vennenskevin avatar image
vennenskevin asked

EV Charger Automatic charging without ESS System

Is it possible to charge in "Auto" mode when no battery system with ESS mode is present in the installation.

At the moment, there is a grid connected inverter.

We would install a Cerbo GX with energy meter for the grid, and an energy meter for the AC-Consumption.

cerbo gxEnergy Meterev charging station
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Officially, it is not possible.
Unofficially it is. :)

Please have a look at the Modbus TCP registers for EVCS, there is a parameter at address 5068. If you enable it, it will emulate a connected battery.

Download it from here -


Remember, we are not offering support for features like this.

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vennenskevin avatar image vennenskevin Lucian Popescu (Victron Energy Staff) ♦♦ commented ·


we're trying to figure it out!

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1 Answer
code-chief avatar image
code-chief answered ·

Thanks @Lucian Popescu (Victron Energy Staff) here are some example instructions as an answer:

  1. Enable MODBUS server in the EV Charger general settings, add your PC to the whitelist, save.
  2. Download a MODBUS tool like PowerHud Modbus Tester.
  3. Start Modbus Tester, enter the EV Charger IP address, select function "06-Write Single Register" with "Register Start" set to 5068.
  4. Click "Connect", you should see the register appear in the "Values" table with a value of 0 when disabled/default.
  5. Double-click the "Values" table register 5068 value 0 cell, enter the value 1 then click "Send".
  6. The battery value in the EV Charger web interface should change to 100%, if automatic charging is enabled it should start after a short countdown timer displayed under the car diagram.
  7. I had to lock then unlock my car via the key fob to get it to re-attempt charging after being stuck in the previous mode. If the car doesn't start charging automatically try physically re-connecting.



The only down-side I note is this warning in the settings page:


My use case is a pre-install of the EV Charger and GX (Raspberry PI in my case) on a building site before later delivery of the Victron inverters and batteries.

As a software developer, I guess the real bug (at least for my use case) is the Grid is not seen as available without a meter? I guess that's for safety, but it would be nice to override. It has nothing to do with a "backup battery", and shouldn't the workaround be to simulate the grid meter not the battery?

As a general idea for the Victron developers, I'd ask them to consider that it's not the concern of the Victron EV Charger what the ESS system or battery is/doing, just that it's a consumer with a preferred/optimizable usage pattern, like a heat pump. Only the GX/ESS system should concern itself with where the energy comes from. Perhaps the software, settings and limitations/workarounds would be simplified if the EV Charger firmware and settings were re-designed as ONLY a smart consumer, and the GX/ESS OS would benefit from some generic design/protocol/API for smart/dynamic loads (heat pumps, EV chargers, etc...). The new Dynamic ESS feature appears to be going down this route, perhaps update the EV Charger as a "dynamic load" as a new simplified ìntegration concept?

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Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.