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Setting up 3 phase/2 parallel system - fixed


I am trying to set up 3 phase/2 parallel system based on 6 MP-II.

How to set the master and slave in each phase?


marekp asked
zain commented ·

1 Answer

Multiplus II 48/3000/35-32 en triphasé


Je suis en train actuellement de planifier la mise en place d'une installation solaire chez moi. La maison est en triphasé avec un abonnement 12Kva (pour éviter la question j'ai plusieurs appareil en triphasé obligatoire). Elle comportera aussi 5500W de panneau avec un RS 450/100 sur 2 strings et 9,6Kwh de batterie pylontech.

Je souhaite utiliser la sortie AC-out1 pour l'ensemble de la maison ( lumière, prise, électroménager..), et la sortie AC-out2 pour les gros consommateurs (géothermie, climatisation, plaque induction... )

Pouvez-vous me valider qu'une installation avec 3x Multiplus II 48/3000/35-32 permettra d'utiliser les 12Kva de mon abonnement au travers des Multiplus si nécessaire? je vois que le commutateur de transfert accepte 32A donc pour moi (32A*230V*3 Multiplus= 22Kw). Les plus gros pics vu sur 1 an de consommation montent à 10Kw.



demaos asked
demaos answered ·

3 Answers

3-phase system from 1-phase grid, with PV and ESS?


I am hoping someone can maybe assist me and check if my thinking is correct then.

I have a friend that wants to create a 3-phase system from a single phase grid connection.

We live in South Africa, so we struggle with load shedding (you can google what that means) which means he will need batteries for when the grid is off. He also want to have PV and push back into the grid. First question: Will it be possible for him to create the 3-phase system, have PV, have back up generator, have single phase grid supply, and have a battery storage system?

I understand that you can create the 3-phase system by using the master/slave configuration where the ACin goes into the inverter L1 and charges the batteries, and then L2 & L3 generates the second and third phase from the batteries. Will my friend be able to push back into the grid if he connects the PV system to the batteries with MPPTs?

Any help would greatly be appreciated.

Thank you.


martynhulsman asked
martynhulsman commented ·

2 Answers

3-Phase Multiplus-II ESS with Enphase - current sensor placement

I am planning a 3-Phase ESS with 3 MultiPlus-II, a Pylontech battery and would like to attach an AC coupled photovoltsic system with Enphase microinverters because of shading issues.

As long as the grid is available, the diagram below should work and Envoy would sense battery charging like another consuming device. Due to the built in backup capability of the MultiPlus-II it is not possible to place the grid-side current sensors the usual way between battery system and cutoff switch As soon as the grid there is a problem with the grid and MultiPlus-II cuts it off, the current sensor (light blue in the diagram) is cut off as well, so Envoy has no means to control the supported Solar energy.


My concern is that the two systems MultiPlus and Envoy could counteract and hinder each other doing their job.

Can this sensor be placed that it works with and without grit?
Could Envoy get the current sensor data directly from the three MultiPlus-II?
Is there a direct way to control Envoy or the Microinverters from MulitPlus-II or Cerbo?

(This is my first post in an energy community and im not firm with the termIndology epecially in English)

power4me asked
mr-manuel commented ·

6 Answers

3 phase single phase grid

Have a possible system to install

Client had a single phase AC grid supply

Is currently having to use a 3 phase generator for his 3 phase equipment means

Wanting to install a 3 phase Quattro set up With 3 phase fronuis SYMO to make make a micro grid

I know we can use the 3 phase generator for supplement the charging that the solar is falling short of

my question is can the single phase grid supply usable for supplementary charging with the 3 phase Quattro setup

Answering the question my self I would say no

Tho I think it may be usable if a single to 3 phase converter is used ???

anyone have any thoughts on this ?


mikeb asked
martynhulsman commented ·

2 Answers

2 x Multiplus 2 in 2-phase ESS configuration on 230V IT (3-Phase Delta Norway)


I know that 3-Phase Delta is not supported. But what about using 2 inverters in a 2-phase configuration with 120 degrees shift? The goal is to be able to feed in more than the max 16A on a single phase limitation we have here in Norway, and still be able to control everything from one single Cerbo. I have no need for a real 3-phase network on the back side of the Multis. Some single phase critical load on one of them is basically enough. The second Multi should only act as a grid-tie inverter on a different phase to even out the power between the phases.

I got this drawing from a Norwegian Victron distributor. I assume it comes from Victron. I understood that this was somehow tested, and it works. There were some instabilities in the voltage on large load variations between L1 and L3, but except from that it worked. This setup may work in an non-ESS environment, since you can disable the N-PE ground relay. In ESS-mode you cannot disable the relay, and you will short L2 and L3 to PE on the output. The picture also states that "Ground/PE must not be joined"


So what if we modify the above slightly to something like this:


It is possible that the phase rotation will be wrong on the second unit. I'm not sure, but if we assume this is ok, this would allow ESS and feedback. In case of a grid failure, it will look like this:


The internal relays will disconnect the inputs. The ground relay will kick in and join N and PE. Since we here have a common phase for N (the L3), this will not short out anything. It will create 2 separate single phase TN networks on the output. As long as you don't connect any load between the 2 inverters I cannot see that that is more problematic than running one single unit, which works fine.

Can anyone here confirm if above solution will work or not?


oet asked
gerardg answered ·

3 Answers

How does a 3 Phase quattro deal with a lost supply phase?

Hi . What happens if the mains supply to a 3 phase ( 3 x 5 KW) quattro loses a phase?

Does the whole system change onto battery, or will it continue charging off 2 phases and give a normal 3 phase output?

ralpht asked
sharpener commented ·

2 Answers

Three phase Multiplus II ESS system questions

I have read the three phase manual, but still some questions...

I have one MP II 48/5000 GX now on a grid connected ESS system but want to add some more, can the other phases be non GX as the GX will be master?

Preferably I want a total of 4 MP II's, the only issue I read about in the manual is the monitoring, so I assume its possible only monitoring is not accurate anymore. Will it also not be accurate when the AC gridmeter is monitoring? As this is monitoring in VRM the actual feeding or taking from grid

If I have 3 (or 4) MP II's connected one is the master. When sending commands to inverter to charge or discharge, do I send this to the master only or also to the slaves? I would prefer to control each phase with its own commands

banne asked
duivert commented ·

2 Answers

Three Phase off grid and single phase generator

Hi Victron team,

An installer/customer of DPA Solar is designing a 3 phase off grid system (possibly 3 x Quattro 8kVa) and has asked me if a single phase generator can be connected to AC IN on the master? I've read through the tutorial on VE SystemConfigurator and see that a similar example (3 phase gen with single phase shore power) requires 4 Multis.

Do we need 4 Quattros if the customer wants to keep his single phase gen? Or do we tell him to purchase a 3 phase gen?



David asked
Warwick Bruce Chapman commented ·

2 Answers

Victron Qauttro (x3) with Fronius 3phase (x1); Zero feed-in per phase not working.

We have installed a 3-phase system consisting of 3 x Victron 8 Kva's and Fronius Symo 20.0-3-M. The phase’s are not balanced by default as loads don't draw at same time. The problem is now that with one phase drawing higher loads than other two, the Fronius is throttling to the highest phase from loads, the two other phases (equivalent to the one or more loads being fed by Fronius via the Victron’s) then is being feed into the grid past the Victron energy meter.

How can we limit this feed into grid?


Tcp is enabled, PV inverter has been assigned, but at the TCP finds no IP address. Even if we enter the address in manually it does not change the feed into grid. All settings on Fronius match. Out of ideas to try and make this work.

jaqibar asked
Matthew Walsh commented ·

3 Answers

Fronius not producing ESS AC Coupled

We have a problem with our system for a client. The AC coupled Fronius inverters only supplies loads and doesn't charge the batteries. I've updated the firmware's on all Victron devices, batteries, and Fronius but still does the same.

I followed this guide as main setup: Victron Three phase setup
Then this guide after main guide: Victron Fronius setup
Then lastly the ESS setup with zero feed-in (4.3.11): Fronius Zero Feed-in

The system is up and running, all devices are detected and running as should, except the Fronius's are being throttled.

We first had the system off-grid (Client only later on decided he want's the grid as backup), the grid codes were set to Microgrid 50 and was only using Frequency shifting when throttling, when we tested it like this (About 3-4 days) the system operated 100% correctly, we switched off and left as site was still being established.
A month later the client pulled in the AC supply (from grid) cable and we went back to connect it, I noticed the system didn't throttle the PV when batteries are full because (obviously) the system stuck to 50Hz as it came in from the grid. I changed all grid codes to South Africa (NRS 097) and then I used the Fronius Zero Feed-in guide above to limit the Fronius inverters via TCP. This works and only feeds back minimally, but the PV throttles when loads drop, it shouldn't- it should charge batteries and then only throttle.

The system consists of:
Three phase setup
6x 15kVA Quattro's (2x per phase)
10x SolarMD SS4143 (143kWh)
4x Fronius Eco 27.0-3-S Inverters (1:1 rule was adhered to on DC side)

Any assistance would be greatly appreciated!

francois asked
Matthew Walsh answered ·

1 Answer

Online Training - 9.1 Three-phase and parallel system theory - Wrong schematic diagrams?

I just watched the Online Training video
9.1 Three-phase and parallel system theory
At time 3:14, when discussing "3 Phase" config, the schematic on the right is for "Parallel"
At time 6:49, when discussing "Parallel" config, the schematic on the right is for "3 Phase"

@Margreet Leeftink (Victron Energy Staff)

mvas asked
mvas edited ·

1 Answer

EM530 vs EM540

I'm planning a residential 3-phase ESS install using 3 x 5kva Multiplus II.

Looking at the meter requirements I purchased a EM530 assuming I needed to use CTs given I have a 3x100A supply (EM540 is max 65A). But, now I've looked at my expected max current I'm only going to have a max of 50-55A on any given phase, even with two 11kW car chargers and all appliances on the go.

So, the question is: Should I use the EM530 I have, but select a 60A CT, or is it really best to send back the EM530 and get the EM540?

Aside from the fact that the installation of the EM540 is simpler, the only difference seems to be "active power" accuracy and minimum current.

EM530 (assuming 5:60 CT):
- Accuracy: 0.5% (>3A), 1% (0.6-3A) (+ 0.5% from CTs so 1-1.5% overall?)
- Min current 0.6A

- Accuracy: 1% (>1A), 1.5% (0.5-1A)
- Min current: 0.25A

Looks like it's probably a good idea to switch to EM540 given this. Make sense or am I interpreting things incorrectly? Any thoughts?

daniel-feist asked
daniel-feist edited ·

1 Answer

Implementing ESS by changing Smart Meter to EM530 Grid Meter

We have a setup that includes 3 x Multiplus running in parallell on 3-phase and an AC coupled Fronius Symo. Grid-Feed-In is not permitted so for the past 12months+ it has been running with a Fronius Smart Meter.


One unintended consequence of this design is that it cannot run as an ESS, so the battery sits idle at 100% except when there is no-grid. When the grid drops the Fronius sits on the non-essential side and has been working happily.

We would like to convert the system to ESS so I have purchased a Carlo Gavazzi EM530 and plan to connect this to the Cerbo GX using an RS485 to USB cable.

The questions I have are:

  1. In the new ESS setup if I enable the zero feed-in will the GX do the same job of throttling the power output of the Fronius?
  2. Can it do this through the existing Ethernet connection between the Cerbo and the Fronius Datamanager?
  3. I assume the Fronius Smart Meter will be redundant?
  4. Without the Smart Meter can the system still talk to the Fronus SolarWeb portal?

Happy to answer questions, provide info. Q 1 & 2 are the essential ones.

Thanks so much in advance. I sometimes find it tricky answering these kind of questions from manuals and building confidence, so this kind of help is so useful.

tim-hickman asked

0 Answers

Maximum sets of three 15KVA MP2 in a three phase system?

I've seen the datasheet which says "up to 6 sets of three units can be parallel connected for a 75 kW / 90 kVA inverter and more than 1200 Amps charging capacity." but this obviously isn't specs for the 15kva.

Ideally, I'm looking to get more than the 180KVA of power possible with Quattro's for industrial off grid sites.

Any help would be appreciated!

Haydn Saunder asked
Matthias Lange - DE answered ·

2 Answers

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