MPPT stays in Bulk, not going into absorption nor float

DIY
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Hi, I have a full 12 volts Victron System in a Van. Multiplus II, Cerbo GX with touch display , BMS-2, Orion Dc-Dc for controlling output DC voltage, battery protect, SmartShunt, 2X 12V 330 AH Victron SmartLithium batteries and a MPPT 100/50 to control PV input from external solar panel. PV is connected to the MPPT and it is charging the batteries, but even when the Touch Display shows the batteires at 100% SOC since a few days in a row (without any load connected to the system during these days, so no significant drain to the batterie, only the Victron equipment above), MPPT is not going into absorption nor float, always stays in bulk mode. Batteries are going into absorption and float when charged from grid connected to the Multiplus though, but not when charged from the MPPT. Parameters in the MPPT are Absorption Voltage to 14.2V, Float voltage to 13.5V (default parameters for the SmartLithium Batteries Setting, and as per batteries manual, 13.5 is the specified Float voltage, but I can’t find the specified absorption voltage for the 330AH Victron LiFePo4 battery). When looking at the MPPT details in the Victron Connect app, on the PV side I see voltage (35-40 volts, which is OK for the PV) as well as current, again in spec with the panel specifications, and on the batteries side I see around 13.58 volts and the equivalent PV current for this voltage at 100% SOC. But MPPT always stays in « Bulk ». I don’t see why the MPPT would not go into absorption and float afterwards but keeps staying in Bulk. Any thoughts?

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14.2V is the correct absorption voltage for the Smart Lithium batteries.

The MPPT will be under DVCC control and in this case only shows bulk, mine does this under DVCC control. If it was in true bulk it would not have reduced to the float setting of 13.5V.

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Thanks so much! This is interesting, since the installer has not checked the DVCC option in the GX parameters. DVCC is currently unchecked. So am I OK to understand that the Cerbo cannot be the one controlling the MPPT in this case?

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If you have a look in VictronConnect and the SCC State says “bulk” (or Absorb or Float) then the SCC is definitely not being controlled by the GX - if it were, it would be “External Control”.

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If the voltage doesn’t reach 14.2v it won’t go into absorption. As float is 13.5v, 13.58v is above that means it’s still trying to get to 14.2v.
I get this on odd days even when it’s sunny.

Screenshot_20250515-072651
Screenshot_20250515-0726511080Ă—2400 196 KB

As you can see the voltage even after a good few hours of bulk just hasn’t got much above 13.6v