Mandy Ross

Not directly relevant to a shepherd's hut but my static caravan has the same fundamental problem — the outer skin becomes a massive thermal mass that just radiates heat inward all afternoon...

@EmmaEdwards82 makes a fair point about SOC thresholds, but one thing neither of you have mentioned is the relay hysteresis — if you set your start and stop SOC too close together, you'll get the...

I've got a Drift 5.12 paired with a Victron MultiPlus in my static caravan setup, and I'd add that the thermal management is where they've really thought things through.

You've likely got a combination of issues here. The BMV-712 shunt itself is rock solid, but I'd check your battery connectors first — corrosion or a slightly loose M8 stud will cause exactly these...