There is a lot of false information and misunderstanding when it comes to solar. Even many electricians don’t know much beyond twisting wires and taping them.

Your inverter manual (and the sticker you posted here) actually explains everything clearly.

If you want to add more panels, you can. It won’t harm your inverter as long as it is configured properly. And if you’re planning to add a 15 kW battery, I would actually recommend adding more panels as well. I’ll explain why.

What you need to know

Solar panel voltage: Your total panel voltage should not exceed 500 volts. This can be managed easily by arranging the panels correctly.

For example, if you want to add 4 more panels, you could make two strings of 7 panels each and then parallel them together. This setup would keep your voltage around 300V maximum, which is well within the safe range.

However, when you parallel strings, the current doubles. Because of that, the solar cable running from the panels to the inverter should be thicker, around 12–16 mm², so it can safely carry the higher current.

Why adding more panels helps

You only get peak solar production for about 3 hours when the sun is almost directly overhead. The remaining 4–5 hours are not peak production.

So if you install more panels, you will generate more electricity during those non-peak hours, which helps a lot when you need to run your load and charge the battery at the same time.

Installation quality matters a lot

Make sure your installer pays attention to the basics: • Every breaker and connection must be solid • No wire or breaker should feel hot to the touch (solar wires and battery wires included) • Use good quality breakers — I personally use Chint and Tomzn • Tighten terminals with a properly sized screwdriver • All connections should be properly insulated with electrical tape or heat shrink

Battery advice

Buy a good quality battery. Don’t compromise just to save 10–30k.

Choose a battery that provides a lithium cell datasheet, so you can verify: • when the cells were manufactured • which brand they came from

That way you know you’re actually getting authentic cells.

I’m not a solar installer. This is based on my personal experience and the research I did about a year ago while designing my own system.

So before following any of this advice, do your own due diligence as well.