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solar-samuel asked

Supplementary AC/DC charger options?

I have a 1.6kw RV solar setup with a Multiplus-II 120x2 and 810Ah of Lithium batteries that I use off-grid often. Most of the time the solar is more than sufficient, but I have a backup inverter generator that can do 3kw sustained load if it's cloudy or if I need to run air conditioning. I plug the generator into a 30A RVs shore power cable, which runs directly into the Multiplus AC in.

The system works well, but when I need to top off my batteries with the generator the 120A charger on the Multiplus + base loads ends up only drawing at most 2kw. I'd like to use that extra 1kw of generator capacity 1) to charge faster and 2) because I'm assuming it's more fuel efficient to run at closer to full load rather than half load. So I'm looking for a good option for approximately 80-ish amps of AC to DC charging, which I can hook up to my Lynx busbar. I'd like to stick with Victron products if possible, so that gives three options I can see:

  1. Skylla IP65 12/70
  2. Centaur Charger 12/80
  3. 3x Blue Smart IP22 12/30

The first two options seem to be very capable, but also very expensive. It feels like they have more design options than I need, and I'd rather not pay 800+ USD for these unless there is a very compelling reason to do so. I can find the 3x Blue Smart 12/30s for ~600 USD, which is still a lot, but at least better. They also seem to take up less space than the other two options. Honestly, if I'm spending almost 1000 USD it seems like it would be better to get a second Multiplus-II for the extra charger and inverter capacity, but sadly I don't think I have the space for it.

So I have questions:

  1. Does anyone have a recommendation as to which of these three options to use for this project? Pros/cons of these choices? Will they all integrate into my current system equally well?
  2. With whatever I end up using, would it be better plug it into the AC system currently on the trailer through the panel and therefore Multiplus, or run a dedicated supply cable from them directly to the second 20A AC outlet on the generator?
  3. What advantages am I gaining by spending 4-6 times more on a Victron-specific option here, as opposed to something like this: https://www.amazon.com/gp/product/B0CGTM9SQ6/
Multiplus-IIchargerbluesmart ip22Skylla
2 |3000

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0 Answers

Related Resources

MultiPlus-II Product page 

MultiPlus-II Manual

MultiPlus-II 230V Datasheet 

VE.Bus Error codes

Additional resources still need to be added for this topic


Blue Smart IP22 Product Page

Blue Smart IP22 230v datasheet

Blue Smart IP22 120v datasheet 

Blue Smart 230V online manual

Blue Smart 120v manual download


Victron Connect online manual

Did You Know? - use the blue smart as a power supply (video link)

History and Settings for Blue Smart Chargers in Victron Connect (video link)


Additional resources still need to be added for this topic

Skylla-IP65 product page (12v, 24v)

Skylla-i product page (24v)

Skylla-TG Charger product page (24v, 48v)

Skylla-TG GMDSS product page (24v)


Additional resources still need to be added for this topic