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semlohnhoj avatar image
semlohnhoj asked

Multi RS Solar - Ability to set ESS mode and Minimum discharge SOC via NodeRed/Modbus/dBus.

Please could a firmware update be issues to allow setting of the following on the Multi RS Solar:

1) ESS Mode ("Keep batteries charged", Optimized with/without battery life")
2) Minimum discharge SOC

Ideally, these should be setable via NodeRed, Modbus and Dbus.

If this feature is in a beta build then I'm happy to test it for you :)

I charge my batteries overnight using cheap rate electricity but this requires all sorts of fiddling using the PC verision of VictronConnect and a Macro recording piece of software as there is no way to do this automatically in the settings or via an API. I also keep the AC input disconnected during the day unless the AC output load is too high because the newer firmware draws more idle power from the grid for some reason. The new firmware v1.11 feature to allow AC input control is half way there but lacks a timed function and any charge level control.

If the two items above were available for writing then I could achieve everything I need to do via NodeRed.

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wkirby avatar image
wkirby answered ·

It is possible to do this in Node-RED. Set MultiRS Aux input to "AC-in connect" then use Cerbo relay to signal this input. It will open the backfeed relays to disconnect the AC input when you don't want it.

Use Node-RED to read the battery % and then take the action that you want. This can be used to set a lower limit and also an upper limit to stop night time charging if the next day will bring more solar power. Even better is to make the upper limit adjustable from the dashboard.
Night time charging times can be set in Node-RED to start and stop the charging to suit your cheap rate.

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semlohnhoj avatar image semlohnhoj commented ·
I've implemented pretty much that following advice from some of your previous posts.


The issue is I have the GX relay set to trigger the RS to turn on the AC Input overnight which works fine and only for the % I want but also to come on during the day if the AC load is high so the RS can do some PowerAssist. The problem is that if it does this during the day then it starts charging as well. Having the ability to either change the minimum SOC or the ESS mode would solve this.


I thought I had the answer by setting the RS to 'Inverter Only' during the day so it didn't charge when the input relay was closed and setting it to 'On' at night so it will charge. Annoyingly though, what i didn't realise is that the 'Inverter Only' setting doesn't allow PowerAssist. It seems to scupper me at every turn.

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