Victron, Fronuis - ESS

Noted, I have done so

Please help, with the AC coupled I understand that only 1 output is utilised. How does one prevent overload of the system then? With the essetial and non essetial outputs I can understand. But if the grid tied is down due to it being dark how do we limit the current draw?
Also where can I get a schematic to connect a Victron multiplus 48v 5000 and a Fronuis primo 5.0kw GT ?

I’m not following you… sorry.

If you put the PV-inverter on AC-out-2, then it will indeed go down when the grid is out.

I don’t understand about limiting current draw when it is dark… what are you trying to do here?

There are numerous schematics on how to connect a Fronius in a Victron system. See Page 25 in the ESS manual for example.

With AC coupled, do you still utilise both outputs and spilt your board?

Are you saying that when the sun isn’t shining, the grid-tied inverter isn’t producing anything, and now you want to prevent an overload on your 5kVa Multi?

If that is what you are asking, my answer would be: Don’t use that much power when you can only rely on the Multi.

1 Like

Forgive me I am not making myself clear. Question is when setup as micro grid, do you uslilise the AC2 output for non essesials?

In a microgrid setup, there is no grid. You only have batteries, battery inverters, and the AC-coupled PV-inverters. AC-out-2 is permanently open (because there is no AC). So you will only use AC-out-1 in this case, and all your PV-inverters will be connected to AC-out-1.

If you mean a system that has grid available, but there are frequent outages that turn the system into a microgrid setup… then your loads on AC-out-2 cannot run when the grid is out.

Don’t count on the energy made by the PV-inverter as “extra” when designing the system. If you put a load on AC-out-1, ideally the Multi should be able to carry it on its own, at least for a few minutes.

Excellent, thank you for your explanation. -
If you mean a system that has grid available, but there are frequent outages that turn the system into a microgrid setup… then your loads on AC-out-2 cannot run when the grid is out.

This is what I was asking, so essencial load on AC1 and No essential load on AC 2

1 Like

So connected the Katbatt to the Multiplus2 but its not picking the battery up on auto. Will discuss with battery manufaturer in the morning.
Any advise, connected on VE bus

Would this not only happen when the battery is supported by Victron? If not, I believe people install the Smart Shunt product to get a SoC estimate?

Should be Ve.Can, not VE Bus sockets. Misspoke?

1 Like

Not mispoke, believe the installer said Ve bus. But I will check with him

The specs look similar to my Lithium Sa battery, do they give you the option like I did to connect ve.can

I’m pretty sure you either misunderstood, or the installer is confused. The only things you ever connect to a VE.Bus port, is another Victron Ve.Bus device. Third party stuff never connects to a VE.Bus port.

On the Cerbo there is however two CAN ports, one is marked VE.Can, and one is marked BMS-CAN.

The battery is NORMALLY connected to BMS-CAN, but there are cases where you will connect it to the VE.Can port. The difference is that the VE.Can port is normally reserved for Victron CAN-bus devices (like some of the MPPTs, the Multi-RS inverter/charger, or the MPPT RS), but in a system where the battery is the only CAN-bus device, you can connect it to the VE.Can port (and then you have to select the correct speed and profile in the Cerbo configuration).

Short answer: You need to use one of the CAN ports on the GX.

Thanks all for the valuable info, the installer has no experience with Victron and did infact cinnect to Ve bus so we will move forward with your great help.
Many thanks

1 Like

That is a bit sad, actually. You can’t just plug stuff into ports, and hope for the best? There is ample documentation on this, so it is not really excusable to do this kind of thing.

Up date, installer has established comm between Victron multi plus 2 GX and local produced battery pack ( Katbatt) from Port Elizabeth.


Does it send through all the correct charge parameters etc. if you go into the battery?

Aaaaand… it identifies as a Pylontech. It’s going to refuse to charge over 52.4V… which is where you already are…

They need to program their can-bus protocol to stop sending the letters PN in frame 0x359. Or better, switch to 0x35A for alarms.

1 Like

Yeah, which was my asking about the parameters, because the amps were zero.

Is the better solution not to leave out coms for now?