased.

I think mix 31 and 43 have you covered. I wouldn’t bother with mix 75.

First google hit:

All About Ferrite

Rings, beads, cores ... find out exactly what ferrite is and used for.

www.nutsvolts.com

 

[Rascal]

I think mix 31 and 43 have you covered. I wouldn’t bother with mix 75.

First google hit:

All About Ferrite

Rings, beads, cores ... find out exactly what ferrite is and used for.

www.nutsvolts.com

Thank you very much! That looks like a great article!

 

[namesgolden]

I use a stake which is basically a huge nail.

If you have a 1/2" impact you can use huge lag bolts. Makes the process much easier.

Idk about you but I always carry my impact on road trips. Makes changing a tire trivial.

 

[Rascal]

If you have a 1/2" impact you can use huge lag bolts. Makes the process much easier.

Idk about you but I always carry my impact on road trips. Makes changing a tire trivial.

That's a great idea! Thanks! I would never have thought of it. I don't have a 1/2 inch impact but I do have a 3/8 Bosch that would probably do fine. I used it to crimp the lugs when I was making up the wires for my system. Might be a good way to secure the array too when I want to leave camp for a hike or something.

 

[namesgolden]

That's a great idea! Thanks!

I actually learned it from some burners. Many of them anchor all kinds of things that way, apparently works great in the desert.