Multi RS Solar and solar panel incompability

DIY
,
1

Hello everyone,

I just bought a Multi Rs Solar double tracker, but now i am unsure of the solar panels I chose for it. The panels I bought were on discount, cheap and high quality so I bought too quickly when I should have taken more time to think regarding the compability with the Multi rs.

Anyway the panels have been delivered so there is no turning back

The panels are 500w, 45 voc,13.2A imp and 14.05A isc. 7 panels in series on each mppt (east-west configuration).

So there is no issue regarding the Voc, i am under the specs. However Multi Rs mppts do not go beyond 12A imp and also can support up to 16A isc

I know the mppt will clipp at 12A so they will not be able to squeeze all the panels power, but it is not what bother me the most as majority of the time the panel will output less than 12A anyway.

What bother me is the very low ISC value of the mppt, which is 16A. The panel under normal STC irradiance produces max 14.05A isc, so it is below 16A, good. The issue is irradiance can go higher than STC under certain conditions that are met not so rarely (clouds for exemple). This is why there is a safety factor of isc x 1.25 in most european countries

So 14.05 x 1.25 = 17.5A, which is higher than the 16A of the mppt.

So i am scared that if a short circuit happens at the panel level during a very high irradiance moment, it will destroy the Multi RS.

What do you think? Do you think the current clipping and ISC thing will reduce the life of my Multi RS?

As a solution for this , i am thinking about buying a separated mppt 450/100 and not using the mppts of the Multi Rs, but i am waiting for your opinion on this topic..

Sorry for the long post and thank you for reading all this post

2

The MPPT is never going to draw more than 12A from the panels. As long as your panel polarity is correct and system voltage (on cold days) and edge of cloud is <450V, you’re fine.

3

If you run it through the mppt calculator and it saysbits ok. Then it is ok.
I got something started to make it use the multi rs however I don’t know what panels you have so edit those for each tracker - there is a basic database.

4

Thank you for your responses.

The mppt calculator says the panel is compatible.

However , it seems that the data for the multi rs 6000 is not accurate. For exemple, it still shows 80A max charging, while the double tracker multi rs has 100A charging (single tracker version had 80A).

So i cannot be assured that other metrics are accurate (single tracker version had 20A isc for exemple)

5

Its 6kW total 3kW per tracker. See the datasheet.

100A total from ac and pv combined.

In anycase your panels will be ok on the RS, you do need to size your switchgear according to regulations.