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phips asked

MPPT Calculator bug with MPPT RS 450/100 or bug on my side?

Hello,

Is there a bug in the Online-Mppt-calculator, or do I have a bug in my brain?


Link to online MPPT-Calculator configuration is below.


1.String:

404.8 V at minimum temperature and Isc 14.15 A

2. String:
If I increase the number of strings using the drop-down menu, the online MPPT calculator can no longer find a suitable MPPT controller.
Although the 2nd string has exactly the same data as the first.

And according to the data sheet, the MPPT RS450/100 can handle max. 450 V and 18 A with each of the two trackers on the PV input side. Per tracker 7200 Wp.

Of course the MPPT RS450/100 is overloaded, the power of 404.8V x 14.15A = 5730 Wp is far from the maximum power of 7.2 kWp per tracker.


The Excel-Mppt-Calculator says that the “Solar module configuration” is accepted. And points out that the PV generator is more than 30 percent oversized. But, as already mentioned, this is not a problem.


Which configurator is right? Online or Excel.


I hope someone here knows more than I do.


Configuration Online-MPPT-Calculator:

https://mppt.victronenergy.com/#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

mppt calculatorrs 450
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2 Answers
snoobler avatar image
snoobler answered ·

Both are correct; however, they must be used correctly.

The online calculator is PER TRACKER. You can't just add additional strings to the same tracker as you would violate the Isc input limit. You have to add another tracker for each string. I have added a second identical to the one you entered, and it recommends both the /100 and /200 units.


https://mppt.victronenergy.com/#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

1 comment
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phips avatar image phips commented ·

Ok thank you very much, yes of course that makes sense. I totally overlooked the button, my mistake. Thank you very much!

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Alexandra avatar image
Alexandra answered ·

@Phips

The answer is one calculator has provision for oversizing and the other prefers not to.

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