3 phase Multi RS (D)ESS

Hi everyone,

Just wanted to show my newly installed ESS consisting of:

  • 3-phase Multi-RS setup
  • Cerbo GX
  • Lynx Power in
  • Lynx Distributor (125A fuses)
  • 3 x 5,12kWh ZYC Simpo 5000 batteries
  • VM-3P75CT energy meter
  • Ruuvi Temperature meter

Combined this with my existing Enphase PV system.

The most important reason to choose Victron is to become more resilient against power outages. In the Netherlands they are very rare. However unbalanced energy market and evenly unbalanced political situations could mean a different situation in the future. Another reason is obviously to make better use of your own solar power.

First I was considering a MultPlus system. However the placement of the system would give the risk of noise transmission within the house. And buzzing sound during the night wouldn’t be appreciated by my family. Coincidently the Multi RS was granted certification for grid code in the Netherlands which would allow those to be used as well and give us a more quiet and silent option.

No regrets. It runs smoothly and the configuration was a breeze with the new bluetooth setup in Connect. As well as using the ZYC batteries that install automatically after connecting to the Cerbo. Plus get firmware updates through VRM.

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Great setup!
I’m curious—do you have any AC-coupled solar connected to the AC-OUT of your system?

Yep. Perhaps you can see it on the pictures.

I have an enphase system which installed on AC out.

3 phase q-relay via a circuit breaker on the output side of the bypass transfer switch.
Incoming PV Energy is measured by the 3 phase Victron energymeter.

This will make sure the PV remains functional during maintenance.

Thanks for the details!
How much solar power do you have installed on the AC-OUT? And when your system is both discharging the battery and generating at maximum solar output, what is the maximum (Negative) AC-IN current?

Also, which specific model of bypass switch are you using? Can it be switched under load, and does it switch quickly enough to keep the loads powered without interruption?

Thanks!

No worries,

So I have about 4400 Wp divided over 3 phases coming from the PV’s So that is not too bad.
Since I only have 3 x 5 kWh batteries (ATM) I limited my (dis)charge rate at 15,3 kWh ~ 66,5A and my feed in into the grid is limited at 15,9 kWh ~ 69A (Max of the 3 RS units)

Regarding the transfer switch I have one from the offgridcentrum in the Netherlands.

However there are obviously plenty of other options for example from Hager.
The one I have is switchable under load and as long as you do not stay too long in the “0” position there is no interruption.

Thanks! I was wondering if it’s possible to feed in more than 23A at 230V per Multi RS, because I have a single-phase system with 4 kWp of solar connected to the AC-OUT.

I’m experiencing some strange behavior:
When solar production is at its maximum and there are no loads (so AC-OUT reads -4 kW), and I’m also discharging the battery, the system limits the discharge power. The AC input current maxes out at -21 to -23A, meaning the battery isn’t discharging at its full 5 kW potential. My AC current limit is set to 40A, but for some reason, it restricts feeding in to a maximum of 23A. However, when charging the battery and running high loads on AC-OUT, it does pull the full 40A from the grid.

From my understanding, your system doesn’t have this issue because your solar is devided over tree units. Thanks again for the information! Just posting this explanation in case anyone else encounters the same problem.

That behavior is perfectly normal I think

If you have only one unit 23A is indeed the maxmimum you could invert. (6000 VA is around 5300W = 23 A)

When importing you are obviously also using energy without your RS having to work. So indeed you can get higher numbers there up till the maximum of your Grid capacity.

The system will only perform up till the maximum of the “weakest link”

Since I have 3 units my performance is also times 3. Hence the 69A.

Multiplus units are able to be switched parallel so you can increase performance like that. However Multi RS cannot (yet?) be placed in parallel. So afraid ATM this is the max you can get out of your system.

Yes, that is indeed the maximum from the inverter from the battery. But in my case, I am also feeding in excess solar from the AC-OUT. When discharging the battery while simultaneously feeding in solar from the AC-OUT, the system isn’t actually inverting that solar power because it’s AC-coupled.

Since the Multi RS has a 50A transfer switch, I would expect it to simply pass through the 4 kW of AC-coupled solar and additionally invert 5,200W from the battery. This should result in a total AC-IN of 4,000W + 5,200W = 9,200W, which equals 40A feeding into the grid.

I think (and someone from Victron needs to confirm) that the 50A you are talking about is only for PowerAssist incoming current.

That is at least how I understand the specification sheet. But again I’m not the expert.

I understand your reasoning, and that could very well be the case. I would expect that it shouldn’t matter since the transfer switch physically connects the output to the input, but again, you might be right.

Thanks for your help!

Your welcome.

One little thought from my side.
I’m not sure what your energy provider thinks about fully discharging your batteries whilst they more then have their hands full on trying to cope with all that solar excess…

Yes, I’m aware that this is not a very common situation in practice. I trade with the dynamic energy tariffs in the Netherlands, so discharging usually won’t happen when there is a lot of solar production. I was simply testing whether it would theoretically be possible if I were to have high solar production later in the evening with higher prices.

UPDATE: I experienced issues where the system would completely shut down at random moments. (And I mean really shut down… power out in the whole house even though the grid was up)

I’ve been closely working with the Victron crew to get it sorted. Firstly we thought it had to do with the firmware however it turned out to be something else.

Looking at the VE-Can communications in Remote Console we discovered a great amount of bus-errors. So basically what happened was that the 3 RS units were not able to communicate with each other. Consequently resulting in the shutdown.

SOLUTION: I replaced UTP cable used to connect the energy meter to the Cerbo (VE-Can) and it is smooth sailing ever since.

Wanted to share this so if you experience similar behavior… remember to look at your VE-Can communications. It will potentially save you a lot of hassle and annoyance.

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Jou systeem lijkt wel heel erg op hoe ik dacht het bij mij op te gaan zetten. Enige verschil is dat mijn Enphase PV systeem ongeveer 6kW kan leveren.
Nadat bij mij de warmtepomp installatie is afgerond staat deze stap wellicht toch wel sneller op de planning dan ik eerst dacht. Wellicht zal ik dan graag jou laatste update / ervaringen horen.

Hi Arjen,

Leuk om te horen. En je mag altijd ff aankloppen. Die 6kw blijft zelfs voor 1 fase binnen de 1:1 regel dus dat gaat helemaal goed komen.

Alleen zal je waarschijnlijk wel uitkomen op 4 accu’s. In principe heb je per 1,5kWp ongeveer 100ah nodig aan batterij (48V).

Nu met het mooie weer van de afgelopen dagen goed kunnen ervaren wat het systeem doet als de batterij vol is. Het BMS van ZYC regelt het allemaal keurig. Ook de hoofdschakelaar omgegooid en je ziet meteen de frequentie shift en hoe de enphase erop reageert.

Al met al erg tevreden

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