Multi RS Dual PV String voltages

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koossch asked Jul 28, '23

Multi RS Dual PV String voltages

Hello,

I have a question about the Multi RS Dual PV setup.
I've read both the specs and the manual but I cannot find the awnser.

https://www.victronenergy.com/upload/documents/Multi_RS_Solar/62787-Multi_RS_Solar-pdf-en.pdf

https://www.victronenergy.com/upload/documents/Datasheet-Multi-RS-Solar-Dual-Tracker-EN.pdf

When connecting 2 sets of PV Strings, do the need to have the same voltages?

For example: if I connect one string with 200 volt and a second string with 112 volt, will this be allowed?

Thank you in advance!

Multi RS

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Answer 1 · 2023-07-28T08:54:28Z

Guy Stewart (Victron Community Manager) answered · Jul 28, 2023 at 08:54 AM

Hi @Koossch,

Different string voltages are allowed for the dual tracker model Multi RS.

However the minimum start up voltage for the MPPT is 120V DC, so I think one of your strings is too low.

Always a good idea to run your design through https://mppt.victronenergy.com first

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Answer 2 · 2023-07-28T08:55:49Z

koossch answered · Jul 28, 2023 at 08:55 AM

@Guy Stewart (Victron Community Manager)

Amazing, thanks!!

Just to be thorough, is there any documentation on this being allowed?

Because I have the suspicious that this Dual string support is only in the new 2023 model, right? My model is HQ2232N2UX4 and I am not really sure if this is with or without the dual pv-support

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mvas commented · Jul 28, 2023 at 12:46 PM

If it is a DUAL MPPT unit then you can have two independent PV strings.
If it is a SINGLE MPPT unit then you can have one PV string.

Which model did you purchase?
A Single MPPT model or Dual MPPT model?

is there a "schematic diagram" on the front cover of your unit?

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koossch mvas commented · Jul 28, 2023 at 01:11 PM

I guess it's the Single MPPT model, but it does have 2 PV String connectors.
Having 'the exact same' product name and only this cover-print being the difference between the old and new model is rather confusing to be honest.

This is the front:

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multirs.jpeg (122.2 KiB)

mvas koossch commented · Jul 28, 2023 at 06:00 PM

Yes, sorry ... very confusing.
It is clearly a SINGLE MPPT per your schematic diagram.
You can use those two sets of input terminals as a "Combiner Box" ( ie parallel connections )
The DUAL MPPT unit would show two MPPT units in that little schematic diagram.

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Answer 3 · 2023-07-31T07:43:38Z

Guy Stewart (Victron Community Manager) answered · Jul 31, 2023 at 07:43 AM

Hi @Koossch and @mvas,

Apologies if my early post wasn't clear enough on this on this.

In mid-2023 the Multi RS was revised from a single MPPT tracker to a dual MPPT tracker model.

The single tracker model has this screen print schematic;

The dual tracker model has this screen print schematic;

The single tracker model is not able to efficiently operate with different voltages on the PV inputs.

The dual tracker model is able to accept and operate efficiently with different voltages on the PV inputs.

cleanshot-2023-07-31-at-173803.jpg (419.3 KiB)

cleanshot-2023-07-31-at-173749.jpg (454.1 KiB)

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GRIGORIU commented · Jul 31, 2023 at 06:54 PM

Can we find both products for buying or just the new one ?

And is there any catalog price difference between the two versions ?

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Guy Stewart (Victron Community Manager) ♦♦ GRIGORIU commented · Aug 01, 2023 at 04:29 AM

Hi @bgrigoriu

All new stock produced by Victron is the dual tracker model. We have stopped production of the single tracker model.

There may still be single tracker models available to purchase via Victron distributors, but very very few I would think. Most Multi RS were sold out during the transition.

There was no price change.

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energie-utechnik Guy Stewart (Victron Community Manager) ♦♦ commented · Aug 07, 2023 at 08:44 PM

Grüße an die technische Abteilung von Victron Energy. Vor einiger Zeit habe ich den Multi Rs Solar gekauft und installiert, aber es scheint, dass das neue Modell mit 2 Mppts ihn vollständig ersetzen wird. Was passiert nun mit der 1. Generation des Multi Rs Solar, wird er in Zukunft auch für eine 3-Phasen-Installation konfigurierbar sein oder handelt es sich quasi nur um ein Auslaufmodell der ersten Generation? Eigentlich bin ich von der neuen HF-Wechselrichterserie begeistert, würde mich aber über eine Rückmeldung sehr freuen, wäre aber auch enttäuscht, wenn er wie die anderen RS-Modelle keine neuen Funktionen wie 3Phasen bekäme. Mit freundlichen Grüßen Daniel Schroeder

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Answer 4 · 2023-07-31T07:46:42Z

koossch answered · Jul 31, 2023 at 07:46 AM

thank you Guy, I do understand now :)

thanks again!

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