EastTexCowboy
Solar Wizard
I'm going to do a mobile cart build based on the video Will did with the EG4 3K. I could simply duplicate everything he did and I'd have a great system, but I'd like to refine the design a little with some specific goals in mind. I'm hoping for some input from the brain trust on this forum. I have no doubt I'll get some really innovative ideas. I'll document the build here, although it's so simple I can't see that taking a lot of effort.
This build is going to be for my daughter and her husband who have zero experience with solar but considerable experience with power outages. They're in north central Arkansas, which is a ways from me so I want to keep it simple and hopefully fairly reliable. Here's where I'm at -
Here's Will's video in case you haven't watched it. He also has a follow up video.
@Gavin Stone has done a couple videos on the EG4 3K inverter as well. If you haven't seen those they're very informative. Here's the first one -
This build is going to be for my daughter and her husband who have zero experience with solar but considerable experience with power outages. They're in north central Arkansas, which is a ways from me so I want to keep it simple and hopefully fairly reliable. Here's where I'm at -
- Inverter - I've looked at a lot of other options but the EG4 3K seems to be the best option due to physical size, weight, and capabilities. From the posts here and videos it seems to be reliable. I'm open to suggestions on this as well as any of the build.
- Battery - Will used the Trophy and gave his reasoning which I think was primarily the battery connections. The Trophy has been on backorder for a while so I'm looking at the SOK from Current Connected. I'm an EG4 fan but the battery connections are not positioned very well for this application. The SOK seems solid, has decent connections for the application, and Dexter is very active here so I have no qualms about going that direction.
- Connections - There are three I/O connections needed - (1) AC input, (2) AC output, and (3) PV input.
- AC Input - Will used a basic 120v cord which would certainly work. But I'm thinking maybe a mounted connection in a metal switch box or similar bolted to the cart frame which would allow the user to connect with a standard extension cord without any cords hanging out of the unit.
- AC Output - Again, Will simply connected a power strip or surge strip which would certainly work. I'm thinking a two gang metal switch box, once again mounted to the cart frame. Mostly just to clean it up and not have cords dangling.
- PV Input - I'd like something a little easier to connect and disconnect than MC4 connectors. @OffGridForGood suggested a 175A Anderson connector, which I'll admit looks pretty good. It's going to mean a dangling cord but it would be a pretty simple solution. I also thought about mounting something like a male NEMA 14-30R on the cart and building a matching cable with the MC4 connectors on the other end to connect to the panels. I know, I'm running out of room on this little cart to mount stuff. I'd love some input or ideas on this.
- Mounting the battery
- The orientation has bugged me a little on this because if you mount the battery so the connectors are towards the cart and the LED screen is oriented where you can read it standing in front of the cart you won't be able to lay the cart down on its back while using it. The battery would be upside down. I don't know that this is a big deal but I can see people laying it down on its back. I suppose I just need to advise them not to do that.
- Will mounted his with a ratchet strap. I'm trying to come up with another way but I've been struggling. If I had a metal brake I could make a sheet metal box, but I don't have one. I can't really justify one. It would be nice to have it easy to remove the battery for loading it in a pickup and the strap would be fine for that but then you have to connect and disconnect the battery cables so maybe not.
- Solar panels - I haven't thought about this a lot. I may not even give them any panels at first and just let them charge from the grid. If I do it's probably going to be some smaller output panels due to size, weight, storage space. I have some spare 445w panels I can use just to test it but they're heavy beasts. Maybe I'll just order a bunch of small panels then I can have some for myself for future projects, because you know I'm going to want to build one of these for myself.
Here's Will's video in case you haven't watched it. He also has a follow up video.
@Gavin Stone has done a couple videos on the EG4 3K inverter as well. If you haven't seen those they're very informative. Here's the first one -