Anyone else running Victron Multiplus on a motorhome with shore power complications?

Picked up a Multiplus 12/3000/120 for the motorhome build I'm doing alongside my garden office setup, and I'm running into something a bit annoying. When I connect to site hookup (the typical 16A blue connector on most UK sites), the unit keeps throwing an overload warning even though I'm nowhere near the 3000W inverter limit. Think it might be the input current assist settings but not 100% sure.

Running 3x 200Ah Fogstar Drift LiFePO4 in parallel, 600Ah total, paired with a 40A Victron SmartSolar MPPT. Shore power is feeding into the Multiplus as AC-in, and I've got the input current limit set to 16A in VictronConnect — which should be fine for a standard UK hookup post. The overload trips seem to happen when the compressor fridge and the kettle kick on at the same time, both drawing from the inverter side rather than passthrough.

Has anyone configured the PowerAssist feature to handle this kind of spike? I can see the option in VictronConnect but I'm not sure what value to set for the AC input current limit to stop it trying to pull more than the hookup post can deliver. Would really appreciate hearing from anyone who's dialled this in on a similar setup — especially on smaller 10A site hookups you sometimes get on farm sites.

@NeilJackson had almost exactly this with my Camper Van build last spring. The Multiplus was doing that thing where it refuses to accept shore power because the site hookup is slightly outside its input voltage tolerance — older campsites especially can have quite wobbly grid quality.

Worth digging into VEConfigure and loosening the AC input low voltage and AC input high frequency thresholds. Mine was rejecting anything below 207V and some rural CL sites were serving up 198V on a bad day.

Also check your weak AC setting is enabled — absolute game changer for dodgy hookups. Essentially tells the Multiplus to be less fussy about waveform quality.

Victron's own community forum has a brilliant thread on exactly this if you search "shore power rejection campsite" — saved me hours of head-scratching.

Been through this exact headache on my motorhome build. The Multiplus has an input current limit setting in VE.Configure that defaults higher than most UK site hookups can actually deliver cleanly.

Worth checking your shore power input sensitivity too — some sites (particularly older caravan parks) deliver pretty rough AC that the Multiplus doesn't love. I dropped my input voltage range to accept down to about 180V and it stopped the relay clicking drama entirely.

Also, if you're not already using VE.Bus Smart Dongle or a direct USB interface to tweak these settings, it's genuinely worth it rather than guessing. The stock configuration assumes a much cleaner supply than you'll typically find on a 16A blue hookup at a busy site on a Bank Holiday weekend.

Classic site hookup issue. Worth checking your AC input current limit is set correctly in VE.Configure, but also look at the PowerControl and PowerAssist settings — these are what actually manage the balance between shore power and inverter output.

On mine (garden office setup rather than motorhome but same Multiplus behaviour), I also had to enable weak AC input mode. Some site hookups have genuinely dodgy waveforms that confuse the unit.

One more thing to check — the transfer switch relay settings. If the Multiplus keeps dropping shore and switching to inverter briefly, it might be rejecting the site supply as out-of-spec rather than a settings issue.

Victron's VE.Configure tool gives you full control over all of this. Worth grabbing if you haven't already.