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AC supplement "pass-through"?

I have a question about “pass-through” on my two 24/3000 Multiplus(s)

I haven’t delved into this feature too much, and what I have read/seen, its still a vague concept to me.

My setup at home is 5kW of Solar PVs(LG), 3 Victron MPPT’s (150/100 & 250/100), feeding into a series of Lynx busbars to two Multiplus 24/3000, running in split phase, to a separate sub panel, charging and powered from 60 kWh of LFP batteries (SOK).

I have been slowly adding more and more loads to the subpanel, and it virtually powers anything substantial in my home. My weekly consumption is about 150 kWh on the subpanel, with about 40 kWh still being power from the grid on my main panel. I have not added any high current loads such as the Dryer or Stove (yet), but routinely run my pool pump and air conditioner off the subpanel (solar/battery)

I understand the concept that, if I was in a boat or trailer, connected to “shore” power, and the shore power was limited, to say 20 or 30 amps, and if I tried to run loads that exceeded the capacity of the shore power, the Multiplus(s) would ’supplement’ the power requirement from the battery bank. (Correct?)

What about the opposite? If I ran my stove off my subpanel (~5000W), one leg drawing about 3000W, and my Multiplus was already supply 1000W to the ’normal’ loads, so now it needs to supply 4000W, would it draw power from the grid to make up the difference? (The 24/3000 Multiplus will nominally supply only 2400W).

Both Multiplus(s) are connected to AC power from the main panel, but told to “ignore” AC until my batteries fall to less than 20% SOC.

Graydon asked
Alexandra answered ·

1 Answer

ESS Multiplus-2 AC-Coupling: Inverter on AC-Out 2?

Is it possible to connect a grid-inverter to AC-Out 2 on the Multiplus?

My idea is to save the EM24 compared to connenct the inverter on AC-In.
(Multi is measuring the currents but kick the inverter out if grid lost)

puitl asked
haagsemark commented ·

1 Answer

Daily use of external AC switch with Multiplus II

Is there any problem for Multiplus if I switch AC input on/off with regular external 250V switch instead of Multiplus internal control while Multiplus is running? That would be for daily use.

pekkaj asked
nickdb answered ·

1 Answer

AC Coupling offgrid with zero injection

Hi, I have an off grid installation with a DC Coupling via Victron Smart Solar, Victron Multiplus and OPZS batteries. I want expand it via AC Coupling, but until April there aren't Fronius Primo on market, for this reason I bought a Solax inverter.

Multiplus communicates to Solax increasing frequency, but I'm afraid this increase may damage the appliances or may lead to a malfunction of these.

I have a Smart Meter Chint DDSU666-D 80A 1Ph, it's an export limiting meter.

I want install it between the AC Out Multiplus and the house loads, so that it regulates the Solax according to the loads and no energy is sent to the Multiplus.

There are any problem with this configuration?

Maybe I could set the Multiplus to very low frequencies such as 50.01 instead of 50.20 to start the Solax output reduction, 50.03 instead of 52.70 to minimize and 50.05 instead of 53Hz to stop the Solax?

If I don't configure the Solax it will be regulated by the Smart Meter regardless of the frequency sent by the Multiplus, right?

What will happen when the Multiplus detects that the Solax has not stopped?

With my DC Coupling system, now I can charge overnight consume and batteries stay on float almost all day.

I attach a simple diagram.



kyuketsuki asked
kyuketsuki answered ·

5 Answers

AC-couple Victron Quattro systems


Can the Victron Quattro be used as a Grid Following device? In other words, can we AC-couple Victron Quattro systems with one system being Grid Forming, and the other Grid following?

power-consultant asked
shaneyake answered ·

1 Answer

is it possible to connect an SMA 9 kW 3 fase connected to AC1 of 3 x Quattro 8000

We want to build an 3 fase 48 Volt backup system with 3 x 8000 W Quattro's installed. on the AC1 output we want to connect our exsisting 3 fase SMA 9000W ac grid tie inverter. As we have to deal with the 1:1 power we are wondering if this is still withing these limits as the SMA is 9kW but deverted to 3 fases and not capable to deliver 9kW on 1 fase or am I wrong in this?

Any advice is welcome.

thank you


kvdbrom asked
Mike Dorsett answered ·

1 Answer

Multiplus-II + couplage AC Fronius Primo


nous avons installe un systeme avec Multiplus-II , cerbo-s et Fronius primo en AC OUT 1.

Tout le monde apparait sur le l'ecran deporte. Les parametres ESS sont bien ceux repris dans la documentation.

Pourtant nous avons du loupe un detail car le Fronius delivre 40 W, preque rien n'est pris sur la grid, toute la puissane fournie a la charge est extraite du banc de batteries.

Si nous retirons les bouchons des ports bus du fronius, il produit alors ce qu'on attend du champ solaire et la batterie se charge, mais le Fronius a disparu de l'ecran du cerbo (et sans doute du VE.bus).

J'en deduit que c'est le multiplus qui restreint le fronius. Mais je ne vois pas sur base de quel parametre(s)? J'attendrais qu'il produise plus et charge les batteries...

Ni pourquoi rien n'est pris de la Grid? Peut-etre est-ce le comportement normal jusqu'a atteindre le niveau minimal de charge de la batterie programmee?

Apres environ 5 demi journees sans succes, je m'arrache les cheveux et desespere un peu :(

toute piste d'idee serait un bonheur ;)



jeanscotch asked
Thierry Cortassa (Victron Energy Staff) answered ·

1 Answer

Victron Multi + Fronius Primo Hybrid system!


I am having the Fronius AC Coupled at Multi's AC Out1, and trying to set all for Grid Feed-in limited to a given value.

Should it be the Fronius discovered on the Modbus TCP device list? for me is not there. Scanning not helps.


zsolt asked
zsolt answered ·

2 Answers

Quattro 48V-8000VA Off Grid - additional AC supplies connect

I plan to add further supplier sources to my of grid System: 3x Quattro 48V-8000VA with Pylontech Batteries 40kWh behind. For continuous feed I would like to integrate a SkyWind Micro - Wind mill 1kWmax connected to the 52Hz off grid environment.

The FuSystems SkyWind is able to drop the AC power if no loads are connected.

The power is provided by a 60Hz AC connection in the micro grid while dumping the power into a heat sink when no loads are connected. In between a 60V DC to AC conversion is done.

Question: Does the Quattro AC output provides an adequate (grid like) stable frequency and 1-phase voltage to the SkyWind AC-Converter/Controler (needed to simulate an on-grid / without feed-in situation)?

Is the Quattro’s AC frequency strong enough, concerning the consumer sided behaviour based on active loads or no power consumption situation to indicate the heat sink or AC power provisioning ?

Does the Quattro provide preventions to consume itself the AC power on the micro grid side?

It seems a simlar control as been established with “Fronius PV Inverters” on the AC consumption/ micro grid side, which in fact has to be configured in a special setup.

khwf asked
cristimv answered ·

2 Answers

Phoenix Inverters with AC-coupled PV

I have an off-grid system with PVs and Phoenix inverters C 12/2000 working in parallel. I would like to add a grid-tie inverter to the AC output of the Phoenix inverters to increase power. What I have learned so for from previous discussions is that this should work, Phoenix inverter is the same as MultiPlus just without AC input for the grid connection and can charge the batteries? Is this right? If yes, then the 1:1 rule applies.

So this setup will work only with grid-tie inverters that support frequency shifting. How can you know if a certain inverter has this feature? I can get Fuji FU-SUN 3kW inverter or FUJI Microinverter 2kW at great prices, but I don't know if they support frequency shifting.

tuky asked
tuky answered ·

1 Answer

Groupe sans neutre sur Multiplus 2

J'effectue une installation solaire hors réseau, Multiplus 2 48/5000, RS Solar 450/100, batteries Pylontech US5000. Nous avons prévus un groupe électrogène de secours, je viens de constater que ce groupe (SDMO Kohler 6000 AVR) ne possède pas de neutre (les deux plots alimentent en 230), est-ce que le Multiplus 2 va accepter ces caractéristiques? S'il n'accepte pas, est-ce que relier un des deux plots à la terre pourrait résoudre la question? Il faudrait également que la protection différentielle de la maison fonctionne en mode groupe.

En vous remerciant,
Très cordialement.


jacques-v asked
jacques-v answered ·

6 Answers

Multiplus 2 ESS, Fronius Symo on AC-Out 1 and grid-lost: Symo turns off for 2 minutes


In my ESS with 3x MP2 and an Fronius Symo on AC-Out 1 the Symo turns of for about 2 minutes if the grid is lost.

After the 2 minutes it restart´s and run´s on the micro-grid of the Multi´s.

Why is that?
I assumed that the Symo is running without a brake in this case...

puitl asked
puitl answered ·

3 Answers

AC coupling on Multiplus II with micro Inverter

Hi Guys,

I am googling for long time now and maybe I just use the wrong key words or dont understand what I am reading, so I try to ask here. Maybe someone can help.

We have an Offgrid PV System based on Multiplus II, 3kWp Solar panels (DC coupled with Victron MPPT) and 10kWh battery from pylontech.

The setup works very good, but we want to increase the photovoltaik power.

The setup is installed in an old farm and the orientation towards the sun is not optimal, so we think about installing PV modules all around the area to get good energy all over the day...

Now the question:

It would be ideal if I could just take micro inverter for every PV module and couple them via AC coupling to the system. I know the 1:1 rules and so on. But I dont find micro inverters which support frequency shifting as SolarEdge, ABB or Fronius do.

Is there a working and tested combination of Multiplus II together with microinverters which supports frequency shift for this setup?

Which microinverters can be used here?

I am very thankfull for ideas or help so

Thanks an best regards


richard-offgrid asked
Michelle Konzack answered ·

1 Answer

Off-grid PV Inverter support on AC IN - respond to frequency changes

In all of my searching, I can only find configuration options to modify the behavior of Multis/Quattros by changing the frequency on the AC Output. But I'm still a novice in the Victron world, so maybe I've overlooked something?

What I'd like to achieve is change battery charge/discharge parameters based on the frequency of AC Input. As far as I can see, this isn't possible, but I'd appreciate being corrected if I'm mistaken!

My goal is to use Multi to:

  • keep SoC > XX% (or keep a minimum DC Voltage)
  • if frequency > XX, charge batteries (ideally, current increases with frequency)
  • if frequency < XX, discharge batteries (via PowerAssist or Ignore AC?)

The purpose of this is to interact with an existing off-grid system in a supportive way. Grid-tied inverters will curtail their output in response to rising frequency. To avoid "wasting" that energy, I'd like my Multis to store power in the battery, until the excess condition is gone, then give this energy back again until the batteries approach empty.

I'd prefer to use an Assistant or Virtual Switch over something like Node Red, but I don't see the functionality there. Am I missing something?

randyoo asked
randyoo edited ·

0 Answers

Setting up an AC coupled system with string inverter Aurora 6 kW with Multiplus or Quattro


I have a customer which already has a grid tied system using 27 modules of 230W and 1 string inverter 6 kW Aurora model PVI-6000-OUTD-US.

I understand that CCGX has built in a FRONIUS module for AC coupled systems and I have the doubt for other models that can be compatible and if there is an specific software product from Victron to do it.


dgmar-ni asked
rgerber commented ·

2 Answers

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