I'm about to order my solar inverter and panels, but I'm feeling a bit anxious about whether I've got everything covered. I'd really appreciate some feedback from the community regarding my setup:
- 18 panels, each 450W, with 8 facing south and 10 facing west (you can check the datasheet [here](https://static.csisolar.com/wp-content/uploads/2022/09/05084502/CS-Datasheet-TOPHiKu6_CS6.1-54TD_v1.3_EN.pdf)).
- The total system size is 8.1kW.
- I've chosen a SolarEdge 7600 inverter (7.6kW), and you can find the datasheet [here](https://knowledge-center.solaredge.com/sites/kc/files/se-solaredge-home-wave-inverter-single-phase-with-setapp-datasheet-nam.pdf).
- I'll also use S500B power optimizers (datasheet [here](https://knowledge-center.solaredge.com/sites/kc/files/se-power-optimizer-s-series-datasheet.pdf)).
- The optimizer ISC is rated at 15A, while the panel ISC is 14.55A, giving me a DC/AC ratio of 1.06.
What's really bogging me down is the DC/AC ratio. I know it's on the lower end, but I'm not sure what the implications are of having a larger inverter aside from the extra cost. Any insights would really help me out!
2 Answers
Make sure you're not putting more than 10 panels in a single string due to voltage limits. Your inverter can take up to 480V DC but only 400V after accounting for temperature fluctuations. So, it’s best to create two separate strings — one with 8 and the other with 10 panels — and connect them to different MPPTs. And definitely don’t mix panels facing different directions in the same string.
You’ll want to think about how you’re wiring those 18 panels to your inverter. Since you can have up to 25 optimizers on one string, it might seem okay to put them all together. But remember, each string has a max power of 5700W, so you might actually end up needing two separate strings instead.
That makes sense! I'm also a bit confused about the stringing process. I'm assuming I can just mix them in one string since the optimizers allow it, right?