FoxESS Community - Owners & Installers Forum

We had 16.4kWh of Cube batteries installed last September and have topped them up between 20:30 and 00:30 every day during our Octopus Go Faster off-peak as our winter solar output was insufficient.

Yesterday, for the first time, solar filled the batteries and we exported a little. So how do I reduce the top-up to take account of the increasing solar production?

If I've understood correctly, reducing the length of the charging time will have the batteries discharging into the house during the balance of the off-peak and so have to be charged again with the usual round trip waste.

I would prefer it if I didn't have to change settings every day!

I might be wrong but I can’t currently see a way to do this without checking and altering daily to suit, maybe in a future update fox will introduce weather monitoring into the app but I wouldn’t hold my breath.

digital wrote: ↑Wed Feb 08, 2023 11:48 am We had 16.4kWh of Cube batteries installed last September and have topped them up between 20:30 and 00:30 every day during our Octopus Go Faster off-peak as our winter solar output was insufficient.

Yesterday, for the first time, solar filled the batteries and we exported a little. So how do I reduce the top-up to take account of the increasing solar production?

If I've understood correctly, reducing the length of the charging time will have the batteries discharging into the house during the balance of the off-peak and so have to be charged again with the usual round trip waste.

I would prefer it if I didn't have to change settings every day!

There are two options to do what you want, this first can be done at the app and is to reduce your charge time but as you say you would then discharge for the balance of the period - because your low tariff goes over midnight it is more difficult but you could set the first period to start later and the second period covering 12:00 to 12:30 to enable force charge only (charge from grid off) - and that would limit the amount of charge put in and for the last half hour the battery wouldn't charge or discharge either.

The second option can't be done on the app, it has to be done in inverter settings.
There is a setting called Maximum SoC, this limits the maximum amount the battery can be charged for off grid, but allows it to fully charge off solar - it's more fiddly and you have to be at the inverter panel to change the setting, it can be found here.

Thanks, both: appreciated!

It can be accessed via the mobile app or Ess Cloud if your account is setup as an installer account rather than a user account. But if your installer has used their account to access your inverter, you'll have to ask them to release it and they'll then lose access so may not allow this.