VRM Dashboard reporting show phantom grid export on 3-phase MultiPlus-II with Enphase PV

Bit of an odd one cropping up on my barge setup that I reckon some of you 3-phase folks might recognise.

Running a pair of Victron MultiPlus-II 48/3000 units (not quite full 3-phase, more a split arrangement) with Enphase IQ8 microinverters on the cabin roof, and the VRM dashboard has started showing grid export figures that simply cannot be real — we're nowhere near the grid, full stop. Completely off-grid. So where's VRM conjuring these numbers from?

My suspicion is the CT clamp positioning combined with how VRM interprets the Enphase Envoy data. When the micros are pushing hard on a sunny afternoon and the MultiPlus units are simultaneously charging the Fogstar Drift lithium bank, the monitoring seems to get confused about energy direction and just... invents an export figure.

Has anyone else seen this on a proper 3-phase MultiPlus-II configuration? I'd imagine it's potentially worse there because you've got three legs to misread rather than two.

Things I've already tried:

• Recalibrating the ET340 meter
• Checking Enphase Envoy CT orientation
• Toggling the "has DC system" flag in VRM settings

None of it's shifted the phantom figures meaningfully.

Would love to know if this is a firmware quirk, a known VRM reporting bug, or something fundamentally wrong with how Enphase and Victron communicate energy flow data to each other. The Victron community forum has a few vague threads but nothing definitive.

Anyone cracked this?

@FormerMariner36 seen something similar on my boat setup, though I'm only single phase. Worth checking whether your Enphase IQ gateway is reporting production data to VRM via the Envoy integration — there's a known quirk where the CT clamp orientation on the Enphase side can cause the Victron CCGX to misinterpret net metering figures as active export.

Also, are you using an ET340 or EM24 grid meter? On split-phase/quasi-3-phase arrangements the phase assignment in VEConfigure matters enormously. I've seen VRM happily phantom-reporting 400W "export" on L3 when that leg wasn't even properly configured.

Check your ESS assistant settings too — specifically the "feed-in excess solar" checkbox. If that's enabled but your DNO agreement doesn't permit export, you can get ghost figures appearing.

What firmware are you running on the GX device?

@FormerMariner36 classic VRM phantom export issue. The Enphase microinverters report production slightly ahead of what the MultiPlus sees via the AC coupling feedback loop, so the MPII momentarily "sees" more AC power than the loads can absorb — VRM logs that delta as grid export even on an islanded system.

Few things to check:

• Grid setpoint in ESS — if it's set to 0W you'll get this artefact; nudge it to +50W
• Make sure your Envoy is on the same VRM network and you've got the Enphase PV integration running through Venus OS rather than relying purely on AC clamp readings
• Check your frequency shift settings — if curtailment isn't kicking in fast enough the MPII logging gets confused

Had something comparable on my shepherd's hut AC-coupled setup. Sorting the ESS grid setpoint fixed 90% of the phantom readings immediately.

Hey @FormerMariner36, interesting one this! On barge setups I've seen the CT clamp positioning cause mischief with readings like this — particularly if yours are clamped anywhere near the engine room wiring where you might be getting inductive interference from the alternator or bilge pump circuits.

Worth double-checking your VRM settings under Advanced > Energy Meters and confirming the role assigned to each meter is correct for your split-phase arrangement. Victron's documentation for non-standard 3-phase configs can be a bit woolly, and an incorrect role assignment can absolutely produce phantom export figures even when you're nowhere near the grid.

Also, what firmware are you running on the CCGX or Cerbo? There were some reporting quirks in earlier versions that played havoc with microinverter setups specifically. Might be worth checking the changelog on the Victron community site.

Wondering if the CCGX or Cerbo GX firmware version plays into this at all? Had something vaguely similar crop up on my shepherd's hut build where the VRM portal was showing readings that didn't match what was physically happening — turned out to be a polling interval mismatch between the Cerbo and the inverter.

With Enphase specifically, their Envoy gateway has its own reporting cadence that doesn't always sync cleanly with Victron's data logging intervals. Could that be creating the phantom figures rather than it being a genuine measurement error?

What firmware are you running on the MultiPlus-II units? Also, are you monitoring via a GX device or direct to VRM? Might help narrow down whether it's a display/reporting artefact or something the ESS assistant is actually acting on.

@FormerMariner36 curious whether you've checked the AC coupling settings in VEConfig? Had something similar with my Fogstar batteries and a single-phase setup — the system was briefly seeing battery discharge as grid export during the handoff between PV sources. Might be worth looking at the feed-in sustain voltage threshold too, since if that's set too low the MultiPlus could be flickering in and out of feed-in mode, which VRM then logs as export events. What firmware are you on for the MultiPlus-II itself? Sometimes the VRM reporting and the unit firmware get out of sync on how they classify AC current direction.