I have a Victron M.P.P.T 100|30 with 140W panel on the P.V side. Collectively they are charging a 600Ah Victron Li.Fe.Po Smart Battery Bank installed on a boat, with no 120VAC shore power taken on. The M.P.P.T is configured for Li.Fe.Po and is setup for adaptive charge profile.
The issue I am seeing that concerns me is that the absorption time each day is approximately 2hrs even though the batteries never drop below 13.3V during the evening. The vessel is unattended and has no loads and so never drops below 13.3V and 99% SoC. This is obviously outside the 2hrs per month recommendation for lightly loaded system, as stated in the Victron Smart Battery Manual. I also see that the charge current off the M.P.P.T during absorption is approximately 1.8A when in Absorption, with approximately 1.3A of that value going into the bank as reported by the B.M.V.
Question: Why is the M.P.P.T holding itself into Absorption that long and how do I stop this behavior. According to the manual, if the battery voltage doesn’t drop below 12.6V the maximum absorption time should be 1hr (x1/6 Multiplier). So that’s no happening to begin with. And the tail current is 1.3A which is way below the usual 2% tail current switch most chargers have for switch to float.
If somebody can please make some recommendations I’d appreciate it? Thanks in advance for your help.
Matt