Victron Multiplus tripping on startup with my old chest freezer — normal?

Had exactly this with an old Larder fridge I picked up years back. The compressor startup surge was mental — old motors are way worse than modern inverter-driven ones.

Few things worth checking:

• PowerAssist settings in VE.Configure — sometimes tweaking the AC input current limit helps
• Dynamic Current Limiter — enable it if you haven't, it helps the Multiplus cope with sudden load spikes
• Transfer switch delay — might be worth looking at

My Multiplus 2 (48v/3000) tripped constantly on an old chest freezer until I bumped the LOM detection setting down. Made a massive difference.

Also worth knowing — older compressors can pull 5-7x their running wattage on startup. A fridge that runs at 100w might spike to 600-700w for half a second. The Multiplus should handle this with its overload headroom, but the age of the unit and your battery setup matters a lot.

What's your battery bank? If you're on lead-acid with any age on them, internal resistance could be the hidden culprit — voltage sags under surge load and the Multiplus panics. Switched to Fogstar Drift LiFePO4 last year and startup issues like this basically vanished overnight.

Worth posting your VE.Configure screenshots if you can — someone here will spot something daft in the settings. Had mine looked at in a thread ages ago and it turned out I had a setting completely wrong from a YouTube tutorial. Embarrassing but sorted it fast.

Anyone else had this with older appliances specifically? Curious whether it's a common pattern with pre-inverter-compressor gear.

@FormerMachanic74 raises a solid point about old motors — been through exactly this with my van conversion.

What sorted it for me was digging into the Multiplus settings via VictronConnect and bumping up the PowerAssist threshold slightly. The inverter has a built-in inrush tolerance that's quite conservative out of the box.

Also worth trying:

• A soft starter relay wired into the compressor circuit — cheap fix, massive difference
• Check your battery bank can actually deliver the surge current; I was running Fogstar Drift cells and even they momentarily sagged under an old compressor startup
• Lower the AC input current limit carefully if you're on shore power — counterintuitive but it forces the Multiplus to manage peaks differently

Old chest freezers are brilliant for van life efficiency-wise once you crack the startup issue. Don't bin it just yet.

Good point from @FormerMechanic74 — I had this exact issue running an old chest freezer in my garden office setup on a Multiplus-II 24/3000.

What actually fixed it for me was enabling the PowerAssist feature in VictronConnect and bumping up the AC input current limit slightly. The Multiplus was struggling because it was trying to protect itself from that initial compressor surge.

Also worth checking your transfer switch settings — if the unit thinks it's got weak grid input it behaves oddly on startup loads.

Older compressors can draw 5-6x their running current for that first half-second. Modern inverter-driven fridges barely flinch by comparison. If the freezer is genuinely old, honestly might be worth weighing up whether it's worth keeping versus a newer unit that'll also be far more efficient on your battery bank.

@FormerMechanic74 makes a fair point about legacy compressors, but worth being precise about why this happens — old single-phase induction motors can draw 6–8× running current at startup (locked-rotor current), sometimes for 200–400ms. The Multiplus's overcurrent protection sees this as a fault condition.

Before assuming the inverter is undersized, check your PowerControl and PowerAssist settings in VictronConnect — the transfer switch threshold may be set too conservatively. Also worth enabling the weak AC input setting if you're on a generator.

Longer-term, a soft-starter module (Microstart or similar) wired inline with the compressor dramatically reduces inrush. I fitted one to my cabin freezer and the Multiplus 2000VA handles it without flinching now — previously it was tripping on a 3000VA unit.

Also confirm your DC cabling is adequately sized; voltage sag under surge load can compound the problem considerably.

Something nobody's mentioned yet — soft start settings in the Victron MultiPlus itself. Buried in VE.Configure, there's a transfer switch delay and AC input current limit you can tweak. Took me an embarrassingly long time to find it when my own van's ancient borrowed chest freezer was making the MultiPlus throw a wobbly every single morning at 3am. Every. Single. Morning. 🙃

Also worth checking: is your battery bank big enough to handle that surge without the voltage sagging so badly the inverter panics? Old compressors can pull 6-8x running current on startup. My Fogstar Drift cells handled it fine once I'd added a second battery — before that, the MultiPlus was basically having a small existential crisis daily.

Short version: it's fixable, don't bin the freezer just yet!