question

Switching the Multiplus off releases the MPPT from the ESS control. And the MPPT starts charging as soon as enough solar power is available. The good things is that it will save another 4W of idle power.

However, that also turns off AC-Out which disables the UPS functionality.

So I'm still hoping that I can keep the MPPT alive without turning off the Multiplus.

@tom w

https://community.victronenergy.com/questions/128814/how-to-control-charge-current-of-multiplus-with-no.html

See Mr Happy's answer

@Alexandra

Thanks for the link.

Unfortunately I don't want to limit the charge current, I want to put the Multiplus into Passthrough when I don't have AC coupled PV excess available because my house consume all my AC Solar power. The Multiplus consumes an extra 20W from the grid for doing nothing but waiting for AC excess. Doesn't sound like much savings but can be almost half a kWh per day when there is a day without solar excess.

I had the same issue and found a solution on my own:

https://community.victronenergy.com/questions/108242/ess-assistant-017e-suggestionimprovement.html

P.S.: Sorry, didn't get the link to work. Please copy & paste.

@DirtyFrank

I'm unable to determine my ESS assistant version. As far as I understand VE.Config is using the assistant that belongs to the FW version of the Multiplus, in my case 481.

Are you suggesting to downgrade the FW version?

There is an official document from Victron on how to load old assistant versions. I hope that posting part of it here does not violate any forum rules:

[...]

The assistant files can normally be found in the “C:\ProgramData\VE Configure tools\Assistants” directory.

(Note that the ProgramData is a hidden directory.)

Each filename ends with _xxxx. This xxxx is a hexadecimal unique number. It can be regarded as the assistant version number.

[...]

Now if you want to configure a system with for instance the ESS_0164 you should do the following:

1. Close VEConfig
2. Change the extension of all ESS assistant files with a higher hexadecimal number to for instance “vapx” [...].
   (You can also choose to move these files to a temporary directory.)
3. Restart VEConfig

[...]

P.S. (by DirtyFrank):

On my system the directory is C:\Users\Public\VE Configure tools\Assistants.

P.P.S.:

Please be aware that you might probably get an error in VE Configure complaining about a non compatible assistant for the latest MP firmware versions. In that case you have to downgrade firmware temporarily, load the old assistant and configure it. Now you can upgrade the firmware again. You should then backup the old assistant (saving includes both assistant version and configuration) for easier future import (to avoid repeated downgrading). You can then still use the outdated assistant but no longer configure it (unless you downgrade the firmware again).