What is the purpose of "Enable AC Charge Upper % Limit"

I'm trying to get my head round charge limits. In particular "Enable AC Charge Upper % Limit". I have searched to forum, and there have been posts referencing this switch, but no clear answer. Can anyone shed some light on the purpose of this switch and its associated percentage value?

My problem was that with reduced sun hours, I had increased the overnight "Charge to.." percentage in the app, but this had no effect. The battery did not charge to the requested percentage.

A quick review of Inverter settings via the portal revealed that increased charge percentage was correctly set in the "Charge 1 Settings". However, under General -> Enable/Disable, "Enable AC Charge Upper % Limit" was enabled and the associated charge level percentage was set to a lower value. This value was taking precendence.

Thinking about it, I was not surprised. A global limit seemed to be overiding the charge time slot settings.

So what is the purpose of "Enable AC Charge Upper % Limit"? How should it be used?

Thanks for reading, and thanks in advance for any words of wisdom.

I’m away at the moment so relying on memory but it used to be called winter mode at one point.
If it is not enabled, then if you have an AC charge time set it will simply charge for the entirety of the period until either time runs out or your battery is at 100%
If it is enabled, then the system will stop once the target value is hit and system will simply wait until end of the charge period.

Note - this was how it worked on Gen 1, I’m aware of all manner of Fw changes to newer kit so they may well act differently. There was also a bug at some point where the battery oscillated between charge and discharge once target % was hit. Think that got solved but equally if you changed the value up/down 1% it normally stopped doing it, weirdly.

hoggy And on newer kit with multiple charging slots, I think it's redundant anyway: the limit it controls is not used by the inverter. GE have recently fixed the bug where the app/portal were adjusting wrong limit, and they now adjust the limit associated with charging slot #1

I don't think it affects the numbered charging slot limits. (It was already redundant really - what's wrong with just setting the limit to 100% if you want 100%)

I also got caught out with the same thing until I twigged that there was a global limit over-riding it!

I use this setting to charge my battery to a maximum of 60% overnight when my tariff is at its lowest. I set it at 60% as I get enough from the PV panels to charge battery to 100% during daylight hours. As the days get shorter and lower levels of PV generation I will probably adjust the 60% to a higher charge % during low tariff periods. Make sense to charge at 12p/kWh and discharge to home when energy provider units are 26p/kWh.
On a good day when my home usage does not deplete battery lower than 60% there is no overnight charge required.

hoggy There was also a bug at some point where the battery oscillated between charge and discharge once target % was hit. Think that got solved

Its still there on the "fast response" f/w. It doesn't happen unless you set things via the portal/app IME.