MPPTs do not feed into to the grid when batteries are full

[JLK]

Good day,

Can someone please help with this problem.

Current system:

2 x 5kW Multiplus Inverters in parallel

1 x SmartSolar 250/100 MPPT

1 x Smartsolar 250/85

1 x MPPT 450/100

8 x Blue Nova (5kWh) batteries

ESS set to Grid feed-in (No Limit)

1 x CERBO MK2

The first installation was in 2019 (1 MultiPlus 5kW Inverter, 1 MPPT, CCGX, 2 Blue Nova RacPower DU, 6kWp PV.) In time another Inverter was installed (in parallel), more PV Panels were installed, 2 more MPPTs installed and another 6 Blue Nova Rackpowers.

After installing more PV panels in February 2026, we installed the 450/100 MPPT to accomodate West and East facing roofs. Because of the problem with the CCGX having only 2 VE-Direct ports and not wanting to go the USB way, we installed a new CERBO GX MK2 into the system.

All firmware were updated, as well as all CERB0 and Inverter settings were updated.

What we found was that when the batteries are full from PV generation, 1 or 2 MPPTs are throttled to produce less power (sometimes zero power), and feedback into the grid is greatly reduced.

Any help with this will be much appreciated.

[lxonline (LX)]

Cap the voltage at the absorption voltage in dvcc (55v).

[JLK]

Hi LX, thanks for the prompt reply.

The Blue Nova batteries that we use locks all DVCC parameters, so I am stuck with the MPPT and VE Configure charge voltage settings.

Regards

[lxonline (LX)]

@JLK

locks all DVCC parameters

Limit charge voltage should not be. That would be unusual to say the least

[JLK]

Hi LX,

This is what I am stuck with.

[nickdb (Nick)]

Just click the limit charge voltage to on. It isn’t forced off.
I would also use the new UI, way better.

[lxonline (LX)]

It is not forced off -just touch it to toggle it on and set the voltage.

I have several systems with the DU on them.

[JLK]

Thank you Sire! I was lead to believe (by Blue Nova personnel!) it cannot be changed.

Will change the setting and see what happens.

Thanks again.