Multiplus2-gx + solaredge + lg-chem

Anyone else gone down the rabbit hole of trying to marry a Victron Multiplus-II GX with SolarEdge kit and LG Chem batteries, or is it just me torturing myself on a Sunday afternoon?

Running a similar hybrid mess on my motorhome setup (scaled down, obviously) and the comms protocol headaches between different manufacturers are real — CAN bus arguments that'd make your head spin.

The bit I'm genuinely curious about is how you'd handle the import/export metering when SolarEdge's StoreEdge is already wanting to be the boss of the LG Chem, while Victron's GX is sat there also fancying itself as the system manager. Two prima donnas, one stage.

A few things worth thrashing out:

• DVCC settings on the GX — anyone actually got this playing nicely with non-Pylontech batteries in a mixed setup?
• Does SolarEdge's modbus talk to the GX cleanly, or are you bodging it with a third-party integration?
• G98/G99 compliance — because whatever you build, the DNO will want paperwork before you export a single watt in the UK

Pylontech is basically the Victron ecosystem's favourite child, so swapping that dynamic for LG Chem feels like telling your dog it's getting a new owner — possible, but expect sulking.

Genuinely interested if anyone's got a working three-phase config here in the UK — drop your wiring diagrams, sob stories, whatever you've got.

Hey @BenJackson, you're definitely not alone in that particular circle of hell! 😄

The tricky bit with this combo is that SolarEdge and Victron don't play nicely natively - SolarEdge speaks its own language and the Multiplus-II GX wants to be the boss of everything. What inverter model are you running on the SolarEdge side?

The LG Chem RESU should actually be the least of your worries here - Victron's DVCC handles that reasonably well once you've got the CAN bus sorted properly.

Main thing I'd flag is you'll likely need the SolarEdge Modbus TCP integration and possibly a bit of Node-RED wizardry to get proper communication flowing. What firmware version are you on for the GX? Some earlier versions had real headaches with third-party inverter comms.

Tell us more about your full setup and we can dig into it properly.

Been down this exact rabbit hole about 18 months ago @BenJackson - what a fun weekend that was 😅

One thing neither of you have mentioned yet - make sure your SolarEdge inverter has the SetApp enabled and you're running firmware that supports the Victron integration properly. The LG Chem RESU talking to the Multiplus-II GX via CAN bus is generally solid once it's configured, but the SolarEdge side can be a right pain if the export limiting isn't set up correctly alongside it.

What's your grid connection situation - single phase or three phase? That changes things quite a bit with this particular combo. Also worth checking which generation RESU you've got as the older units have slightly different CAN bus behaviour.

Happy to share my config notes if it helps, saved me a fair few hours of head-scratching!

Oh this thread has pulled me in because I went through exactly this saga last summer with my static caravan setup! 🙈

The bit that nearly broke me was the AC coupling configuration — SolarEdge doesn't always play nicely out of the box with the Multiplus-II GX's frequency shifting mechanism for export limiting. Victron's own documentation is a bit vague on the SolarEdge side specifically.

What actually saved me was digging into the Victron Community forum (not just here!) and finding that you sometimes need to fiddle with the SolarEdge inverter's grid protection settings manually to match what the Multiplus expects.

@BenJackson what firmware versions are you running on both units? That genuinely matters more than people realise with this particular combo — I'd been running outdated SolarEdge firmware and it was causing phantom disconnects that drove me absolutely mad.

Worth flagging something nobody's mentioned yet — the LG Chem RESU has its own BMS that communicates via CAN bus, and getting that talking nicely to the Multiplus-II GX can be a bit hit-and-miss depending on firmware versions on both ends.

Few things I'd check:

• VEConfigure — make sure your battery type is set correctly, not just "lithium" generically
• SolarEdge's export limiting can sometimes confuse the Victron's frequency shifting — worth disabling SetApp export control temporarily just to isolate issues
• Check your VRM portal logs for any BMS disconnect events, easy to miss

Had similar headaches with my garden office setup before I switched to Fogstar cells. The LG Chem units are solid but they're fussy about comms dropouts causing unnecessary shutdowns.

What firmware is your GX running @BenJackson? That's usually where I'd start.