Had this on my boat last spring. Turned out my Fogstar Drift cells were sitting at a dodgy state of charge — the BMS was reporting higher than actual because I hadn't done a proper full charge...
@OakSoul ran something similar on my boat for a bit. One thing nobody's mentioned yet — make sure your Cyrix-CT 120 is seeing the right current threshold to actually trigger.
Got a Fogstar Drift 200Ah sitting in my cabin and wondering if it'll cope with running a small chest freezer overnight without completely tanking the battery.
The freezer is a Subcold Pro 35 —...
Had this exact issue on my boat last summer. Turned out to be thermal cutout — the Orion was mounted flat against a wooden bulkhead with basically no airflow.
Ha, four of us now apparently. Welcome to the world's most suspenseful battery thread.
@RustyTinker while we're all waiting — 11.8v overnight with zero load does sound like a dud cell to me.
Had a similar headache with my Cerbo GX last month. Was testing a cheap EVCS integration and it half-worked, then I removed it — but the ghost device just sat there on VRM like it owned the place.
Winter's the real test tbh. I've got a similar-ish setup on my cabin and December/January can be rough — panels barely seeing 2-3 hours of usable sun some days up here.
The 200Ah Drift is a decent...
Were they exposed to freezing temps at any point? My cabin setup had similar issues one winter — turned out the cells had been charged while still cold.
Been running a small cabin setup through two winters now — 300Ah Fogstar drift cells, 600W panels south-facing as steep as I could get away with.
Biggest thing I'd say: generator backup isn't...
in Q&A
4 months ago
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Mine drops out sometimes when there's a lot of BT devices nearby — boat marina is a nightmare for it.
Running something similar on the cabin — single 100W panel into a budget MPPT I grabbed ages ago.
Main thing I'd watch is the absorption voltage setting.
Been running something similar on the cabin — Fogstar Drift 100Ah, Victron MPPT, couple of panels. Added a small inverter genny last autumn as backup.
Main thing I'd add that nobody's mentioned...
Had this exact issue on my boat last winter. The JK default low temp cutoff is set pretty conservatively from the factory — worth connecting via the app and checking what yours is actually set to.
Fogstar_Fan | ⛵ 312 posts
Had similar on my boat with a 12V bank. Ended up going 48V eventually and the difference is night and day — cables stay cool, inverter barely blinks under load.
One thing...
@FellGraham honestly that second fridge thing hit close to home. Got my Fogstar cells sorted on the cabin and suddenly I'm running a chest freezer "because I can now"
Hadn't even...
