Been a strange few weeks here. Running a 400W panel setup (2x 200W Victron in series) into a SmartSolar 100/30, feeding a 200Ah lithium. During the cold weather last week — we're talking overnight lows around -4°C here in the Peak District — the controller was reporting some genuinely odd numbers. Saw the VOC spike to nearly 48V at dawn which fair enough, cold panels do that, but the absorption voltage kept cutting out early and the app was throwing state-of-charge figures that seemed completely detached from reality.
What's got me curious is whether the Bluetooth readings on the VictronConnect app lag behind what's actually happening, or if the controller itself is recalibrating somehow in those temps. The battery's a 12V 200Ah LiFePO4 from Fogstar — relatively new, only about 8 months old — and its own BMS readout disagreed with the Victron figures by nearly 18% at one point.
Has anyone else had their monitoring go a bit sideways in the cold? Wondering if I need to adjust any of the charge profile settings manually for winter, or if there's something worth checking physically on the install. The cable runs are about 4 metres from controller to battery if that makes any difference.
