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ESS System not feeding in grid :-(

I got a 5k MultiPlus II running with a set of 10kWh BYD LiFePo4 batteries (with their own BYD BMS) en two DC-connected MPPT's with a total PV-capacity of around 2400Wp and a Cerbo "running things"..
The Cerbo is updated to the latest firmware (automagically through the internet). The MultiPlus II is on firmware 2623470 and runs the ESS-assistant more or less with the default values of the German gridcode with internal NS protection.
The only thing I didn't let the assistant change, is the type of battery (because of the BYD-specific settings for Absorption and Float).
This time of year I have quite a surplus of PV-energy so I started experimenting with ESS (Optimized with BatteryLife).
For some reason the system is NOT feeding the surplus of PV back to the grid :-(
Only if I set the grid setpoint to a negative value, the system starts to feed back the PV to the grid at the height I set the negative grid setpoint to....
Otherwise, the BMS (I think) switches off the MPPT's so they don't deliver any PV anymore :-(
For some reason it does that when the BMS says (at VRM and in Remote Console) that the batteries are at 99% instead of 100%. I have no idea why it does that but this doesn't bother me too much ;-).
I set the minimum SOC (unless grid fails) at 95% otherwise apparently the system thinks it should feed the loads from the grid, even when there's still enough PV to do that and even enough to charge the batteries.
So not the actual surplus of PV energy is fed into the grid, but the value set with the negative grid setpoint...
So when there's a cloud before the sun and the batteries are still above the minimum SOC (unless grid fails) then the system feeds the grid from the batteries if the PV drops below the value set in the negative grid setpoint....
I probably have some setting "wrong" to get this result, but I can't seem to think of what could be wrong....
If someone has suggestions..... they are more then welcome.

spithost asked
lifeingalicia answered ·

9 Answers

ESS nutzt PV nicht effizient


ich habe ein Problem mit einem Victron ESS System.

3x Multiplus II 3000
Cerbo GX
2x Pylontech 3000C
vorerst 1x MPPT 150/45
vorerst 2x Module 400W Vertex S in Reihe

Ich weiß, dass das viel zu wenig Generatorleistung ist. Wird noch auf ca. 6kWp erweitert.

Nun zu meinem Problem.

Ich habe das System als 3-phasiges ESS eingerichtet. Netzparallel über die ACin Anschlüsse. An ACout 1 und ACout 2 hängt bisher nichts.

Die Pylontechs sind über CAN angeschlossen, der MPPT über VEdirect.

Es läuft auch soweit sehr gut.

Jedoch stört mich das Verhalten bei (wegen zu wenig PV noch recht häufig) Erreichen der SOCmin Schwelle.

Wenn die Pylontechs die SOCmin Schwelle erreichen, hört das ESS völlig richtig auf die Batterie zu entladen.

Es hört dann jedoch völlig auf das Haus mit PV-Strom zu versorgen und fängt an mit 100% der zur Verfügung stehenden PV-Leistung die Batterie zu laden.

Wenn die Batterie dann wieder SOCmin+3% erreicht hat, schaltet das ESS wieder auf das Haus und entlädt die Batterie teilweise sehr schnell wieder um dann bei SOCmin wieder abzuschalten.

Das kann doch so nicht effizient sein. So muss doch quasi ein großer Teil des gerade recht geringen PV-Ertrages erst unnötig verlustbehaftet in die Batterie rein um kurz danach wieder entladen zu werden.

Es müsste doch eigentlich so sein, dass bei SOCmin der Entladevorgang der Batterie stoppt, jedoch die erneute Aufladung der Batterie nur aus PV-Überschuss gemacht wird. Alles was man an PV-Leistung direkt verbrauchen kann, müsste doch viel effizienter direkt ins Haus gehen.

Nur an der zu kleinen PV kann es meiner Meinung nach nicht liegen, weil im Winter ja auch eine große PV tagelang wenig Ertrag bringen könnte.

BatteryLife ist aktiviert. Ich habe es aber auch schon ohne versucht. Das ändert nichts.

Habe ich vielleicht noch eine andere Einstellung übersehen?

Viele Grüße

ojack asked
ojack commented ·

3 Answers

ET112 energy meter / Cerbo GX. baud rate

I have a ET112 energy meter, a RS485 to USB (serial) cable and a cerbo GX. What is the serial baud rate (9600 ??, 115200 ??) the cerbo uses over the USB serial connections ?.

CONTEXT: the ET112 and the Cerbo are remote, and I am building my own device to connect the USB serial on the ET112 side to the USB serial on the cerbo side.

I know about the zigbee adaptors, but do not want to use those.

Thanks you

pabou38 asked
lifeingalicia answered ·

1 Answer

Can my ESS produce reactive power to the grid?

I have a ESS with two Quattro and solar power. I have feed in excess power enabled.

This has been operating for two full months and the house meter has

  1. 941 kWh Total Active energy consumed (from grid)
  2. 600 kWh Total Actve enery fed (to the grid)
  3. 40 kVARh Total reactive energy consumed
  4. 330 kVARh Total reactive energy fed

I can understand some consumption of reactive power due to some pump motors we have, but not the export of reactive power.

Any help on this is much appreciated.

macevedo asked
fatbloke commented ·

1 Answer

AC Load not always showing correct values

Ever since upgrading the Multiplus II to 492 and Venus OS to 2.82 (coming from 2.74), I have noticed that the AC loads are not always showing the correct values.

I often see AC load on phase 1 going to 0W.

It looks like it is cause by delays in reading out consumption values from either the Multiplus or the Grid meter. My battery cells are not well matches, so the BMS will start to constantly decrease and then again increase max charge current. So the Multiplus is constantly dropping and increasing the charge power quite a lot. Seems that, when u sudden increase or decrease occurs, it takes some time for the GX device to correctly recalculate the AC load.

Not sure if this is impacting anything other than the displayed statistics.

Anyone have any idea why this might be happening?

I have made a gif showing the issue. Note that power consumption is actually stable, so the AC load values are definitely incorrect.


timd93 asked
timd93 commented ·

2 Answers

configuration ess

Hello, I have an easysolar 2 gx, smart meter, 12 kwh canbus battery, fronius primo 3kw.

I can't get the system to work as I would like.

I can only inject into the network the fronius which is positioned on ac in.

All loads are on ac out 1.

With ESS I have large production losses because when the battery is at 100% the mppt charger is switched off and the load is always powered by the fronius.

I tried ignore ac input disabling ess but I don't like how it works because it drains the battery when I have production from the fronius.

What I would like is to prioritize from the mppt with the power surplus from the battery or battery charge to 100%.

example :

2500w fronius production,

1500w mppt production,

1000w loads,

battery 100%

what happens is that the mppt is at 0w and the fronius feeds the 1000w of the load instead I would like the fronius to continue injecting 2500w into the grid and the 1000w of the loads came from the mppt.

I hope I have explained ... I can make almost all the necessary changes apart from injecting mppt into the grid ...

Do you have any advice?

lucadea1985 asked
sharpener answered ·

5 Answers

ESS importing and exporting with full battery

Background_IMG_1947.MOV (1).mp4Under_load_IMG_1946.MOV.mp4

Pets ESS settings.TXT

Multiplus 2 48/5000/70

Cerbo GX c/w touch


4 x Pylontech us3000c

System only set up and running for 2 days.

All seems stable when running background loads but when asked to do some work >1Kw, there is draw from the grid and also some exporting ! see video

Could someone explain and check my settings please.

pet asked
matt1309 answered ·

1 Answer

RCD placement in Multi-II ESS

Hi - on a 3x MPII 5000 ESS system, Victron requests a RCD Type A on AC-Out-1. We have realized that with a 4phase RCD 300mA. Does this RCD need to sit immediately at the AC out or can there be a distribution block in-between?

Background: we have a thick cable running back from the installation in the garage to the house, so the AC Out RCD is in line with the then following house connection. However, between AC Out and RCD in the garage, we have a block connecting AC out with solar inverter AC, wallbox (with separate 30mA RCD), some plugs (with separate 30mA RCD).

Any trouble/disadvantage with such an arrangement?

krouink asked
matt1309 edited ·

1 Answer

Whats the best way to see activity on L2 using ESS

I'm running a DC coupled ESS system (mode 1). My panel is split phase not 3 phase. I have essential loads on AC out 1 Connected to L1 in the breaker panel (120v). I am not currently using AC out 2 for non essential loads they are still in the breaker panel. Aside from moving those loads to AC out 2, What alternative do I have to to monitor L2 in VRM and have ESS take it into consideration? I do have an EM24 That is not hooked up to the system. But if I use it it supersedes the current monitoring of the multiplus plus, that is my understanding. Any suggestions?

duswami asked
Alexandra commented ·

4 Answers

Solar chargers don't work under ESS

Good day,

Two solar chargers Smart MPPT 150/70-Tr and Smart MPPT 250/70-Tr don't charge the batteries under ESS mode. On VRM the system shows this:


I have set the system to not sell any PV excess to grid. However if I set the system to sell the excess, controllers do start to charge and export PV excess to grid:


Moreover, if we disconnect the VE.Direct cable from both controllers to Venus GX, they do charge battery bank but system doesn't run under ESS:


Any clue of what could be wrong on configuration? I need to set the system up properly for ESS and I have compared all parameters with other systems I have installed that seems to run properly on ESS.

Thank you in advance for your help.

dgmar-ni asked
dgmar-ni answered ·

6 Answers

ESS VE Config query when using current sensor instead of grid meter.

Hi All,

Quick question on VE Config setting.

Set Up - Parallel grid tied AC ESS, Multiplus II, Venus OS (pi4), 30m external Current Sensor connected directly to the Multi, existing PV with grid tied 'dumb' inverter using victron AC current sensor, (NO power meters).

Question1 - In VE Configure General Tab - 'External current sensor connected' - should this be ticked ? -

Question2 - Now in the ESS settings on the VRM portal after loading the assistants what do we select under 'Control without grid meter' - On or Off ? We have no grid meter as we are using the current sensor, however its a parallel system so the house loads are not installed on the AC out as stated in the ESS manual ?

Thanks for taking the time to read this and any help you are able to offer.

jetstram61 asked
jetstram61 answered ·

1 Answer

Multiplus compact version, smartsolar and ESS

Hi, this is what I would like to achieve, see picture also with schematics.

Daytime (green arrows):

- Run load on solar - power from MPPT through inverter to load

- Charge battery on the leftover solar current (split solar charge current to inverter and battery, is the split configurable in some way?)

Nighttime (orange arrow):

- Run load from battery through inverter

- If battery SOC is too low use grid power (light blue arrow from grid through Multiplus)

Equipment I already have:

- Multiplus Compact - mfd. 2013

- Smartsolar 150/60 MPPT - mfd. 2021

- Solarcells and battery

The question is can I create this configuration with the multiplus compact I have if I purchase the Cerbo GX controller? I also read something about gen2 processor on multis needed and some firmware version limitiations. But I could not get the grips of it. So I try to ask here:

1. what should I check with my multi compact to be sure I get this to work as I plan.

2. And can this be done with the cerbo GX and a multi compact?



norrback asked
alexcj commented ·

4 Answers

Slow battery charging

I work in a hospital in Mulanje (Malawi). We have recently connected 6 Quattro (6x15kW) with 6 Fronius Symo (6x15kW) AC-coupled. We have 6 battery banks (29 batteries in total). Each bank has a BMV and battery capacity of 500Ah (5x100Ah). 1 bank is different with 400Ah (4x100Ah). It is in Malawi not allowed to feed back to the grid. The system is running pretty good but we are dealing with the next issue.

When there is not enough solarpower to provide the load of the hospital and to charge the batteries the system is not using the grid to charge the batteries. For example we have a powercut and the batteries will be discharged until 8% and the powercut is over it will not start charging the batteries from the grid to the minimum SOC set in the ESS. Also not when i enable the setting 'keep battery charged'. Only when there is enough solarpower it will use the batteries to store the load. what can i do to change this? See pictures for more info. Thanks in advance.



mmh asked
marekp edited ·

3 Answers

High frequency issue when grid fails

I work in a hospital in Mulanje (Malawi). We have recently connected 6 Quattro (6x15kW) with 6 Fronius Symo (6x15kW) AC-coupled. We have 6 battery banks (29 batteries in total). Each bank has a BMV and battery capacity of 500Ah (5x100Ah). 1 bank is different with 400Ah (4x100Ah). It is in Malawi not allowed to feed back to the grid. The system is running pretty good but we are dealing with one issue.

When we have low voltage (<180v) the Victron will switch from grid to the battery. Then the frequency goes up briefly to 52,9Hz or 53,1Hz. The next thing is that the Fronius-inverters shut down because of high frequency (error state 105). We have the correct county-settings in the Fronius (MG50). I know that it happens when there is no place to store the energy. But it happens also when the battery is at 40% and the hospital load is 40-60kW. The Fronius-inverters try to start up again and again but gives error until the grid-voltage is good enough for the Victron to go back to the grid. Normally it happens, between 11-2, when the sun is very strong and we need the Fronius-inverters to charge the batteries for the night. In the ESS is the possibility to change the frequency range but the advice to leave it like it is. I added some pictures for clarification. What can we do to solve this issue?

Thanks in advance, Gerwin Habermehl




mmh asked
mmh commented ·

1 Answer

On-Grid PV Inverter als Generator für Multiplus II ?


ich möchte ein AC-ESS mit einem Multiplus II 5000, Pylontech-Akkus und dem EM24 realisieren. Als PV Anlage habe ich noch eine Anlage von 2010 im "Überschussmodus".

Soweit, so gut. Leider habe ich aber keine Autarkie-Möglichkeit, sollte das öffentliche Netz mal down sein. Ich habe dann lediglich die Akku-Ladung da sich mein Wechselrichter (Mastervolt XS4300) nicht mit dem Multiplus AC-koppeln lässt.

Nun aber folgender Gedanke: am Multiplus stelle ich AC In1 auf "Generator" und schließe dort den PV-Wechselrichter an. Dieser synct mit dem Multiplus und lädt dadurch primär den Akku.

Start/Stop des PV-Inverters ließe sich über den Relaiskontakt schalten, wenn der Akku voll ist, wird ein Relais geschaltet und der Wechselrichter vom Multiplus getrennt, wird eine bestimmte Akkuladung unterschritten, dann wird der Wechselrichter hinzugeschaltet, synchronisiert und lädt dann den Akku.

Das wäre vielleicht nicht die eleganteste Lösung, sie soll ja aber auch nur im Desasterfall funktionieren.

Wäre das prinzipiell möglich oder habe ich einen Denkfehler?
Besten Dank!

chrisu asked
chrisu answered ·

9 Answers

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