Victron Orion 30A keeps cutting out when engine's warm — anyone else had this?

Had exactly this with my Orion 30A about 18 months ago. Turned out to be a thermal shutdown issue — the unit was mounted inside a cupboard with basically zero airflow. Moved it to a spot with decent ventilation and the problem went away almost immediately.

Worth checking a few things:

• Ambient temp near the unit — these things run hot when the engine's been going a while and the alternator is pushing hard
• Input voltage dipping — some modern smart alternators back off voltage when warm, which can confuse the Orion if it drops below the threshold
• Firmware — sounds boring but there were some older firmware versions with dodgy cutout behaviour

The smart alternator thing is a common culprit tbh. If you've got a newer van (anything post ~2015 really), the Orion XS with adaptive algorithm handles it a lot better than the older units. Might be worth connecting it up via VictronConnect and watching the live data while it's running — you'll see pretty quickly if it's a voltage drop causing the shutdown or a thermal event.

What vehicle are you running it in? And is the Orion mounted somewhere it can breathe properly?

Others on here probably have more specific experience with certain engine types — be good to hear if anyone's seen this on Ford Transits specifically as they seem to crop up a lot in these threads.

@CamperEwan worth checking the input voltage drop as well — when the engine's warm and the alternator's been running a while, if your cable run is long or undersized you can get enough voltage sag to trip the low-voltage cutoff, which looks exactly like thermal shutdown from the outside.

Had something similar on my garden office setup. Turned out my 6mm² cable over a 4m run was marginal under load. Went to 10mm² and the dropouts stopped completely.

Easy way to check: stick a multimeter on the input terminals during a cutout and see what voltage you're actually getting there versus at the battery.

Great shout from both of you. One thing I'd add — have you checked your input wiring gauge? I had a similar intermittent cutout on mine and it turned out the 6mm² cable I'd used was marginal for a 30A unit over the run length I had. Under load with a warm engine, the voltage drop was just enough to nudge it below the low-voltage cutoff threshold.

Worth grabbing a multimeter and checking voltage directly at the Orion's input terminals while it's actually running — not just at the battery. If you're seeing more than about 0.5V drop across the wiring, that's your culprit. Upping to 10mm² sorted it completely for me. Dead simple fix once you identify it.

Been through something similar with my cabin setup — ended up being a combination of things rather than one single cause.

Worth checking the temperature compensation settings in VictronConnect if you haven't already. Mine was set too aggressively and it was basically throttling itself down once things got warm under load.

Also double-check your ground connections. A marginal earth that's fine cold can cause all sorts of odd behaviour once everything's expanded slightly with heat. Took me ages to track that one down.

If you're running the Orion in non-isolated mode, make sure the shared negative is properly sorted too — that tripped me up early on.

Had mine tucked behind the galley on my narrowboat doing exactly the same — @CamperEwan and @AlanPearce have nailed the usual suspects, but worth adding: check your engine bay earth loop as well, because a dodgy chassis earth gets significantly worse when everything expands with heat, and the Orion will interpret that voltage instability as an input fault and shut itself down rather than admit it's having an existential crisis.

Grab a multimeter and compare voltage at the Orion terminals versus directly at the alternator when warm — any meaningful difference points straight at your wiring or earth, not the unit itself. Victron's own app logs are brilliant for catching exactly when it trips if you've got Bluetooth monitoring enabled.

Interesting thread — had this exact drama fitting out my shepherd's hut build last spring.

Mine was mounted vertically on a wooden panel and still kept tripping. Turned out the input voltage was sagging under load because my engine bay fuse holder had developed a dodgy connection — adding maybe 0.3–0.4V of resistance drop. Victron's Orion is pretty fussy about that input threshold.

Grabbed a Klein multimeter and measured voltage at the unit's terminals rather than at the battery. Night and day difference from what I expected.

Worth doing @CamperEwan — rule out the obvious thermal stuff first as you've done, but if that's sorted, check actual terminal voltage under load rather than assuming your wiring's clean. A proper inline ANL fuse holder from Fogstar sorted the dodgy connection on mine and it's been solid ever since.