Grid meter, AC loads before and after Multiplus, shore current limit issue

Been scratching my head over something similar with my shepherd's hut setup and wondered if anyone else has run into this.

I've got a Multiplus-II 24/3000 with a Cerbo GX and recently added a Carlo Gavazzi EM24 as a grid meter (using shore power from the farmyard hook-up when solar can't keep up over winter). Everything looks right in VRM — single phase, readings seem sensible — but I'm getting weird behaviour around the shore current limit.

Specifically, when I have AC loads both before and after the Multiplus (some fixed sockets are wired directly to the incoming supply, pre-inverter), the system seems to get confused about how much current it's actually drawing from shore. It keeps throttling the charge current down unnecessarily, like it's double-counting something, or it's not properly netting off what's downstream of the Multiplus versus what's upstream.

Few questions for the collective brain here:

• Does the position of your grid meter relative to pre-Multiplus loads actually matter for how ESS calculates available shore current?
• Should all AC loads ideally sit on the AC-out side to avoid this confusion, or is a split arrangement workable with the right config?
• Anyone had to tweak the maximum shore current setting manually to compensate rather than letting ESS manage it dynamically?

Running VE.Configure with the latest firmware. I did wonder if the AC input current limit assistant was conflicting with ESS but I'm not experienced enough to be sure.

Would be useful to know how others have physically wired their hook-up arrangements, especially those with mixed loads in a static off-grid building rather than a vehicle.

@SaltyGrafter the Carlo Gavazzi ET112 placement catches people out constantly. If it's sitting on the grid side before the Multiplus AC-in, it's seeing everything — your critical loads on AC-out-1 plus anything you've wired directly off the grid before the inverter.

Had almost exactly this on my static van setup. Cerbo was going mental trying to limit shore current because the meter kept reporting higher draw than the Multiplus thought it was responsible for.

The fix that sorted mine — make sure ESS Assistant is configured correctly and your grid meter is genuinely measuring only what feeds the AC-in terminal. Any loads wired upstream of that are invisible to the control loop but still counted by the meter.

What's your current ESS grid setpoint sitting at? That's usually where the gremlin hides.

@SaltyGrafter had exactly this with my shepherd's hut last year. The shore current limit thing drove me mental until I realised the Multiplus was seeing the ET112 readings and doing its nut trying to compensate for loads it thought were on the wrong side.

Check your ESS assistant settings — specifically whether you've got "prevent feedback to grid" ticked and what your grid setpoint is sat at. Mine was at 0W and causing the inverter to throttle the charger constantly.

Also double-check the VE.Configure shore current input limit matches what your supply can actually handle. Easy to overlook.

What firmware are you on? There were some ESS quirks in older versions that made this worse.

Yeah this bit me hard with my shepherd's hut build. The shore current limit thing is basically the Multiplus trying to protect whatever supply you're feeding it from — if the ET112 isn't seeing the full picture of what's being drawn, it can't do its job properly and the system gets confused about how much headroom it actually has.

Worth checking in VictronConnect whether your AC loads are configured correctly as "AC-in" vs "AC-out" loads in the ESS assistant. Got mine wrong first time round and the dynamic current limiting was all over the place.

Also — what's your input current limit set to in the Multiplus settings? If it's too conservative relative to your actual supply it'll throttle earlier than you'd expect.

Something worth adding to what @Lefty and @FellKev have covered — the shore current limit interacts differently depending on whether you've got AC loads wired to the AC-out-1 passthrough or running upstream of the Multiplus entirely.

In my garden office setup I've got a small 13A consumer unit on AC-out-1 for the "important" stuff (NAS, networking gear) and the workshop tools fed directly from the grid ahead of the inverter. The ET112 only sees grid draw, so the Multiplus correctly compensates without trying to throttle the tools it doesn't even control.

Key thing: if your shore current limit keeps tripping unnecessarily, double-check in VictronConnect what your AC input current limit is actually set to. Sometimes it survives a firmware update at a lower value than you configured. Caught me out on my Multiplus-II 12/3000 after a bulk update through the Cerbo.

Good shout from @AndyRobinson on the mode differences — worth adding that the AC-in monitor position relative to your critical loads matters enormously here too.

When I wired my garden office Multiplus-II setup, I initially had the Carlo Gavazzi EM24 on the wrong side of a sub-board and the ESS algorithm was basically flying blind on actual grid draw. Kept hitting the shore limit seemingly at random.

Double-check your EM24 is genuinely seeing all AC-in consumption — not just what's downstream of the Multiplus. VRM will show you pretty clearly if the readings look suspect. Mine was clocking impossible numbers until I sorted the CT clamp orientation (classic rookie error, done it twice now somehow 🤦).

What's your current limit actually set to in VEConfig? That might help narrow down whether it's a config issue or a metering one.