Can I add 4 more solar panels to the existing system? Now the solar panels (16 pieces) make 6 400 W of power (according to documents) and a voltage of 432 V (calculated at negative temperatures of -20). If I add 4 more solar panels, the power will become 8 000 W and voltage 540 V (calculated at negative temperatures of -20). The inverter has the following indicators. I think 540V voltage is within the range (125-550), but the power is a big 8 000 W. Will increasing the number of panels damage my inverter?
Solar system:
1. Hybrid inverter 5,000 W. - Max. Input Power (W)-6500
Max. Input Voltage (V)580
MPPT Operating Voltage Range (V)125~550
Start-up Voltage (V)125
Max. Input Current per MPPT (A)14
Max. Short Circuit Current per MPPT (A)17.5
Number of MPP Trackers2

2. GoodWe SECU-A(4.8kWh) battery

3. 16 pieces VITOVOLT 300 Type M400WE (Pmax. 400 W, MPP-spanning Umpp 38.6 V, Umpp 10.36 A, Uoc 46.4 V) The panels are arranged in 2 strings of 8.

Ok, so AFAIK the biggest thing with panels is making sure you stay under the MPPT max voltage. Since current is drawn, not pushed, extra current current capacity shouldn't be an issue. If anything, it may help fill in for any inefficiencies or give you a little more umph when the panels aren't getting ideal sunlight. So going from 2 strings of 8 to 2 strings of 10 shouldn't be an issue but this is all from a theoretical point of view and would advise waiting for someone with more practical experience to confirm  👍

MPPT Operating Voltage Range (V)125~550

MPPT 1 - 46.4 V x 8 = 371.2 v

MPPT 2 - 46.4 V x 8 = 371.2 v

MPPT 1 + MPPT 2 = 742.4 v

Looks like you already oversubscribed, unless the limit of 550v is per MPPT

17 minutes ago, Dieter said:

Обхват на работното напрежение на MPPT (V) 125~550

MPPT 1 - 46,4 V x 8 = 371,2 v

MPPT 2 - 46,4 V x 8 = 371,2 v

MPPT 1 + MPPT 2 = 742,4 v

Изглежда, че вече сте надхвърлили абонамента, освен ако ограничението от 550v не е за MPPT

No voltage has been transferred. The operating voltage range is for a string, do not add the two strings. At the moment it is and it works very correctly.

ok, if 550v limit per string, then you can add extra 3 panels per string

MPPT Operating Voltage Range (V)125~550

MPPT 1 - 46.4 V x 11 = 510.4 v

MPPT 2 - 46.4 V x 11 = 510.4 v

6 minutes ago, Dieter said:

добре, ако ограничението е 550v на низ, тогава можете да добавите допълнителни 3 панела на низ

Обхват на работното напрежение на MPPT (V) 125~550

MPPT 1 - 46,4 V x 11 = 510,4 v

MPPT 2 - 46,4 V x 11 = 510,4 v

If the operating voltage range is ok, how does the power overshoot affect it?

Doubt it will overshoot more than 40 volt, which is 10% per panel

Where are you located? Are you in a country or climate where you are likely to experience -20 degrees Celsius? That is not typical weather for most places in South Africa. Most users on this forum would look at the 10 panels per string at 46.4V and be fairly comfortable that it's well within limits.

But for the over-Wattage, I'd be careful. Rather contact the manufacturer than rely on general opinion, as it may affect your warranty. I think at most maybe find an online solar output calculator where you can input your panel orientation data, azumuth, tilt, etc. to calculate your output for your location throughout the year, then try to keep within the Watt limit for the inverter based on that calculated output.

3 minutes ago, GreenFields said:

Къде се намирате? В държава или климат ли сте, където има вероятност да изпитате -20 градуса по Целзий? Това не е типично време за повечето места в Южна Африка. Повечето потребители в този форум биха погледнали 10-те панела на низ при 46,4 V и биха се успокоили, че е в границите.

Но за свръхмощността бих внимавал. По-скоро се свържете с производителя, отколкото да разчитате на общо мнение, тъй като това може да повлияе на гаранцията ви. Мисля, че най-много може би ще намерите онлайн калкулатор за слънчева мощност, където можете да въведете вашите данни за ориентация на панела, азумут, наклон и т.н., за да изчислите мощността си за вашето местоположение през цялата година, след което се опитайте да се придържате към лимита за ватове за инвертора въз основа на този изчислен изход.

I am in Bulgaria and the worst option for a low temperature is -20.

If the power of the inverter is (5 000 W. - max. input power (W)-6 500), and during the day it never exceeded 3 500 W, can solar panels be added to reach 5000 W?

23 minutes ago, kire said:

If the power of the inverter is (5 000 W. - max. input power (W)-6 500), and during the day it never exceeded 3 500 W, can solar panels be added to reach 5000 W?

Well that is what I was saying, the reality is that you cannot work in theoretical numbers only because there are always a bunch of losses. Since you aren't maxing out by a long shot (And as long as you see similar figured during the summer time) adding an additional 2 panels per string should be more than ok.

2 minutes ago, Psy said:

Това е, което казвах, реалността е, че не можете да работите само с теоретични числа, защото винаги има куп загуби. Тъй като не постигате максимален изход за дълго време (и докато виждате подобни цифри през лятото), добавянето на допълнителни 2 панела на низ трябва да е повече от добре.

your answer sounds very good