Got a similar situation in my motorhome and it's been bugging me a bit.
Running a Victron Orion-Tr Smart 30A DC-DC charger alongside a 30A mains hookup charger, feeding into a 200Ah lithium (Fogstar Drift). On paper that should be decent throughput, but in practice the lithium's never pulling what I'd expect when charging from the alternator on the move.
My installer mentioned something about the Orion being "smart" enough to protect the alternator, so it throttles back — fair enough. But I'm curious whether anyone's seen their system actually sustain max rated input for any length of time, or if it always tapers off quicker than you'd think?
Also wondering if a 50A DC-DC like the Victron Booster would make a meaningful difference on a longer run, or if you'd still hit the same throttling behaviour once things warm up.
Few questions for anyone who's been down this road:
- What's a realistic expectation for sustained charge current from a DC-DC on a 2–3 hour motorway run?
- Does alternator health/age play a big role in what you actually see?
- Anyone running dual chargers (mains + DC-DC simultaneously) — do they play nicely together or fight over the battery?
Not complaining exactly, just want to understand what "normal" looks like before I go back to the installer asking questions. Feel like the headline figures on the tin don't always match real-world use in a campervan setup.
What are others seeing?
