SoC drops about 1% with each recharge cycle

[pwfarnell]

Some further thoughts as the installation of the Multiplus has started this.

1. Is everything wired correctly to the shunt, do either of the MPPT or Multiplus negatives connect directly to the battery. See linked FAQ.
2. Are you reading SOC though something like a GX device (Cerbo e tc), if so is the SmartShunt set as the battery monitor or the Multiplus. On the GX check Settings / System Setup / Batteries / Battery Monitor.

As noted previously, to help diagnose this, please post a screenshot of the SmartShunt trend for battery current and battery voltage as the MPPT goes to float. This should cover the last 30 minutes in absorption through to 5 minutes or so after float. Also your current SmartShunt settings.

Shunt / battery monitor not reading the correct SOC/ Amps, missing solar, decreasing daily or other misreading problems

This topic covers the SOC / Amps reported by BMV battery monitors, SmartShunts, Lynx BMSs and Lynx Shunts and will just be called shunt below. It is also assumed that the shunt is monitoring the domestic / house / cabin battery bank and not engine start / bow thruster / winch / caravan mover battery banks. The problems may be one or more of the following The SOC decreases daily despite the solar charger or other charger(s) working. The SOC increasing when discharging and falling when charging…