DVCC How are charge limits applied?

DIY
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Hi folks,
I just found something else I don’t know… And although I am 100% confident that there is much more that I don’t know, I don’t know, I would like to pin down this one thing, for now, if anyone can help.

This came up in another thread, and I realised I didn’t have a good answer, in fact no answer, once I considered it properly.
It would have been off topic, and or thread hijacking, to ask this specific question there.

I use DVCC on one of my systems to manage charge current, the specifics are not important, there is only one energy source, AC in, and I only use DVCC because it allows me to set a charge current, easily and dynamically, not because anything needs sharing or distributing.
It works just fine in that limited application, although I am sure using it like that will garner some comment.

However my question is this…
On my other system,

Multiplus 48/5000,
SmartSolar on VE Direct port.
BYD 13.8 kW B-Box pro, Can connected.
CCGX.

With DVCC enabled, forced on by the BYD battery in this case, how would setting a charge current limit affect my two energy sources, AC In, a generator and a DC coupled SmartSolar charger.

Assuming that there was both AC and solar available and I applied a charge current limit using DVCC, would the two chargers back out by the same current / percentage, or would one of them be backed out first, favouring the other, solar presumably, were that to be case.

I can probably test this, if there isn’t a clear answer, but I am hoping that there will be an answer, and some rational to help me understand why it is the way it is… whatever that may be.

The issue with testing is scope, a single test may give me an answer in specific circumstances but I wouldn’t be sure that it always applied!

Thanks for looking,
Al

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As ever, detail is in the Cerbo GX manual Section 11.4.1, extract below, same will be in the CCGX manual.

Solar is prioritised first, then the Orion XS DC-DC battery charger and then the inverter/charger.

If your generator is ac and feeds the inverter then priority depends on how they connect to the Multiplus.

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Thank you, I will go and absorb, I must have used incorrect search terms, or spelled them incorrectly, because I couldn’t find that. Honestly it didn’t occur to me to just look up the manual, I cam be a bit thick or at least blinkered sometimes!

Very much appreciated.

Given that I have both, I guess I will be reading both the Cerbo and CCGX versions, it will be interesting to see if there are any differences.

EDIT…
It appears to be the same manual and for current limiting at least, I have yet to look further the functionality looks the same too.

I am not going to describe what I have just read, it wouldn’t help and there is likely context I stull haven’t appreciated.

Save to say it ‘appears’ to be possible to limit charge from the grid without limiting solar charge, provided the mechanism/algorithm was appropriately constructed.
This seems to hold even if a BMS is in the mix, with the manual stating that, the lower of the two required limits would be applied, should the BMS be requesting a different limit than the one manually set.

Since I know the manual limit can me set from Node-Red, I am assuming, for now at least, a dynamic limit could be applied, that wouldn’t compromise the system were it to be set to high for the battery state.

Much to read, and stuff to test.
These are just my thoughts after a quick look, and could be way off.

Thanks again… and happy to be corrected if I have misunderstood anything.

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You must get fed up saying that… Sorry.

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Yes, you can set charge limit from the Multiplus via Node Red or via ac input limit.

The programming of CCGX and Cerbo are identical, the differences are all in input / output connections and hardware.

I have just reviewed the next version of the GX manual as an external pair of eyes for Victron so I know it well at the moment.

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