Anyone else using a Victron Cerbo GX with a non-Victron inverter — how are you handling the monitoring gap?

I've got a Cerbo GX at the heart of my system and it's brilliant for keeping tabs on my MPPT, BMV-712, and the Multiplus — everything talks together nicely over VE.Can and VE.Direct. The problem is I've recently added a second inverter (a Growatt SPF 3000TL LVM) for some heavier loads, and the Cerbo has absolutely no idea it exists. So my consumption figures on VRM are completely wrong, sometimes showing the system as producing energy when it's clearly pulling from the batteries.

I've been looking at a few workarounds. One option is adding a Victron AC current sensor on the Growatt's output and feeding that back to the Cerbo, but I'm not 100% sure that gives me proper bidirectional readings or integrates cleanly into the energy dashboard. The other idea is a Shelly EM clamp on the output circuit, pulling data into Home Assistant and then patching it into VRM via the MQTT route — but that feels like a lot of duct tape for what should be a fairly standard setup.

Has anyone actually solved this properly? Ideally I want accurate kWh figures in VRM rather than just a live watt reading, and I'd rather not rip out the Growatt if I can avoid it. System is a 24V setup, 400Ah of lithium, about 1.2kW of panels if that's relevant. Any pointers appreciated.

Hey @NickEvans — yeah, I've been down this road! I've got a Growatt inverter alongside my Cerbo and the monitoring gap is real. What I've done is run the Growatt's RS485 output into a cheap Modbus-to-USB adapter, then use a Raspberry Pi running Node-RED to pull the data and push it into the Cerbo via MQTT. It's not plug-and-play by any means but once it's set up it's solid enough.

The key thing is getting the right Modbus register map for your specific inverter — manufacturers aren't always great at publishing these, so worth checking the relevant forums or GitHub repos.

You can then get everything displaying together on VRM which is the goal really. Happy to share my Node-RED flow if it'd help — saves a fair bit of head-scratching!

Good shout on this topic. Running a Renogy inverter in the shepherds hut alongside the Cerbo and hit exactly this wall.

What worked for me — grabbed a Victron Energy Meter (the ET340) on the AC output side. Cerbo picks it up over USB-MK3 and at least you get real power draw visible in VRM. Not perfect native integration but fills most of the gap for practical monitoring.

The other route worth looking at is a Shelly EM clipped onto the output — pulls into VRM via the Modbus TCP workaround some folk have documented on the Victron community forums. Bit fiddly to set up mind.

Neither gives you full bidirectional comms with the inverter itself, but for knowing what's actually being consumed it does the job. What's the Growatt model @Chris1977 — some of them have their own Modbus registers you can tap.

Great thread! I'm running a Victron setup alongside a Solis inverter and solved a chunk of the monitoring gap using a Raspberry Pi with Node-RED pulling data via Modbus, then pushing it into the Cerbo's MQTT broker. Gives you a consolidated view on VRM which is handy.

Worth noting that the Cerbo does have a "third-party inverter" device option under its device list — it won't give you deep telemetry but at least acknowledges the device exists in your system overview.

@NickEvans and @ST_Builds — another option worth exploring is a Victron Energy Meter on the AC input/output of your non-Victron inverter. Doesn't give you inverter-specific data but you'll at least see the power flows properly on the dashboard. Not perfect but better than a blind spot in your monitoring!

Had this exact headache when I bolted a cheap Giandel inverter onto my Victron setup before I could afford a Multiplus.

What worked for me was wiring a Victron ET112 energy meter on the inverter's AC output — feeds real power data straight into the Cerbo via USB. Not perfect but you get actual wattage showing up on VRM at least.

Other option worth considering: if your inverter has any kind of RS485 comms port, there are community-built Node-RED flows that can bridge the data across. Bit of faffing to set up but @RustyCaptain probably knows more about that side of things than me.

Long term honestly just save up for a Multiplus and be done with it — the integration is night and day compared to bodging third-party kit together.

Really useful thread this. One thing I'd add that hasn't been mentioned yet — if your non-Victron inverter has any kind of Modbus or RS485 interface, it's worth looking at whether Node-RED on the Cerbo can bridge the gap. You can pull data from the inverter, massage it, and push synthetic values into the Cerbo's DBUS, which then shows up in VRM almost as if it were a native device. It's a bit fiddly to set up but once it's running it's solid.

@RustyCaptain curious what approach you landed on with the Solis — those do have a Modbus interface IIRC so potentially good candidate for exactly this.

Not a perfect solution for everyone but if you're comfortable tinkering it's far cheaper than replacing a perfectly functional inverter just to get native monitoring.

Good timing on this thread — I'm running a Victron Cerbo with a Studer inverter-charger on my narrowboat and faced exactly this.

What worked well for me was using a CT clamp on the AC output wired into a Carlo Gavazzi EM24 energy meter. The Cerbo picks it up over RS485 and actually displays it properly in the VRM portal as "AC loads" — it's not perfect integration but it's surprisingly clean. You get real-time wattage, daily kWh, the works.

@VanBarry is right that any native comms your inverter has is worth exploring first, but for those where that's not an option the EM24 route is genuinely solid and not massively expensive. Carlo Gavazzi units are around £80-100 if you shop around.

Main limitation is you're reading AC output only — you won't get fault codes or inverter temperature feeding through to Cerbo. That side remains a manual check unfortunately.

Good shout from @SomersetBoater on the Studer — those have Xcom-CAN which can be coaxed into talking to the Cerbo via a custom driver, though it's fiddly.

What I've found works reliably for truly dumb inverters is a clamp meter energy monitor (I use a Eastron SDM120 on the AC output) feeding into a Node-RED flow on a Raspberry Pi alongside the Cerbo. You can push synthetic data into VRM via MQTT using Victron's dbus-mqtt — the inverter then appears as a "generic load" tile.

Not elegant, but VRM graphs stay coherent and you get AC output wattage logged properly. Took an afternoon to configure but hasn't missed a beat since.

Ran into this exact issue setting up my shepherd's hut. Ended up fitting a Shelly EM on the inverter's AC output — gives me real-time wattage fed into Node-RED, which then pushes values to the Cerbo via MQTT. Not perfect native integration but it works reliably and the Shelly was about £25.

Worth noting that if your inverter has a RS-485 port, there's a decent chance someone's already written a driver for it on the Victron community forums. Searched for mine and found a half-finished Python script that needed minor tweaking but saved hours.

Really useful thread this. To add another angle — if your non-Victron inverter has any kind of RS485 or Modbus interface, it's worth checking whether there's a community-built driver for VenusOS. I've seen people get surprisingly good integration that way, pulling actual inverter data rather than just inferring it from clamp meters. The Victron Community forum has a dedicated section for Venus OS large/modifications where devs share these drivers. Obviously it's a bit more technical than a plug-and-play solution, but if you're comfortable with SSH it opens up a lot. Which inverter are you running @NickEvans?