frequency Image


ESS setup for fronius on AC IN side

Hi all. Is it necessary to add in the setup of the Assistant ESS. That I have a pv on ac out if the pv is on ac in ? I ask the question because I have a small problem.

System design 3 phase multi 48/5000/70 with fronius symo 8.3-2 ( 7.0 kw pv panels) on ac in side.

In the ESS Assistant I answered no acpv on out side.

During mid day the fronius is showing production on 8.2 kw even if the pv panels are 7.0 kw... can someone tell me where to look at ?


Can I set somehow to be 7.0?

mihaimicu asked
marekp answered ·

2 Answers

ESS stuck and blocking PV inverters with frequency shift

I had my system (6x Multiplus 5000, 26x Pylontech US2000B/C) working well for some time. Venus with version 2.73, i control the system via modbus to go on/off grid as needed (to have frequency shift and avoid feed-in i go off grid normally during the day). Yesterday i updated the 'US2000C' Master batteries to the latest firmware version as i had some battery alarms before.

Now as of today, i noticed that first batteries got fully charged, freqency shift regulated down the inverters (several SMA plus some micro inverters). But then .. as i used some energy, the frequency shift got 'stuck' at 52.7Hz and the battery started to discharge, despite full sunshine and much more solar power available then needed.
I switched to on-grid (which means the frequency shift must stop) and 'charge' mode briefly, and that seems to hae 'unstuck' the system. Battery then charged up correctly and all is good now.

I have updated the software of the venus now to 2.84, but the weird taste stays - why would ESS get stuck, stop the panel production and not charge batteries ?

I have a can sniffer running on the pylontech connection and log all data to a victoriametrics/grafana instance. The pylontech bms protocol does not report anything unusual.

Venus reports a max charge voltage of 53.2V, BUT when reaching full it overshoots and reports 53.4V ..

ESS output voltage (all loads and inverters are here) is stable 230V +/-2V on all phases.

Any idea what could trigger that lock-down ?


jacola asked
jacola commented ·

2 Answers

Victron coupled to Solaredge WR - Shutodown caused by frequency coupling


I have 6 Multiplus II 3000 connected to a Solaredge SE17K with frequency coupling.

Today we had several power grid outages and Victron went to Standalone Mode. After some minutes the Solaredge WR shut down and stopped producing.

One hour later (grid was back online since more than 40 minutes) the Solaredge went back online also. In the error log I found:

- AC-Frequenz zu hoch (Linie 1)

- AC-Frequenz zu hoch (Linie 2)

- AC-Frequenz zu hoch (Linie 3)

So it seems that there is an issue with frequency coupling. I am using the proposed setup from the victron handbook:

  1. The solar converter will start reducing its output power at 50.2Hz
  2. Output power will be reduced to a minimum when the frequency is 51.2Hz
  3. The converter will disconnect when the frequency is higher than 51.5Hz

Is this maybe not the best possible setup ?

Can I make this setup more failure resistent with other figures ?

Any suggestions ?



gawan asked
Paul B answered ·

1 Answer

High Frequency issue


I have a system with the following:

  • 3 x Quattro 48/8000/110-2x100
  • FRONIUS Eco 27.0-3-S
  • 3 x SmartSolar Charger VE.Can 150/70

The Fronius is connected on the Quattro output and now every time the grid falls, the Fronius runs for a couple of seconds then shuts down with error 105, high frequency. How do I rectify this?

nkonzo asked
Paul B answered ·

1 Answer

Another AC Out Question - BUT with a diagram!

Hi there,

Kindy please can I get some clarification, I have to integrate a lithium [Plylontech] system with an existing off-grid SLA system, there's a few challenges on the PV side but I'm largely confident I've solved them and so my main question is coupling the Growatt 5000ES off-grid inverter to the Multiplus-II,


Question: What's the most practical option here to connect the Growatt and Victron?,

My gut feel is connect it [Growatt] to the AC In and I'll run the Gen into the AC Input on the Growatt.

The other option I see is connecting the Growatt to the AC OUT (1 or 2) but I need clarification on how the Multiplus will handle grid forming with a fixed frequency/voltage from the off-grid Growatt.

Also if anyone has any tips on this install, I'm keen to hear them.

Any questions let me know,

Thanks in advance!

craig-l asked
craig-l commented ·

1 Answer

Multiplus Quattro AC frequency Hz variations

I've been trying to get to the bottom of why we have some flickering LED downlights in our house, especially those on dimmer switches. Dimmer switches are notoriousely sensitive to frequency variations.

I've been looking at my Multi's AC Output metrics from the VRM and I noticed that the frequency can sometimes drop as low at 48.34 Hz.

According the Multi's specs, there should be about a 1% variation on the 50 Hz output, which I calculate should only go down to around 49.50 Hz.

Can anyone tell me if this frequency variation that I am having is unusual for a Multi, or is that normal? I am wondering if this points to some type of fault?

This issue is occurring when we are running off the grid on ESS settings.

See screenshot below:


Nicholas Wessels asked
Alexandra commented ·

8 Answers

Multiplus 12\3000\120 output frequency 45hz

Just installed a multiplus 12v 3000w to 120AC inverter charger on a boat. I'm using the mk3-USB interface to adjust settings. The inverter output frequency is set to 60hz, but its showing only 45hz on the output. This happens when running off 12v 500ah house battery bank. Please help!



louise asked
sailalibi answered ·

4 Answers

Grid Support and Inverter Freq.Shifting


I have two problems on a 3-phase Victron Multiplus 5000/48/70-100 with battery pack (lead acid 24 x 2V / 1150 Ah each) operated as an island. Three SMA inverters and two Victron MPPT 150/60.

One is the gird supply: when the batteries are low (now visible due to less power production and more demand with a heat pump for heating the house)

The other is the freq.shifting for the inverters (SMA)

The grid supply assist doesn't work at all. The assistants are programmed (general flag and generator start-stop) but for some strange reason the grid doesn't start when batteries are low. I've upgraded the multiplus (all of them) to the latest firmware 487 and reprogrammed the system from blank. The same problem ...

The freq.shifting is even stranger, when the PV inverter Support assistant is programmed, the Multiplus continuously switches the inverters off and on (50 to 53 Hz). It starts working AFTER a heavy load (higher then the combined inverted power) ... after that it works normal

Both problems are a pain because or the batteries can be overcharged or the batteries can be completely discharged. Now I have to manually interfere all the time.

I've uploaded three VSC files (added the extension PDF otherwise I could not upload the files) for the multi's maybe someone can take a look and see if I'm doing something wrong.

SMA 1 = 3kw inverter = 3500 wP panels

SMA 2 = 3kw inverter = 3250 wP panels

SMA 3 = 3kw inverter = 3370 wP panels

Any help is appreciated !!!



Multi 1.vsc.pdf

Multi 2.vsc.pdf

Multi 3.vsc.pdf

jean-paul-1 asked
jean-paul-1 answered ·

1 Answer

Multiplus2 low AC output frequency.


While browsing through my recently installed 48/5000 Multiplus 2 (230V50hz) stats on VRM I noticed that the AC output frequency is low and out of spec.

The installation is a stand alone installation and the inverter supplies my home with power during grid power outages via a change over switch.

The output frequency is low from switch on with new and fully charged batteries, through varying loads.

Has anyone had a similar issue.

andrev asked
andrev commented ·

3 Answers

MyPV AC-Thor in off-grid system - settings?


the manual ( ) says that when using AC-Thor in an off-grid system frequency shifting (PV-inverter assistent) has to be activated at the Multi.

- Is this also necessary if only DC-coupled PV is used (no PV-inverter on AC-out)?

- what are the frequency settings in the "PV-inverter" assistent? Are the default-settings ok?

Best regards

e-box asked
Robert Bazalgette answered ·

5 Answers

Frequency shift- Quattro 48/15000

Good day .

Is there a way to determine why the inverter is Frequency Shifting ?

Is it possible to find out were the command comes from ?

I am running 3 x 48/15000 Qauttro , 56KWh Solar MD batteries and Solar Edge 27.5 Grid tie inverter.

The Qauttro's seems to shift the frequency and the solar edge starts throttling. Is there any way to determine what will make the Qauttro's start frequency shift ?


Johannes Cronje

johannes-cronje asked
Alexandra commented ·

2 Answers

Need some help defining "Frequencies" in ESS for SolarEdge PV inverter

I could use some help defining the disconnect frequencies in ESS for my PV inverter shown here; any help is appreciated!:


I live in the US, my inverter is 60Hz first off, these are default values I have not modified yet. My Inverter is a SolarEdge HD10000-H US. Active Power control via frequency is defined here in the manual, and can be set by the user:


It would seem that "P0 in my inverter relates to "The solar converter will start reducing its output power at XX Hz", I am guessing that P1 would be the next setting "Output power will be reduced to minimum when frequency is at XX Hz".. I am not sure what to enter for the final disconnect value though. The full manual on Power Control can be found here,

Can anyone provide any recommendation as to how I should configure this in ESS and which values should be selected for P0 and P1 in my inverter?

ee21 asked
Alexandra edited ·

2 Answers

Configure Multiplus 2 Frequency Shift with Sunny Boy 5KW (sma)

Hello everybody.

I installed actually one multiplus 2 5000 48v 70a with lifepo4 batteries (18s) and BMS JK.

I have one Sunny Boy 5kw installed in ACOUT with the multiplus 2. All the loads the multiplus 2 are in AC-OUT.

I have a question about the configuration frequency shift for the correct working multiplus 2 with Sunny boy.

The screen for configure Sunny boy frequency shift (default) is this:


What configuration I have to configure to multiplus 2 ESS?? This??


Thanks in advance.

Best Regards.

alfredogutierrez asked

0 Answers

Flicker and wild voltage and frequency variation of Quattro output when operating with generator


We are experiencing this same issue on multiple sites. Both with AC connected PV and sites with charge controllers.

Quattro 5kw off grid system. 50hz 230v

When the backup generator is operating, the output from the Quattro varies wildly and also it appears so does the load placed on the generator - to charge the batteries (from the VRM portal data)

This is backed up up by the display on the generator (Hyundai DHY6000) which shows frequency.

Frequency output from the quattro is so unstable it cases the Fronius PV inverter to cut out and also the washine machine on site to go into fault. Also voltage is all over the place, and all this causes lighting flicker too.

UPS function setting is off

I have tried lowering the shore power setting.

I have tried lowering the output voltage slightly on the Quattro. (output on the genny when unloaded is 230v)

Dynamic current limiter on or off makes no difference.

Accept wide frequency range is on.

I am assuming that the quattros inverter attempts to track the AC input frequency and doesnt do a great job of it.

If powerassist was disabled - would this prevent the inverter output from trying to track whats happening with the AC input ?

Any ideas?



Chris asked
Chris edited ·

3 Answers

AC Coupled Fronius Drops Power on Shifted Frequency Prematurely and More than Needed

Hi, I have an AC-coupled Fronius Symos on 3-phase configured Quattro inverters. I have enabled Frequency shifting in ESS assistant with pre-set configuration: starts at 51, lowest at 52.7, shuts down on 53Hz. I have set the Fronius on MG50 to enable this power reduction on shifted frequency. But lately I noticed that at 80% SOC, the frequency starts shifting up, and the batteries cannot be charged properly on AC PV power, although enough power to charge them fully is available. I also know that Fronius on MG50 starts power decrease at 51Hz and shuts down on 52Hz. What can I do to have better charging for my batteries on AC PV (start frequency shifting on 90% SOC and end with 53Hz on 100% SOC)?

Nazareth Kevorkian asked
Nazareth Kevorkian commented ·

2 Answers

61 Posts
58 Users

Topic Experts

0 Points