Grid ussage predictions are Off

Q&A and troubleshooting DESS
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Hi Everyone,

Since 4 weeks i am owner of a Victron based home battery system.
At the moment my whole house, including the 1 phase 32A EV wall charger is behind the multi’s output. These are 2 48V 3Kva Multi’s.

I noticed Dess makes strange calls and prediction, i think becouse of the EV charger that is currently on the AC out.

I want to solve this by adding an extra grid meter( VM-3P75CT) (metering is now done inside the multi’s).

However, Peak load shaving is important for me since my grid connection is also 32A. If i move the EV charger to the AC in side would perhaps be a problem becouse of this.

Only loads directly supplied from my main connection would then be the multis (internal metering) and the AC EV charger ( VM-3P75CT meter). Does peak load shaving than still work?

How to exlude this charger from my ussage to prevent mixing up all energy predicitons?

Thanks in advance for tips and tricks.

1 Like
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Hi Lars, I have a similar configuration: charger on AC input and the rest on AC output. If the car is charging and overload is imminent, the MultiPlus (if sufficient battery capacity is available) will prevent this by applying peak shifting (if properly set). If you’re also using DESS and overload is threatened because the battery is being charged, the power towards the battery will be reduced.
Hopefully, this is the answer you were looking for.

Kind regards, Maykel

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Hi Micheal,

Thanks for your advice!
I have now added an extra VM-3P75CT in the system.
I connected the charger to AC in side of the inverter. First i hooked it up as a AC load. Then peak load shaving is not working properly and you can not set where the load is (AC in or out). Then i changed the grid metering from the multi to the VM-3P75CT. This makes VRM show critical loads and loads seperatly. Now the load is the EV charger, and the critical loads is all the rest. When i started testing Peak load shaving was not working. Peak load shaving only seems to work for critical loads. At the moment this did not solve the problem. Anyone has another suggestion?