Solaredge Power Control via Cerbo

Node-RED
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Hi all,

I have a 3x Multi RS set-up with a Cerbo GX.
On the AC_out, I have a SolarEdge SE8k (8 kwp) which I currently control via my regular home automation system, through Modbus.

The automation doesn’t do much exciting stuff. Mainly it controls the Power Limit (%) in case of:

  • Negative electricity tariff (set to 0)
  • Tune power factor to have net 0 on the meter in case the export price is negative, but import price still positive (e.g. Pf = house consumption / 8000)

Now, I would like to shift this stuff to Victron (prefer to avoid multiple devices controlling the SE). I’m convinced it can do it, because all the options seem available in Node-RED and the SolarEdge menu on the Cerbo shows that it supports the active power limiting.
But it’s not clear to me what the right way is to implement this.

Questions I still have:

  1. Is there a way - outside Node-RED - to have the Cerbo or Multi’s control the SolarEdge Power Limit? E.g. via the ESS? So far, I have not found an option that triggers the system to limit solaredge production.
  2. I’m familiar with Node-RED and noticed that there’s a function to set the production limit via the Custom Control Node - - /Ac/PowerLimit. This is a value in watts and represents the total 3phase production limit. e.g. 400 watts. Victron sees this value correctly in the device window when I set it.
    However, it returns to the original full capacity (in my case 8400 W) after 20 seconds or so. Is that expected behavior, e.g. does the ESS also try to control this value in parallel? Or I’m just supposed to inject the power limit value every few seconds to keep it active?

Thanks in advance!

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Correct. You have to keep injecting the value.
Other than frequency shifting this is the only way to control it.

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Thanks!

And this won’t conflict with other functions in the ESS? It’s unclear to me from the manual if the Cerbo will try to control the same parameter as well, e.g. based on the grid setpoint. (I can also move this question to the non-nodered topic)

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I haven’t had an issue with the fronius i was power limiting based on a different need, i just also noted that i had to send the limit repeatedly as you did.
ESS does move the grid set point but as we also have dc mppts it was filling in other gaps.
The inject i am doing is based on percentage of load as the limit. So its a combination of a function and maths with the inject.

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I am interesting in the power control. What is the code implementation for Cerbo Gx because the info above is not clear.

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As specified in my original post:

I don’t know how to make it more clear than that, it’s very straight forward to set the limit in terms of total power (in watts) via the custom control node. Where do you get stuck?

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I still not understand.

Is Custom Control node a flow inside the NodeRed applicaton within CerboGx? If so, give me a screenshot within the NodeRed editor.

Is this node not needed anymore because Cerbo has the control to SolarEdge via ESS?

Another question:

There is a wire connection between Victrons AUX Relais (NO + COM) to interconnect to Solaredge Communication Board (L1+V). See details: Overvoltage, Cerbo GX controlling SolarEdgePV, Sunspec: ‘Dynamic power limiting’ option not working - Q&A and troubleshooting - Victron Community

Is it only relevant for frequency shifting?

Should we replace a communication board within SolarEdge SE10K from year 2020?

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Please read the basics of Victron’s NodeRed implementation here. Venus OS Large image: Signal K and Node-RED [Victron Energy]

Custom Control is a node, not a flow. it’s shown on the page and also in the documentation.

I’m only using it to overrule the solaredge power limiting when I am not in an off-grid mode. If you are off-grid mode, frequency limiting does the work.