Opportunity loads and load shedding in an inverter overload scenareo

Been thinking about this a lot lately since upgrading my shepherd's hut setup, and I reckon it's worth a proper discussion here.

The scenario I keep coming back to: you've got a reasonably sized inverter — say a Multiplus II 3000 or 5000VA — and over time the load profile creeps up. What started as lights and a heating pump becomes lights, heating pump, and an immersion heater on a relay, and someone plugging in an induction hob. Suddenly you're nudging the inverter's limits.

So the question is: how are you lot actually managing opportunity loads versus essential loads when the inverter's being pushed?

My current thinking for the hut is running Node-RED through a Cerbo GX to shed non-critical loads when AC output hits a threshold — immersion being the obvious first casualty. But I'm wondering whether others are doing this more elegantly, maybe with the ESS assistant or some custom relay logic.

The other angle is whether it's better to properly right-size from the start rather than bolt on load shedding as an afterthought. My hut is small enough that I can be disciplined about it manually, but I imagine a larger cabin or farmhouse setup gets complicated fast.

A few things I'd love to hear from people:

• Are you using assistants in VEConfig to handle this, or external automation?
• Has anyone had an inverter actually trip under overload and what caused it?
• Is load shedding a reasonable long-term strategy or just a sticking plaster?

Feels like one of those topics that gets glossed over in the initial design phase and then becomes a real headache later.

Great topic @LynnCrane - looking forward to seeing where this goes once you finish the thought!

But I'll jump in with what I think you're heading towards, since it's something I've wrestled with on my marsh setup.

The key thing I've found with opportunity loads is having a proper priority hierarchy before you hit overload territory, not scrambling reactively when the inverter's already screaming. My immersion heater is the first thing on the chopping block - it's pure thermal storage, so shedding it mid-cycle costs you almost nothing in practice.

The trickier question is non-interruptible loads like fridges. I use a small contactor arrangement with a basic voltage monitor to buy the inverter breathing room without cutting essentials.

What inverter are you running? Some handle overload transients far more gracefully than others - that changes the whole calculus considerably.

Typical @LynnCrane leaving us on a cliff-hanger — my Victron MultiPlus does the same thing, cuts out right before the good bit.