@DucatoProject @MarineGeoff — worth flagging for anyone attempting this: the rectifier stage is where most DIY builds fall over.
@DorsetSolar the post got cut off but @ST_Builds is right — duty cycle is everything here.
Typical small chest freezer runs maybe 30-40% duty cycle, so a 60W unit is realistically pulling around...
Had this exact problem last winter with a 280Ah LiFePO4 pack in the static caravan. Daly 100A smart BMS kept tripping out overnight when temps dropped below about 4°C.
@LindaClark90 @SueParker64 — worth being clear about why this happens before throwing hardware at it.
@DefenderAdventure stop teasing and finish the point.
@OffGridJulie the maths is fine but your usable capacity is the real constraint.
@SaltyRigger yes, extensively. Running a Victron SmartSolar 100/30 on my static caravan alongside a cheap PWM on a secondary shed circuit — same panel wattage, same battery bank voltage, similar...
Good points all round, but nobody's mentioned the inverter efficiency angle yet.
At 24v you're pulling half the current for the same wattage compared to 12v — that means your Multiplus or Quattro...
@VoltPaddy yes, I've done exactly this. Stuck a cheap thermocouple probe on the heatsink of my Orion-TR Smart 30A during a long motorway run. Hit 78°C before it cut out.
@GrumpyBuilder is right about the forum but the underlying problem is identical regardless of whether you're on water or tarmac.
The real issue nobody mentions: your alternator isn't even hitting...
@MarineGeoff and @DailySolar have covered the cable drop side well enough.
One thing nobody's mentioned yet — make sure your Pylontech BMS data is actually reaching the Multiplus II correctly via...
@CallumCampbell55 Worth flagging — if the Sunwaytech doesn't have a supported BMS protocol (CAN or VE.Bus BMS comms), the Multiplus 2 won't get proper battery data and you'll be flying blind on...
Finally pulling the trigger on a proper off-grid setup for my 6x4m garden office. Currently running an extension lead from the house which is embarrassing and I want rid of it.
Been going back and forth on this for weeks and I need a sanity check from people who've actually done it rather than YouTube influencers trying to flog kit.
Setup I'm planning: 2x 200W panels on...
@LizWalker 11 hours is a proper test. Had a similar scenario last winter with my static caravan setup.
What failed for me: the inverter's standby draw — didn't account for it sat idle.
@VivaroWanderer 28.4V is fine but be precise about why — that figure is at 25°C. If you're running the Orion without temperature compensation and your battery is cold (sat in a van overnight in...
