EG4 12000XP Off-Grid Inverter V2 with no backfeed to the grid if I hook up L1 and L2 grid tie?

Interesting one this — I've been watching the EG4 kit with curiosity for a while but it's not exactly common over here in the UK.

My understanding is that most hybrid inverters can be configured to prevent backfeed through a combination of software settings and CT clamp monitoring, but whether the 12000XP specifically handles this reliably with both L1 and L2 connected is another question. The anti-islanding and export limitation features vary quite a bit between firmware versions.

A few things I'd want to know in your situation:

• Are you on a G98 or G99 application with your DNO? Because if you're export-limiting to zero, that needs to be demonstrably reliable, not just "probably fine"
• Is the CT placement correct for both legs? Poor CT positioning is often where these setups fall apart
• What firmware version are you running?

On my narrowboat setup I use a Victron Multiplus-II with a Carlo Gavazzi meter for proper grid monitoring, and even with that well-documented combination it took some careful ESS configuration to get genuine zero-export working consistently.

The EG4 gear seems popular Stateside but I haven't seen many UK installs with DNO sign-off using it. Has anyone here actually got one approved and running with confirmed zero-export logging?

Would be genuinely useful to hear from someone who's done the paperwork side of this properly rather than just assumed it's working.

@GeoffHenderson80 really interesting question — I've been down a similar rabbit hole with my motorhome backup setup!

From what I understand, the EG4 12000XP does have a zero export / anti-backfeed mode you can enable in the settings, which essentially monitors grid draw and throttles inverter output accordingly. Some folks achieve this using an external CT clamp setup feeding back to the inverter.

Worth noting though — for UK grid-tied installs you're really in G98/G99 notification territory, and most DNOs get twitchy if the anti-backfeed isn't certified to their standards. Even with software limits, they may not accept it without proper documentation.

Has anyone on here actually got EG4 kit past a UK DNO? That's the bit I'd be genuinely curious about — seems like Victron's ESS with zero feed-in is the more well-trodden path domestically for this exact reason.

Worth noting that the EG4 range is very much designed around the North American split-phase 120/240V setup — L1 and L2 there aren't the same animal as our single-phase 230V system here.

I spent a fair bit of time researching alternatives before settling on a Victron Multiplus-II for my static caravan setup, partly because the documentation around grid compliance (G98/G99 in our case) is actually coherent and the UK installer community knows it inside out.

If you're determined to run an EG4, the "no backfeed" question becomes almost secondary to whether it'll even play nicely with DNO requirements here. The anti-islanding protection configuration is where I'd be digging first.

@ExTrucker73 — the motorhome world has slightly more flexibility given it's typically off-grid by nature, but a grid-tied residential install is a different compliance conversation entirely.

@EcoFlow_Master is absolutely right and that's the crux of the issue — the EG4 12000XP is built around 120/240V split-phase which simply doesn't translate to UK 230V single-phase without significant workarounds.

On my narrowboat I run a Victron Multiplus-II 48/5000 which handles zero-export via the Victron ESS assistant properly on our 230V system. That's the architecture you actually want if you're worried about backfeed — the ESS current sensing is solid and DNSP-compliant.

For UK off-grid use the EG4 is essentially a square peg in a round hole. You'd be fighting the firmware constantly and there's no MCS or G98/G99 compliance pathway that I'm aware of, which matters if you're grid-tied at all. Stick with Victron, SolarEdge, or Solis — all have proper UK zero-export configuration and decent UK distributor support through the likes of Bimble or Solar Voltaik.

@ExSquaddie49 makes the key point well. From a purely practical standpoint for UK use, you'd be fighting the hardware at every turn — 230V single-phase is just fundamentally different architecture to what the EG4 is designed around.

I've run a Victron Multiplus-II in my motorhome setup with zero-export configured via the grid meter, and honestly for anyone wanting proper UK grid compliance that's the sensible route. The G98/G99 requirements here mean your DNO needs to approve any grid-tied setup anyway, and submitting paperwork for a unit that wasn't designed for our grid seems like unnecessary pain.

If budget is a concern, there are some decent Deye and Solis hybrids now available through UK distributors that come pre-configured for 230V and have MCS/G98 compliance sorted — far less faff overall.