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  • 'Don't use battery during off peak' setting not working

Good morning @admin
Firstly, thanks for fixing the 100% charge rate issue; I tried it out last night.
In the period following the charge, my immersion heater started up and was drawing from the battery at full rate for 10 mins, then the grid topped the battery back up at full rate for 10 mins. This repeated over the remaining off peak period.

This is a new issue. It used to work correctly, example from back in November:

Here are the WW settings

And here are the logs from last night

Grateful if you could take a look at this. 🙇

    Avenir Right, so this looks like an issue with the Giv backend as indicated by the response, where the inverter had timed out on all the settings, including the retries.

        admin Ah yes. So I guess the workaround is cross fingers and hope it doesn't happen again!

            Avenir Yeah - bit annoying really. Would be interesting to see whether this was the same issue with others too.

            We will increase the back-off factor for the retries. I guess that's all we can do at our end.

              24 days later

              Hi @admin I am still seeing the battery bouncing between charge and discharge in the 'off-peak' period, even though WW is set not use the battery off-peak. It's not quite as extreme as the example in my post above, but still present. As previously noted, this wasn't an issue back in November. I can't see any obvious timeouts or errors in the logs.



                Avenir Doesn't look like there's anything we'r edoing wrong on that occasion. It may simply be a side-effect of the charge rate adjustment and the way this works on Giv systems tbh.

                Back in November, we didn't have charge rate adjustment in place I don't think.

                Would be worth toggling 'Adjust charge rate' to Off and you probably won't see these wobbles.

                    inferior-opposite

                    I've found the same. The activity log says a hold is in place but the battery is still active. As it happens, the sun has unexpectedly come out so I'm happy that the hold didn't work as my battery is charging

                    Thinking out loud… the battery should be paused for the duration of the off-peak period when the charge is complete, but the charge is never completed because the target value is never met (in my case it's always 1% short). Could that be what's going on?

                    So there's several different things going on.

                    Hold charge is not being used on the regular charging schedules. I would expect the exact same behaviour you are seeing if you applied the charging parameters via the Giv app or portal, including adjusting charge rate.

                    For the Agile charge slots, where we apply the hold, we effectively set discharge power to 0.

                    For some Giv Hybrid inverters this does actually not work as you'd expect, as it can allow a few hundred watts through. More on that in this thread: https://community.wonderwatt.com/d/110-release-363-octopus-agile-window-hold-charge-functionality/51

                    I get the same result when charging at max rate. But it worked fine back in November.

                    I don't think the inverter is the problem, because we can see there was no SOC wobble issue up until mid December 2023. The last update to the BMS was on 2023-11-30, but I can see the battery was holding charge in off-peak just fine on 2023-12-08.

                    In Mid December the WW variable charge rate feature was introduced. The battery was no longer able to meet the target, typically 3–6% short. I worked around this by overstating the battery capacity by up to 15%. I can see the SOC wobble is evident on December 26, when it completed a charge early.

                    I will try and set a timed charge via the GE portal and see what happens.

                    @admin As you correctly predicted, I got the same SOC wobble when setting via the Giv portal 'Timed Charge' settings. The wobble is actually pretty large, draining the battery at the inverter's full rate of 2.6kw – so I think we can discount the possibility that it's the inverter 'leaking' a few hundred watts.

                    Looking back in the logs, back in November/December WW would send a command to 'Enable Eco Mode', which is no longer sent. Could it be that this command prevented the issue I am seeing?

                      Avenir

                      We don't touch Eco-mode for charge schedules, so your default should be to have Eco-mode on, have you not got Eco-mode enabled currently?

                      We only set Eco mode back to true after a Timed Discharge.

                          admin Hi, thanks for the response. Eco mode is currently on.

                          The charging logs up to mid December look like this, with the Enable Eco mode command, which I assume is being sent by WW.

                              Avenir Thanks for digging that out.

                              So back then we were using the presets, but they were causing too many Inverter Timeouts.

                              I don't think it's related to Eco-mode. It's more likely the Enable DC Discharge being set to False.

                              We may need to do this during charge windows, and possibly during on hold.

                                  7 days later

                                  admin in the meantime, a workaround would be to allow the charge rate buffer value to be user configured. For example a +4% value might allow me to better cover the full period, and avoid the SoC bounces.

                                      Avenir Yeah, though I think at lower charge rates for Giv, the end SOC target ends up being generally less accurate anyway. So I'm doubtful a simple percentage based offset would work, of course unless you specify a high enough buffer.

                                      We can have a look.