Annoying AC Load

Got a right head-scratcher with my setup that I reckon a few of you lot will recognise.

Running a Victron MultiPlus-II with an ET112 meter clamped on the output side, and I've got one load that's basically making my system behave like it's had too much coffee — constantly fluctuating, never settling, driving the ESS assistant absolutely mental.

The culprit? An older tumble dryer with a dodgy heating element that cycles on and off every few seconds rather than drawing a steady load. The MultiPlus keeps trying to compensate and ends up in this perpetual tug-of-war with itself. Lovely bit of kit being bullied by a 1990s Hotpoint.

Tried a few things already:

• Adjusted the ESS minimum discharge power
• Tweaked the AC input current limit
• Stared at the VRM dashboard willing it to behave

None of it's sorted it properly.

Wondering if anyone's tackled something similar — particularly whether there's a way to add a small buffer or dampen the response so the Multi stops reacting to every little spike. Some kind of averaging window in the ESS settings perhaps? Or is it just a case of admitting defeat and replacing the dryer?

Also curious whether swapping to an EM24 over the ET112 would make any meaningful difference here, or whether that's just expensive placebo territory.

Anyone else had an annoying AC load that's made their otherwise tidy setup look like it's been configured by a caffeinated squirrel? How'd you fix it? 👇

@MultiPlusFan classic case of the ET112 seeing reactive/inductive load spikes and the MultiPlus having a minor wobble trying to decide whether to assist or not — what's the actual load, a compressor fridge by any chance?

The fix that sorted mine in the motorhome was tweaking the Grid Setpoint in VE.Configure from the default 0W up to maybe +50W, gives the MultiPlus a bit of breathing room before it starts chasing its own tail on small fluctuations — Victron call it "hunting" and it's infuriating.

Also worth checking your AC input current limit isn't set suspiciously low, because the unit will throttle itself in odd ways that look like a faulty reading rather than a control loop issue.

What firmware are you on? Pre-500 builds had some genuinely sketchy ESS behaviour with clamp meters.

@MultiPlusFan had almost identical grief last winter with my motorhome setup — turned out the culprit was a cheap inverter-driven compressor fridge I'd retrofitted. The inrush was making my MultiPlus-II briefly drop into passthrough before recovering.

Fixed it two ways:

1. Soft-start capacitor wired across the compressor terminals — knocked the inrush spike down dramatically
2. Bumped the AC input current limit slightly higher in VE.Configure so the MultiPlus had more headroom before it got spooked

Worth checking your VRM portal — pull up the 30-day graph and look for those telltale vertical spikes on the AC load reading. They'll show you exactly when and how often it's happening.

What's the actual load causing you grief? Fridge, air con, pump? Makes a difference to the fix.

@MultiPlusFan my shepherds hut kettle did something similar — Victron's ESS assistant was basically playing whack-a-mole with the grid setpoint every time it kicked in 🔨

@MultiPlusFan what's the power factor on that load? Worth chucking a clamp meter with PF display on it — something like the Uni-T UT210E — because the ET112 measures real power (watts) but the MultiPlus is having to deal with the apparent power (VA). If your PF is sitting at 0.6-0.7 you could have a load drawing considerably more current than the wattage suggests.

Had this exact scenario on my narrowboat with an old compressor fridge — nameplate said 150W but it was hammering the inverter disproportionately hard on startup.

Also worth checking your MultiPlus AC input/output voltage settings in VEConfigure — if the voltage trim is slightly off, the ESS calculations go sideways and you get that hunting behaviour where it's constantly correcting. What firmware version are you on?