I'm in the process of setting up a solar grid for my sailboat, but I'm a total newbie when it comes to this kind of project. I've been doing a lot of research and trying to piece everything together since I need to handle both the installation and maintenance to keep costs down. I've created a diagram to outline my plan, even though my handwriting is questionable! After conducting an energy audit, I've determined that my system should adequately meet my needs, even during low sun conditions. I'm still trying to figure out the cabling because I need to confirm the lengths that'll run throughout the boat, but I have a general idea and have sized the fuses accordingly.
Here's a quick overview of my setup:
- **PV 200W 12V 10A x4 in 2 Series-Parallel**
- Each series at 12V 20A
- Parallel at 24V 20A
I have components outlined for the system including a charge controller, batteries, fuses, and inverter. If anyone has any feedback or suggestions, I'd appreciate it since I'm still learning and I wouldn't be surprised if I made some mistakes!
1 Answer
It looks like you're on the right path, but I noticed a small misconception. In a solar setup, series connections increase voltage, while parallel increases amperage. So your configurations before the Y connectors are actually running at 40V and 10A, not the other way around. Also, remember that most "12V" panels are technically higher (about 18-20 volts), which is important to keep in mind!
Regarding the fuses, the 30A fuse after the Y combiner might be better as a breaker. This is because solar panels typically don’t spike significantly in amperage when shorted. A circuit breaker would allow you to disconnect in emergencies, plus it can be handy when working on wiring.
Also, keep in mind that a 30A charge controller is able to handle around 440W with a 12.8V battery, but with 800W of panels you're oversizing it, which might actually work if you anticipate shading often.
Make sure you have everything sized properly to avoid any potential issues!
Thanks for the insights! So if the panels are indeed higher than 12.8V, the 100V controller should work fine, right? And about fuses versus circuit breakers, I thought they were the same, but I might've misunderstood. The ones I've been looking at do have switches to cut the current manually, which helps. I tend to lean towards having the panels oversized for efficiency. Would switching to a 100A or 50A controller make sense for my setup?