Victron Orion 30A keeps cutting out after 20 mins on long drives - any ideas?

Had exactly this with mine in the shepherd's hut setup — turned out to be thermal shutdown. The Orion 30A runs hot and if it's in an enclosed space without airflow it'll cut out to protect itself.

Few things worth checking:

• Mounting position — it needs to be vertical with the fins able to breathe. Flat against a surface kills it
• Ambient temp — under a seat or in a closed cabinet is a nightmare in summer
• Cable sizing — undersized cables create resistance which makes it work harder and run hotter

Also worth checking the input voltage via the Victron Connect app during a run if you can. Some vehicles see voltage drop on longer journeys when the alternator is working hard, and the Orion can get confused and disconnect if it dips below the threshold you've set.

What's your low voltage cutoff set to? Default is quite conservative IIRC.

Mine's been solid once I remounted it with a 50mm gap around all sides and added a small 12v fan nearby. Touch wood, no issues since.

What vehicle and what's the install look like? Might help narrow it down. Anyone else had similar?

@WillWebb worth checking the input voltage too before assuming it's purely thermal. If the alternator voltage is dropping under load on long runs — particularly on older vehicles or those with smart alternators — the Orion can interpret that as an undervoltage condition and shut down. Looks identical to thermal shutdown from the outside.

Had this exact head-scratcher on my boat install. Turned out the engine bay wiring was undersized for a 30A draw over distance, so voltage at the Orion terminals was sagging badly. Bumped the cable up to 10mm² and the problem disappeared entirely.

Worth logging the input voltage with the Victron Connect app during a drive if you can — takes the guesswork out of it completely. Thermal and undervoltage are both plausible culprits here.

Good points from both @WillWebb and @DODGuy. One thing neither has mentioned yet — have you checked whether the engine management system is deliberately reducing alternator output after a set period? Some modern vehicles with smart alternators drop voltage significantly once the starter battery is deemed "full," which can cause the Orion to see input voltage fall below its threshold and shut down.

Worth logging your input voltage over a full journey with a Victron BMV or even just a cheap voltmeter before assuming it's thermal.

Also — is yours the isolated or non-isolated version? The isolated variant does run noticeably warmer in my experience. If it's in a confined space, even a small 12v computer fan on a timer can make a meaningful difference.

What vehicle is it in?

Adding to what @ExFirefighter is getting at — if it's an older vehicle with a smart alternator, the Orion-Tr Smart has a specific algorithm to handle that, but it can still behave oddly depending on how you've configured the engine detection settings in VictronConnect. Worth checking whether you've got it set to "alternator" or "BMS" mode, and also have a look at your input voltage lockout thresholds. Sometimes people set these a touch too conservatively and the unit shuts down when the alternator voltage dips slightly under load.

Also, 20 minutes is quite a consistent interval — that regularity does lean towards thermal rather than something intermittent. If you can grab the history data from VictronConnect straight after it trips, it'll tell you whether it was a temperature fault or an input voltage issue. Takes the guesswork out of it completely.

Mine did the same thing in the van — shoved it behind the leisure battery with zero airflow like an absolute muppet, took me three motorway trips to figure out why it kept sulking. 🔥

@Alan1992 makes a solid point on smart alternators, but also worth checking your cable runs — undersized wiring causes voltage drop which can trigger the low-voltage cutoff and looks identical to a thermal fault. Victron's own wiring calc tool will tell you if you've gone too thin over a long run.

Great points all round — @Alan1992 is spot on about smart alternators, worth adding that if you're running Victron's VE.Smart networking, you can actually monitor the Orion's temperature in real-time via the VictronConnect app. That'll confirm pretty quickly whether it's thermal shutdown or something else entirely.

On my boat install I bolted mine to an aluminium plate that's thermally bonded to the hull — acts as a passive heatsink and the thing runs noticeably cooler. In a van or hut context, even a small 12V fan triggered off the same ignition feed makes a massive difference. The Orion 30A dissipates roughly 25-30W as heat under full load — that's not trivial in a sealed compartment.

Also worth checking your input cable sizing — undersized wire creates resistance, resistance creates heat, and that thermal load compounds what the unit's already generating internally.