For some reason, the new Multi RS 6000 has a soft limiter of 5000watt grid feed in.
In the situation below, you can see that I have set my 3x Multi RS 6000 (in 3 phase) to feed back into the grid with 6000watts. I have also have a SolarEdge 3 phase PV inverter coupled on AC-in that is currently providing 8000watts of power (2666w per phase).
However, for some reason the total feed back into the grid is not able to go above 5000watts per phase, or about 20,6A. I have set the grid current limits to 25A, so there should be a lot more room.
The Multi RS units are only feeding about 2300W back into the grid, as the SolarEdge PV inverter is doing the rest.
I am not sure what is limiting the feed back into the grid. I have an external VM3P75CT energy meter directly to the grid. Firmware of the Multi RS is V1.20. Firmware of the cerbo is 3.60~53.
You did not read my post correctly, the Multi RS is only feeding back about 2300watt at the moment as the SolarEdge PV inverter is doing the rest. No matter what setting I choose, there seems to be a soft limiter to 5000watt at the grid. My SolarEdge PV is even delivering 9300watt at the moment, but the grid feed in remains the same:
Battery is able to provide 855A (both DCL and CCL), so that shouldn not be the issue. (it’s a 136kWh battery bank).
My AC-in current limit is set to 25A, but it makes no difference if I set it to 35A or higher.
There is no peak-shaving setting in the Multi RS via Victron Connect, in remote console there is also no peak shaving setting in ESS (like there is with Multiplusses).
We are getting to a point were my solar PV inverter is providing the full 15kW were as the Multi RS is hardly doing anything, but I cannot figure out were that 20,6A limit is coming from.
Before the Multi RS, I had 3x Multiplus 5000 and I was able to feed back into the grid over 25A (my grid fuse is 25A so I wasn’t able to go any higher, but the system could have easily)
Another update: when I disable external current sensor in Victron Connect, the Multi RS is infact feeding back more that the total amount.
As a test, I have set the Multi RS L1 to -2300W while my PV inverter is feeding back -3300W into the grid, and the result is that right now, the current is going over 20,6A:
So this proves to me that there is something wrong with how the Multi RS is handling the external grid current meter. If it goes above 20,6A, the feed in is limited. When I disable the external current meter, the total current can go above 20,6A.
One last time: raised the feed in to -2600w and the total current on L1 goes to 25A as it should.
However the setpoint for L2 and L3 are still on -6000W, but with the external current sensor enabled.
And as soon as I enable the external current sensor on L1 again, the total feed in drops back to 5000w or 20,6A.
So to me, this seems like a bug in the firmware.
Maybe I can add something here:
I’m experiencing the same issue, but my system setup is a bit different. I have a single-phase grid connection with a 40A limit. I’ve set the grid current limit to 40A, and I’ve also noticed that when feeding back to the grid, the AC-in power is limited to -5000W.
Since @vaursechs mentioned that this problem doesn’t occur when DESS is enabled, I tried to control the Multi RS in the same way that DESS does. Using dbus-spy, I checked all registers of any services related to the following:
/Ess/InverterPowerSetpoint
/Ess/UseInverterPowerSetpoint
/Ess/AcPowerSetpoint
/Settings/CGwacs/AcPowerSetpoint
/Settings/CGwacs/MaxFeedInPower
And also the registers related to feed-in limits, AC current limits, etc.
Through dbus-spy, I couldn’t find a single register that limits feed-in to a value around 5 kW or 22 A.
I tried setting all ESS setpoints and inverter setpoints to -10000, but it still limits to -5000W.
Even when I capture VE.Can messages using candump and decode all the traffic between the Cerbo and the Multi RS, I see the correct AC current limit values. I haven’t seen anything suspicious or anything that would explain the 5 kW limit.
Please note that I only got more than 5000w with DESS enabled AND my PV inverter also feeding back into the grid. So the Multi RS did not feed over 5000w into the grid on its own.
That said, I believe the limit is softcoded into the Multi itself and is not send via the cerbo. Which is why this problem does not exist with Multiplus 2
[CORRECTION] Yesterday I noticed that, even with DESS, the system did NOT feed back more than 5000W into the grid, even though there was enough PV power available.
I’ve been running a single MultiRS with 2 strings of 6x440Wp solarpanel on its mppt trackers alongside a 13kWp 3-phase SolarEdge inverter for about a month now.
The MultiRS was managed from NodeRed by setting the ESS power Setpoint.
I started out without the VM-3P75CT gridmeter, and through ESS power Setpoint I was able to fully control the power flow at the MultiRS AC-in connection.
After I installed and enabled the 3 phase VM-3P75CT grid meter for the (single) MultiRS I saw a soft limit on the full 3 phase power flow at the grid connection similar to the one described by others in this thread. Disabling the VM-3P75CT grid meter in the MultiRS settings allowed me to control the MultiRS without ever seeing the ‘soft limit’.
By now having expanded my system to 3xMultiRS I haven’t noticed this anymore, and run with the VM-3P75CT fully enabled in the MultiRS settings.
