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njordan avatar image
njordan asked

Dynamic-CutOff settings in a 3phase system (ESS)

A rather short question that keeps me wake this night after configuring my 3 phase multiplus II system + pylontechs.

I did everything as requested, prepare the generic setting of the 3 phase system. then VEmulticonfig of each inverter by itself. for the first one (i guess the master, on phase1) i had to set the cut-off voltages......as written in the victron/pylontech page. But when starting to configure the phase2 device (that was "naked" at that point of starting).....there was the question of sustain voltage,....but not CUT OFF voltage in the assistant anymore, the same for the phase 3 device. tried several times, but its not asked in the process at all. the same for restart voltage....

so i'm uncertain if this is all OK as its only asked for the master.....(???) can someone please confirm its normal and not required/asked for each inverter. Kind REgards Norbert

ess settings
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4 Answers
Alexandra avatar image
Alexandra answered ·

@njordan

Did you go through the ve bus system configurator to open to configure each inverter through there?

You can save the config from and upload the master onto each inverter through there.

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njordan avatar image
njordan answered ·

I started with the quick config to setup the 3phase system and link the inverters (3) to its phases. then i uploaded to the inverters as a starting point.

Then i did config each and every multiplus by itself and always checking/changing the parameters + add the assistant for ESS. in some videos it was shown that if you upload to all of them the assistent would be lost, not transferred.

Maybe i did something wrong, but i at least tried according to the success videos on youtube.

Also, something observed and strange - when sending to each and every inverter individually i never had any question about the grid code password. but when i once tried to send to all of them in one step i was asked for a grid code password. i have an idea what it is, but i was not sure from the question if they ask to set a password or if they requested to make a new one.....

All three inverters are flashed with recent 508 firmware, so from reading there should be no password set, if i got it right.

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Alexandra avatar image Alexandra ♦ commented ·

@njordan

You need to go over to Victron professional and get some free training before you go any further

You are missing some important steps.

The grid code is settable once without a password. After that to change it or parameters related to it. You need a password. A firmware update wipes out all settings except that one.

For a three phase or other complex system, you configure each inverter from the Ve Bus System Configurator.

And uploading the saved config file from there transfers all assistants. Or at least it has in my experience.

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njordan avatar image
njordan answered ·

@Alexandra thanks for your feedback and the advice. Even if it does not look like, I spent quite some time before i started to configure. its just some parts like this grid code password. some state in forums that its cleared out when firmware is flashed. Anyhow the password is available so if ever asked i could simply enter. i have no intend to change grid parameters that are set for good reasons.


I cannot check it right now.....but maybe you can tell: in VenusGX the DVCC setting for "MAximum charge current" is ment for all 3 phases together.....is 35Amps means arround ~1,8kW.

As i have AC-in coupled PVs that seemed today to not clear out to Zero-Feedin. bit i was above 2kW production, so i now guess it was because of this limit set to the old 35 Amps....


1707855681336.png
Pic shows a situation where it should have ~zero per phase, but its not the case for L3. but with the limit of 35amps i guess it will not do so. cant check as its night right now....


Also regarding this "suddenly request to enter the grid code password" i have an idea why it happened. as none was set, it was fine without request to upload per inverter, BUT as soon as i said to copy the MASTERs config to all of them its a different task that takes a config from a certian inverter and this forces to enter the grid code password.....i simply was confused and love to understand the process behind. Cheers, Norbert




1707855681336.png (8.0 KiB)
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Alexandra avatar image Alexandra ♦ commented ·
@njordan

To program ESS assistant you have to set a grid code.

Possibly then you have different grid code set on each inverter then.

If they are not all programmed the same, they will not perform the same in ESS.

With AC PV usually they produce equally on all phases so if phase 1 &2 are consuming all the power but 3 loads are lower it may tend to feedback on that phase.

Then you have phase compensation in ESS. And your grid set point. This also affects how the phases work.

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njordan avatar image
njordan answered ·

Thanks again, trust me - i spent about 3 hours just for the config, checking again and again. i did set everyone by itself from zero. so grid code is for sure correct. but i will go down in the basement today and have another session :-) just to be sure.


In my case its little different i do a "individual phase - compensation" so each inverter looks at its phase. the reason behind is that i should not send any energy outside...with a 3phase compensation it would put some phase(s) negative and compensate with positve......


Do you know about my previous question, if the 35 Amps max charge current in DVCC is ment for all 3 phases....because that would clarify the strange result i had with zero-feed enabled.


Kind Regards

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