Dynamicly change grid setpoint due AC out2 shortcomings

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Hi all,

I have setup a 3 phase Multiplus 5000 system with 50kW of battery storage. I wired the EV charger on the AC out2.
During the design phase I was under the assumption that AC out2 loads would never come from the battery bank. As I now figured out the hard way, this is not the case. When I start charging my EV the energy comes unfortunately from the battery.

Since my system is grid tied, I only want to use Grid energy to charge my EV´s. And I preferably do not want to change the Tesla wall connector to the AC IN side.

My proposed starting solution would be this to dynamicly set the ESS grid setpoint to 11000 when charging my car. Then the required power will be fed in from the grid, additional house consumption would come from the battery. In a later stage I can dynamicly get the charging voltage via a S0 meter or via the Home Assistant tesla instance / or mqqt.

Does this seem like a feasible / workable solution? In my mind it would make the AC out2 port a little smarter via software?

Kind regards,

Frank

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Best way is to set the system to keep batteries charged or min soc to 100% during EV charge times ( in ESS.)

The other way is to move the EV load to before the inverter and have a grid meter and then set discharge battery to critical loads only.

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Both options require software solution.

If I set min SOC to 100% or keep batteries charged the charger would kick in for the home battery too.

Also, if i move the load to the inverter side i need to dynamicly change the max inverter AC in value. I have it now at 25 amps. But if EV inverter is there too it might go over 25A when the system decides to start filling the home battery.

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Yes. Software control.
If you don’t want to keep batteries charged then you just stop discharge by freezing the soc where it is. And peak shaving can be still allowed at min soc.