Victron Multiplus 2 help

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Cobra_Phil

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I am in the process of planning out my solar installation which will consists of 10 330w solar panels, and a SMA inverter. The SMA inverter is not by my choice, so I don't have an option to use something else.I want the ability to add a DIY powerwall in the near future, but don't want to spend the money on a SMA sunny island. I think the Victron Multiplus-II will allow me to add the battery to the system, I just need help figuring out what I need between the victron and the battery. It will bea 48v, 8kWh Jehu circuit board design with aliexpress BMS. It appears the victron just outputs absorption and float voltages. I am thinking I just need to add a CC CV DC-DC converter to charge the battery.But I don't fully understand how the victron, charger, and battery are hooked up? Should the victron battery terminals feed the battery charger? Or should the battery charger feed come from another power source? Because I wouldn't think the victron would be able to read the battery voltage through the charger circuit. If it does come from another source, then I think there would be conflictbetween the victron trying to charge the battery and the CC CV DC-DC converter trying to charge the battery?
Thanks for the help.



image_iiblyn.jpg
 
Phil,
You do not need a separate charger.

have a good read on the manual of your MultiPlus, Victron has a wide adjustable charging voltage span.
https://www.victronenergy.com/inver...61.1756875065.1567343226-910056610.1549745117

BMS, cheap chinese: should somehow have relais control under/overvoltage + over/under temp to control the MultiPlus
Batrium, Rec-bms, and SIMPbms have can integration with the GX gateway of Victron, and is a sophisticated control of charge/discharge

Perhaps check out the ESS blog of Victron, and yes silly buying Victron Lithium blocks, if you can build your own
https://www.victronenergy.com/live/ess:design-installation-manual

Carel
 
Glad to hear that you too are thinking about going down this path aswell.

I am looking at pretty much the same setup, the Multiplus 2 should already incorporate the inverter/charger function as perprevious post.

One thing that got me stuck was understanding the AC OUT1 and AC OUT2 interfaces, basically AC OUT1 is for critical loads and AC OUT2 is for high demand loads that wont be fully covered by the battery pack in the event of a grid outage.

In my case, i amthinking that AC OUT 2 will power (Electric hot water, AC units and Oven) and when the grid is connected the battery will be 'assisting' load when the any of the loads are active.

Would be great to see how you progress in this setup!
 
Me2, Looking for a similar "adding hybrid" to a 3phase solar edge PV system.
Our house is 3-phase and the Victron MultiPlus II operate in single phase. It is compatible, yet there will be some limitations I've not yet completely wrapped my head around.

If that was not the case, Victron is an easy pic with REC Bms or Batrium.
 
Read the manual,
it can be linked in master slave mode,
and with that you can put 3 in series to have a 3-phase system,
or
have them in parallel as well to up power.

Carel
 
OP: You can connect your panels to the multiplus in three different places.

If you can get rid of the PV inverter altogether, you can connect them to the battery via a Victron MPPT controller. This is the most efficient way as there is no DC-> AC -> DC conversion going on. The PV charges the batteries direct via DC.

dewki said:
Me2, Looking for a similar "adding hybrid" to a 3phase solar edge PV system.
Our house is 3-phase and the Victron MultiPlus II operate in single phase. It is compatible, yet there will be some limitations I've not yet completely wrapped my head around.

If that was not the case, Victron is an easy pic with REC Bms or Batrium.
Click to expand...

For a single-phase Multiplus II in a 3 phase system (Australia and Germany) all you do is enable PHASE COMPENSATION.

Its tricky to explain how this works, but essentially in Australia we get billed for the NET power - regardless of phase.

So if you produce all your solar power on Phase 1, but your usage at any given time is say on phase 2 and 3 the following scenario plays out:

EXPORTING phase 1
IMPORTING phase 2
IMPORTING phase 3

In Australia and Germany the power company bills you for the NET of the three.. they dont bill each phase individually.

Sooooo - your multiplus can be connected to Phase 1, and with phase compensation it will EXPORT an amount that makes the NET of all three phases as close to 0 as possible.

intra said:
Glad to hear that you too are thinking about going down this path aswell.

I am looking at pretty much the same setup, the Multiplus 2 should already incorporate the inverter/charger function as perprevious post.

One thing that got me stuck was understanding the AC OUT1 and AC OUT2 interfaces, basically AC OUT1 is for critical loads and AC OUT2 is for high demand loads that wont be fully covered by the battery pack in the event of a grid outage.

In my case, i amthinking that AC OUT 2 will power (Electric hot water, AC units and Oven) and when the grid is connected the battery will be 'assisting' load when the any of the loads are active.

Would be great to see how you progress in this setup!
Click to expand...

You don't need to use either of them BTW.. you can put all your loads on the input side. If you're on grid, most of the installations would have AC1 and AC2 outputs left disconnected. The multiplus will produce enough power from the batteries to make the import of power from the grid as close to zero as it can. (it uses either a clamp meter or an external meter to do this EM24 is the model (for three phase anyway)
 
slimf said:
You don't need to use either of them BTW.. you can put all your loads on the input side. If you're on grid, most of the installations would have AC1 and AC2 outputs left disconnected. The multiplus will produce enough power from the batteries to make the import of power from the grid as close to zero as it can. (it uses either a clamp meter or an external meter to do this EM24 is the model (for three phase anyway)
Click to expand...

Interesting!

I have a Fronius Primo with SmartMeter, i'm led to believe that Victron has quite a good interfacing methodology so hopefully we can use the smart meter from Fronius (I still need to research this bit).

In regards to the AC1 and AC2 outputs, does this not put you into a situation that when the grid goes out thatheavy appliances will drain the batteries faster instead of keeping critical loads on for longer?

I don't think i'll ever be attempting to power the A/C during outages , but would like the lights to be on in the house for the duration.
 
If the grid goes out with your loads on the input, it all goes down..
Not a problem for me.

You could put a few critical loads on the multiplus outputs I suppose.. if you really need that grid independence.
 
slimf said:
You don't need to use either of them BTW.. you can put all your loads on the input side. If you're on grid, most of the installations would have AC1 and AC2 outputs left disconnected. The multiplus will produce enough power from the batteries to make the import of power from the grid as close to zero as it can. (it uses either a clamp meter or an external meter to do this EM24 is the model (for three phase anyway)
Click to expand...

I was giving this a little more thought lastnight.

How does this work as there are four possible connection points on the Victron

[img=640x480]https://www.victronenergy.com/uploa...ultiPlus-II 48V 5kVA (connections1).png[/img]

1. DC IN (Battery) + and -
2. AC IN (Grid) A, N & L
3. AC 1 (Critical Load) A, N & L
4. AC 2 (Non Critical Load) A, N & L

Logically the battery would connect to number 1 and grid to connection number 2.

How can you leave AC1 and AC2 disconnected , energy from the battery will go nowhere.
 
Yes, AC In is bi directional. The Multiplus will send battery power out of this port to loads, and even export to the grid if you want it to.
 
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