Been scratching my head with this for a few weeks now. Running a MultiPlus 24/2000 with a 200Ah lithium bank (4x 50Ah Winston cells) and a Cerbo GX. Everything's talking to each other fine via VE.Bus, SOC is reading correctly, all that — but the charger keeps dropping into float at around 80–85% SOC when I've got a decent load on (kettle, microwave in short bursts, that kind of thing). Feels like it's getting confused between charging and supplying the load at the same time.
I've had a poke around in VEConfigure and the absorption voltage is set to 28.4V with a 2-hour fixed absorption time. Wondering if the issue is that under load the voltage is sagging enough that the unit thinks absorption is done and just gives up early. Current limit on the AC input is set to 16A (I'm on a 16A hook-up at a storage site), so it's not like it's got loads of headroom to play with.
Has anyone tuned the tail current / absorption end settings on a similar setup? I know the MultiPlus lets you set an absorption end current rather than relying purely on time or voltage, but I'm not sure what a sensible figure would be for a 200Ah lithium pack. Any ideas welcome — getting a bit frustrated with only ever getting a partial charge on grey days when I need every bit of capacity I can get.