Hey everyone! I'm diving into a little solar project and have some basic questions. I'm looking to set up a small 50W solar panel to power string lights (12V, 15W) in a part of my garden that's hard to access. The plan is to connect the solar panel to a charge controller linked with a 7Ah 12V lithium iron battery, and then have the lights hooked up to the load terminals on the controller.
Here are a few things I'm wondering about:
1) Is it necessary to include fuses between the battery and the controller, the panel and the controller, and the lights and the controller? I've heard that fuses might introduce weak points in the system.
2) Can I use 3 core cables for this DC setup? I have some on hand, and I'd keep the ground wire insulated.
3) Is it okay to mount the solar panel vertically on a south-facing wall? I know it's not the ideal position, but it's what I want for aesthetics.
4) Are there any major issues with my plan? I'm a beginner with solar energy, so I'm treating this as more of a fun experiment.
Thanks for any help!
4 Answers
Consider using DC breakers instead of fuses. They're a reliable option to protect your system without introducing too many weak points. Just do some research to find what's best for your setup!
Just a heads up: if you're using a lead-acid battery, it might struggle to run your lights for even 3 hours. With lithium, it's a bit better, but still, you should watch your usage if you're planning on more extended use.
Yes, including fuses is a good idea for safety. For your setup, automotive bus fuses that match the cable gauge and length should work just fine. Just make sure they are rated appropriately!
Yep that was exactly my plan. Thanks 🙂
Solar panel current is limited, so fusing a single panel may not be needed in every case.
Keep in mind that if you're mounting the panel vertically, you might only get about 25W of max output. A good rule is to aim for a panel that can generate three times your usage to be safe. Since you'll be running 1.25A at 12V (around 16W), I’d recommend at least a 100W panel to ensure you have enough power, especially mounted vertically. Also, your battery should ideally be larger than 7Ah for longer runtimes.
Ok thank you!
It’s lithium, but the most the lights would need to be on is 2-3 hours.