Left my boat last year in her winter storage end of September with service batteries (4x110Ah Victron AGM in parallel) fully charged. Open voltage was 13.10V. Then checked batteries end of November. Open voltage at 12.93V. Battery main switch always turned off > means no loads at all.
Today I made a short visit to my boat to check again. According to the battery display (has its own shunt and measured at the battery pole) voltage was down to 12,71V. Confirmed measurement with a DMM and the BMV 702 (also with its own shunt). Battery temperature at 6.2°C.
Decided to put shore power on to charge with the MultiPlus. Charge current in bulk was around 40A and decreasing. Charger went into absorption phase about 15 minutes later at 14.7V. Now I would expect the absorption phase to last for at least 2 hours if not longer. But charger decided to switch into float in less than 30 minutes while still charging at about 13A. The second before switching into float, current was at 17A. That doesn't look ok to me or is it normal that absorption only lasts for that short duration while battery is still sucking lots of amps?
Second problem as you can see from the image is float voltage. It stays at 14.08V (again confirmed with a DMM). Float voltage is set to 13.80V and max charge current fixed at 40A with VE.Configure when I bought it as a new device. And so far for the last two seasons it has worked simply fine. No issues at all. How come that float voltage gets that high and why is the absorption phase so short?
Hopefully there's someone who can enlighten me.