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jessard avatar image
jessard asked

Two Multiplus 2 Offgrid Systems Combined

Hi all,

I am looking for suggestions on the best way to combine TWO separate offgrid systems that both consist of a Multiplus 2 and their own separate battery banks. One Multiplus 2, let's call it MP-A has a significant solar input however the other, let's call it MP-B currently does not have any solar input so is just batteries feeding the Multiplus.

Now what I am trying to achieve is for the second system (MP-B) to receive AC from MP-A but only daily between 10am and 2pm to top up MP-B's batteries. I want this to happen automatically.

The systems are in separate buildings on a rural property 70m apart but there is already an electrical line from MP-A's output over to the building where MP-B is being installed . MP-B will supply a separate set of loads than MP-A does and the wish is for it to use it's own batteries as much as possible and as such I do not want this as a simple transfer switch arrangement at MP-B.

If I have MP-A's output fed into MP-B's input, use the ESS assistant on MP-B, and select a country code is there any chance that MP-B will fed back AC on MP-A and do damage?

Look forward to hearing your responses,

Jesse


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3 Answers
Michelle Konzack avatar image
Michelle Konzack answered ·

Your MP-A would need to be configured as it would be the GRID Provider and should also have the bigger batteries.


The second one should be a MultiPlus-II with feed-in capability.

And yes, this will work.


I have just done this with a Quattro 48/15000 as Master/Grid and as Slave/Client two EasySolar-II 24/1600 and one EasySolar-II 24/3000.


It is a small holiday park where you can rent small 12-20m² houses where each has its own Battery, EasySolar-II and some Solarpanels.


However, the whole thing is Off-the-Grid and they want to expand to up to 20 holiday homes.

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jessard avatar image
jessard answered ·

Hi and thanks Michelle,

Could you please explain further what exactly needs configuring at MP-A?


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Nir avatar image
Nir answered ·

Hello Jessard and Michelle,

I am looking to build a similar system, have you connected your system successfully?

My idea is similar, I want to build an off-grid grid where several off-grid sites can transfer energy from one to the other. I wish to start though with two sites, similar to your description.

As far as I see it, it should be pretty straight forward - the AC out of MP-A should be connected to the AC-in of MP-B. My hypothesis is that MP-B then will automatically start charging it's batteries (as it sees a grid in it's AC in) but I haven't tried it yet. There should be a limit (both electrical breaker and in software configuration) to the amount of power MP-B should take to protect the wires and to make sure it doesn't over consume from MP-A and thus fail it.

After that I imagine the automation of times of the day should be set by an assistant programmed through Victron-Configure. I have no experience in that yet, it only what I read but I hope to do so later this week.

Would be happy to hear if you have made any advancements on this.

Nir


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