Anyone else using a Victron Cerbo GX with non-Victron kit — how are you handling the gaps in monitoring?

Just finished wiring up my van build and I've got a Cerbo GX as the brains of the operation. I'm running a Victron Multiplus-II 12/3000, a SmartSolar 100/30, and a 200Ah lithium from a smaller Chinese brand (CATL cells, decent BMS but no Victron integration). The Cerbo picks up the inverter and MPPT no problem over VE.Can and VE.Direct, dead easy. But obviously it knows nothing about what's actually happening inside the battery — no SOC from the BMS, no cell-level data, nothing.

I've bodged it for now by adding a Victron SmartShunt on the negative bus, which at least gives me a coulomb-counted SOC and the Cerbo can display it. But I've had to manually dial in the battery capacity, charge efficiency, and Peukert exponent, and I'm not fully confident my numbers are right. After a few days of use the SOC seems to drift a bit — reads about 8% higher than I'd expect when I check voltage against a rough state-of-charge table for LiFePO4.

Has anyone cracked a better solution for third-party lithium monitoring on the Cerbo? I've seen people mention the VenusOS large image with Node-RED for pulling in BMS data over Bluetooth or RS485, but I've never touched Node-RED in my life. Is it actually manageable for someone who's comfortable with basic config but not proper coding? Or is there a simpler bit of kit I'm missing?

@Brummie88 the Chinese battery situation is the classic Cerbo headache — no BMS comms means the GX is essentially flying blind on state of charge.

What sorted it for me on my motorhome build was running a Victron SmartShunt inline. It feeds proper coulomb-counted SOC data back to the Cerbo over VE.Direct, so suddenly everything talks sensibly regardless of what the battery thinks it's doing.

The other gap I hit was temperature — my Fogstar cells weren't reporting anything. Cheap Dallas DS18B20 sensor wired into a Raspberry Pi running Node-RED alongside the Cerbo filled that hole nicely, pushing data into VRM via MQTT.

It's a bit of a patchwork, admittedly — but once it's running, the VRM dashboard actually becomes genuinely useful rather than half-guessing.

What BMS does your Chinese pack use? Some have a UART port that's worth exploring.

@Brummie88 been down exactly this road on my narrowboat. What saved my sanity was wiring a Victron Smart Shunt between the battery and the rest of the system — it's not the same as proper BMS comms, but the Cerbo picks it up natively over VE.Direct and suddenly you've got SOC, current flow, voltage history, all sitting nicely on the dashboard.

The gaps I couldn't fill through the Cerbo I ended up patching with a separate Bluetooth BMS app running on an old phone mounted near the helm. Inelegant but it works.

One thing worth checking — some of the Fogstar and similar cells ship with a JK BMS that has a RS485 port. With the right cable and a bit of fiddling you can get that talking to the Cerbo via Venus OS. Proper integration rather than guesswork.

Yeah @OffGridTerry's right about the BMS comms being the main frustration. @Brummie88 one thing worth trying if your battery has a JBD or JK BMS — there are community-built integrations that can pull data over Bluetooth or RS485 into Node-RED, then push it to the Cerbo via MQTT. It's a bit of a faff to set up initially but once it's running you get SOC, cell voltages, temperatures, the lot appearing in VRM alongside your Victron kit.

Alternatively, a Victron BMV-712 sitting between the battery and load bus gives the Cerbo something solid to work with even without direct BMS comms. Not perfect but it's reliable and dead easy to configure. Many of us running mixed systems have gone that route as a pragmatic middle ground.

What BMS does your battery actually have? Might narrow down which approach is worth pursuing.

@Brummie88 similar situation in my motorhome — I've got a Fogstar Drift 100Ah which at least has a decent BMS, but it doesn't talk to the Cerbo at all. What I ended up doing was adding a Victron SmartShunt between the battery and the rest of the system. It's not perfect but the Cerbo picks it up via VE.Direct and you get proper SOC, current draw, and voltage on the dashboard. Way better than relying on the MPPT's estimates alone.

Worth asking — what are you actually missing most? Is it SOC accuracy, temperature monitoring, or the BMS protection data? Because there are different workarounds depending on what matters to you. The SmartShunt sorted about 80% of my frustrations but temperature still shows as unknown which bugs me slightly.

Good thread this. @Brummie88 one thing nobody's mentioned yet — have a look at the Node-RED integration if you're comfortable with a bit of tinkering. The Cerbo runs Venus OS and you can unlock some surprisingly useful custom dashboards and alerts that way. Helped me fill a few monitoring gaps with my own mixed setup. Also worth checking whether your BMS has a UART or RS485 output — there are community-built drivers that can sometimes pull state-of-charge data straight into Venus OS even from cheaper Chinese batteries. No guarantees obviously, but it's worked brilliantly for a few lads on here. Main thing I'd say is don't stress too much about perfect monitoring from day one — get it running, live with it a few weeks, and you'll soon work out exactly what data actually matters to you.