DESS on a MultiRS system with both AC and DC based solar

Q&A and troubleshooting DESS
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Hi,

I run a 3-phase MultiRS based system with a number of solar panels connected to a 3phase AC SolarEdge inverter connected to AC-Out as well as a number of panels connected directly to the MultiRS MPPTs.

To the DESS system (as far as I know) all this solar energy is treated the same, and there is only a single efficiency figure deciding whether it is wiser to store energy in my battery, or return it to the grid rightaway.
Technically I would assume that the Victron MPPT sourced solar energy (being DC already) would require only 1 DC/AC conversion (solar->battery->grid) whereas the SolarEdge energy would need to be converted AC->DC->AC if being stored at first and need no DC/AC conversion if being returned to the grid directly.

In NodeRed I am able to disable DESS temporarily and control the MultiRS to charge the battery with only the MultiRS MPPT energy and forward the SolarEdge energy directly to AC-in.
Obviously turning off DESS temporarily gives me some issues when I turn on DESS again with a higher SOC, since DESS tries to go towards the (previous) target SOC first before a recalculation considers the new SOC and makes an improved SOC plan/forecast.

I have noticed temporarily setting my system to PassThru gives me more or less the same effect regarding solar energy flow without having to turn off DESS and actively control the grid setpoint from NodeRed.
Are there negative consequences to setting my MultiRS to Passthru for a few hours every day when I prefer to store the Victron MPPT energy and return the SolarEdge energy directly to the grid?

DESS is generally working quite well for me, but sometimes I want to override the DESS choices manually.
Manually altering the target SOC schedule works to some extent, but is not my preferred option.
Setting DVCC Charge current limit allows me to prevent battery charging.
Setting ESS Mode to ‘keep battery charged’ allows me to force battery charging.

any feedback on other approaches to slightly nudge DESS a bit without replacing it fully are appreciated.

kind regards,

Guy

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I have Multiplus 5000 instead of a MultRS, but I guess the DESS stuff works the same.

As I was not so happy with the DESS behaviour I did something similar. I have DESS running, but the Multiplus set in mode 3 (external control, I think thats what you call passthrough).

This does not seem to give any issues. DESS still makes the planning for me, but I do the charging and discharging myself using Node-Red.

Whenever the SOC deviates from the planned SOC, VRM will eventually update (usually within an hour). So I think flipping between external control and optimized should not give you much problems, except as you mentioned, if the soc schedule is not updated quick enough it might start dumping energy back to reach the SOC (as I don’t switch out of external control, i don’t have that issue).