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Pack Batteries 20kwh 48v. 2XMultiplus II or 1x multiplus 5000

Good afternoon.

At the moment I own 2 packs of 10kwh in lithium batteries connected in parallel to 48v.

I was thinking of putting a multiplus II, or a multiplus 5000. We both would be connected in parallel to grid.

Given that the multiplus II is recent would be preferable, for what I intend?


Meanwhile, the idea of putting 2 multiplus in parallel (each destined for each pack of 10kwh) came up to better take advantage of the 20kwh. Would it be better idea to opt for a multiplus 5000?

I think I gain in power to inject in my house with the multiplus II (2400wx2), against 4000w of the multiplus 5000). On the other hand, if one fails, I always have the other.

I intend to use solar energy essentially from the Mppt side for efficiency. For my configuration of 2x20kwh (32cells), with 2 multiplus II would it have to have 2 Mppt?

Thank you for a quick response from someone who can help me decide.

Thank you

MultiPlus Quattro Inverter Chargerparallelmultiplus ii
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4 Answers
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wkirby answered ·

It is a tough decision, although in my own mind I think I would prefer the simple option of just 1x MultiPlus 5000.
Only advantage with 2x MultiPlus II is a little bit of extra power (do you need this) and maybe some redundancy. If one MultiPlus fails and there is too much load for the other one, then it will also shut down.

I would always have 1x battery pack, for you 1x 20KWh, splitting battery packs is difficult to balance the charge on each one. Also you can have different voltage drift on the negative legs and then blow up ports on VE.Bus.
Even if you have 6x MultiPlus' always have 1x battery bank.

MPPT, you did not say anything about your solar array, so it's not easy to say. But, you will only have 1x battry bank ;) So you will only really need 1x MPPT unless you have more PV than it can use.

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dam answered ·

Thank you for the answer WKirby.

I'm sorry for my english.

Yes the power difference is not much.

Will there be more charging?

Why did you opt for a MultiPlus 5000 instead of 2 multiplus II? Robustness? price? Functions? Fewer configuration issues?

I have up to more than 20kwh about to be assembled. There are 32 cells of 220Ah lipo4 in 2 kits of 16 cells with 2 BMS of 300A each to work with the 48v of the multiplus. I had thought to connect 2 packs dea16 in parallel to give the 48v, since the cells have 3.2v. Do you find it difficult to balance the load and tension like this?


Mppt is 60A to 160vdc. I have thought of 8 panels with 275w with approximately 38voc and 9.45A each panel. I'll make parallels of 4 + 4 or 3 + 3 + 3.

I intend to continue using my fronius ig30 with 8 panels which I already have installed.

I'll be right my thinking, or it would be preferable to get another mppt or u. Mppt more powerful?

In case the option passes through.

Thank you.

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wkirby answered ·

Hello.
Your English is fine, I can understand you. :)

Charging power is the same with 2x MultiPlus II (2x 35A) or 1x MultiPlus 5000 (1x 70A).

1x MultiPlus 5000 = Simple setup, fewer configuration issues. Price, there is not really much difference.

Did you construct your battery bank already? By far the best way would be to have 2x 3.2V cells in parallel, then x16 of those in series. You will only need 1x BMS with this method.
2x 48V banks (1 cell x16 in series) is OK because you have 2x BMS, but it is more complicated.

Solar MPPT: Are you using a Victron one? Other MPPT is OK, but Victron one can communicate with it's friends much more easily. I don't know of a 160V charge controller?
If you have 8 panels, how will you make 3 + 3 + 3 (9)? Do you have another panel to make 9? This will be the only real option with a 150V (160V?) charge controller with a 48V system.
4 + 4 (8) is going to be too close to high voltage even for 160V controller. If it gets cold then the Voltage can go higher than 160V and it will damage the MPPT. You would need a 250V MPPT controller to use this option safely.
2 + 2 + 2+ 2 (8) is too low voltage for a 48V system to charge properly.
60A MPPT can make about 3KW on a 48V system, so is a very good match for your PV.

Keep the Fronius, this is a good machine and there are options for integrating it into the system.

Like I said before, you will only need get another MPPT if you have no option for 9 panels. Another brand of MPPT will work, but will not have the options that a Victron one will offer if you want to use CCGX or VRM in the future. If you buy a new MPPT, then go for as much power as you can afford (100A), then you can add more panels easily in the future if you want to do that.

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dam avatar image
dam answered ·

Obrigado WKirbyby


Sim, a carga é a mesma com 2x MultiPlus II (2x 35A) ou 1x MultiPlus 5000 (1x 70A), mas 2 multiplus II poderiam injetar mais 800W no máximo. Minha dúvida, neste momento, também teria a ver com a robustez do multiplus II. Seria igual a 5000. Eu entendi que o multi II teria mais funções porque é mais recente. Verdade?


Um amigo que me ajudará, construiu um banco de 16 células de 220ah em série para um multiplus II, com um BMS de 300A e um MPPT makekyblue de 60A a 160Vdc. Decidi seguir os mesmos passos, mas com 32 células de 220ah, já que tenho mais consumos em casa. A questão que temos no momento é saber até que ponto os 2 BMS de 300A podem "manipular a mensagem", já que os pacotes em paralelo terão mais de 400v para circular. Estou vendo as coisas bem?

Soluções?

Eu comprei um mpous makekyblue de 60A para 160Vdc que eu já tenho comigo. Além da facilidade de comunicação entre o multiplus e o CCGX Victron que falou, teria outras vantagens em mudar de mppt?

Eu tenho 8 painéis que eu queria dedicar ao makekyblue a 48V

4 + 4 (8), se você acha que pode estar muito perto da alta voltagem (aqui as temperaturas mínimas de inverno podem chegar a menos de zero graus). Você pode exceder 160V com meus painéis de 275w? Eu posso reduzir para 3 + 3, mas é claro que eu cobro menos!


Em vez do velho Fronius como é no AC, posso conseguir um menino SMA Sunny a um bom preço de 3800 ou 4000Tl. Saber que ele pode ser regulado pelo acoplamento vitron emac seria um valor agregado, ou seria melhor deixar as frentes como está em AC? Menos complexo?


Uma coisa que me ocorreu, em vez de obter um segundo MPPT como indicado, seria deixar o multiplus II carregar com AC em excesso. Neste caso, 2 multiplus II, 2 bancos de

Haveria 2 bancos de baterias.

- por um lado, um BMS + um multiplus II + MPPT para carregar um pacote de 16;

- por outro lado, um BMS + um multiplus II, um banco de 16 células para carregar como excesso dos frônios.


Sim, o VRM é atraente. Eu queria ter, a ideia era economizar algum dinheiro. Como eu tenho uma framboesa, sei que também posso desenvolver algo no nível do monitoramento, mas não é a mesma coisa!

Mais uma vez obrigado WKirbyby

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