Hi all, The Venus OS supports the integration of PV inverters via TCP Modbus if the PV inverters support Sunspec. I have two suggestions for this that offer additional benefits and, according to my research, shouldn’t require too much development effort. Feature Request 1 Support for Sunspec PV …

I had an (experimental) setup with a Sunspec-compliant inverter on AC-out. It was correctly discovered by GX. PV management and communication was verified by me by using Node-Red (PV inverter / Power Limit) as well as playing around with the Grid setpoint. But I noticed that the PV is not adjusted…

@mpvader Basically I do agree. On the other hand, most TCP Modbus sticks, or even those via LAN, do nothing more than convert RTU to TCP Modbus. I’ve seen some implementations where the STCP Modbus interfaces represented a bottleneck. It’s certainly not Victron’s job to solve the manufacturers’ …

Has anyone experience with connecting a Sungrow Inverter? It’s a SG10RT with WiNet-S LAN Dongle.

Where, in Node Red, did you find the “limit calculated by venus OS”? I couldn’t find it myself.

Hi, it is part of the Victron PV Inverter Node. [image] [image]

Hmm, not here: [afbeelding] Nevermind, don’t want to hijack your topic

mhhh MQTT does not sound like sunspec modbus tcp connected inverter. Anyhow…if limiting is supported it needs to be enabled for the inverter in question. And also a Limit needs to be configured in ESS to make the limit calculation work. [image] [image]

Ah, it must be modbus connected. But then VenusOS already manages the power limit, doesn’t it? Why setting the limit youself, too?

Support of Sunspec Inverters via Modbus RTU and extended Sunspec Support

Beta testing Venus OS beta testing

Desperado September 14, 2025, 7:25pm 6

Kan het zijn dat de Sunspec regeling geen rekening houdt met max grid-feedin?

Edit: Sorry for the Dutch, I added English below:

Can it be that the Sunspec management ignores max grid feedin?

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Support of Sunspec Inverters via Modbus RTU and extended Sunspec Support

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