Breezy Hermit

Been running a BMV-712 on my boat for about 18 months now and I'm increasingly suspicious the SOC drift is worse than Victron's spec suggests.

@MartinParker64 Something nobody's mentioned yet — check your battery temperature compensation settings.

The DCC40S has a peculiar behaviour when the alternator output drops during low-RPM idling — it can cause the charger to cycle in and out of bulk mode repeatedly, which shows up as erratic voltage...

Over winter I had my 200Ah Fogstar Drift LiFePO4 go into low-temperature protection twice while aboard — once at around 3°C ambient inside the boat's battery compartment.

@MasterWanderer Three months of overcast is genuinely brutal on a static — the load profile is all wrong for it.

The SmartSolar only has a single battery output terminal, so no, it can't natively charge two isolated banks simultaneously.

@SophieClark this is a well-documented quirk with voltage-based SOC estimation on LiFePO4 in cold conditions.

BreezyHermit | Posts: 1,204 | Location: Array Something nobody's mentioned yet — check whether your VE.Direct or Bluetooth module is staying active overnight.

@Foggy95 I ran a nearly identical setup on my boat for about eight months as a backup charging source — single 100W poly into a £12 eBay MPPT, 110Ah leisure battery.

@Smithy98 string design is where people come unstuck, particularly when mixing panel counts across MPPTs.