Rogue MPPT, 490W and charging mysteries

Almot wrote:

It stays in ABS at 14.4 (setpoint 14.7) - fine, controller just does what the battery can do, healthier AGM behave more normal. Current on starter batt dropped gradually to 0.5 A, setpoint FLOTR=1A - Rogue doesn't allow setting less than 1A, but here is what looks odd:
1) darn batt won't go to float. The batt is to blame, I agree.
2) Controller hates this junk, and is "steping up MPPT" - some sweep mode that it does once in a while in ABS, but it does this sweep every few minutes. He doesn't do this to healthier AGM (unless light conditions change abruptly), so this is must be how Rogue should work, i.e. no problems with Rogue.

The controller won't transition to float based on battery current if it's unable to hold the battery voltage at the absorb setpoint (as appears to be the case with that old battery). It should transition when the timer expires, though, regardless of current.

You may see a little blip in the charging current and PV voltage as the battery temperature varies up or down. It's normal because when the temperature changes, the setpoints change a little too, so the controller is trying to adjust for it. It'll be more obvious with very light loads. The controller may also attempt to see if there's a new MPP during absorb or float if circumstances cause it to bump up against the last measured MPP, but I don't think that's what you're seeing.

3*100 AH AGMs are back in float. Yes, they go to 14-something as soon as Rogue wakes up or restarts after panels had been disconnected and re-connected. Starts from bulk-MPPT at sunrise, when sun clears the mountains V rises to ABS 14.7 as it should (plus cooler morning temp correction 0.2V or so), then goes into ABS for a second or two, then to Float ~2A after 2 days of floating.

That's very common: to have batteries transition almost immediately to float the following day if they were floating a lot the day before. Takes very little current to get the battery voltage to rise in those cases.