Discharge power set to zero but still discharging

9 comments started 2024-03-12 last 2024-03-18
GivEnergy ProductsHybridBattery
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#1 Niceguy

I've a 5kW inverter and a 9.5kWh battery with a maximum power of 3.6kW. I'm charging up my battery on the cheapest 6 Agile slots available overnight, which works fine. But I'm setting the maximum discharge power to zero overnight (so that the battery doesn't discharge itself in between the cheapest slots, when it's still quite cheap). Despite this the battery is still partially discharging itself at about 300W, with the rest of home demand being met by the grid.

I expected the battery to not discharge with the maximum power set to zero. Has anyone else experienced this?

#2 nophead

Yes it is bug in the latest version of the firmware. It no longer accepts 0, the minimum is 1 which should be 1% but is 300W, which is about 10 times more.

The only way to stop it discharging is with a timed pause.

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#3 Rubikcube

Turn off ECO to stop the battery meeting demand.

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#4 Niceguy

Thanks for the suggestions, but actually I'm been trying out WonderWatt and that's been producing the settings.

I wonder if ECO can be turned off via the API, in which case I'll suggest it to WonderWatt.

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#5 DD

Niceguy Yes it can - it's setting #24 on my system:

24 Enable Eco Mode : Value must be either true or false

But the advantage of using timed pause, if available on your system (probably not gen-1) is that you can just configure it once and forget about it. Problem with turning eco off is that you need to turn it back on every morning, and off every night. A network outage could leave it in the wrong state.

96 Pause Battery                            : Value must be one of: 0, 1, 2, 3 (Not Paused, Pause Charge, Pause Discharge, Pause Charge & Discharge)
155 Pause Battery Start Time                 : Value format should be HH:mm. Use correct time range for hour and minutes
156 Pause Battery End Time                   : Value format should be HH:mm. Use correct time range for hour and minutes

You could use direct local control which is less likely to suffer from network outages.

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#6 Niceguy

DD Thanks DD. I've raised a Feature Request with WonderWatt. It's a GivEnergy failure, but I hope that WonderWatt will implement the change so that their utility works more effectively in the real world.

#7 Wonder Watt

DD Niceguy

I don't think this is related to Eco mode. Others have noticed this phenomenon when setting charge power to 0% and a max of 300W or so is used for house load, but remainder is met by the grid.

Regarding the specific Pause settings, those pause settings are not the settings the Giv app's pause use, right? AFAIK the Giv app' Pause simply sets discharge and charge rates to 0.

Also - the last thing we want to do is implement different if..then..else..branches for all sorts of Giv inverter flavours. Because even though some settings in the mid and high 100s registers seem available, they cannot be read or written to on earlier gen hardware.

We'll expect that the additional action of setting the 56: Enable DC Discharge to False would do the job and will be testing this next few days.

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#8 DD

Wonder Watt We'll expect that the additional action of setting the 56: Enable DC Discharge to False would do the job and will be testing this next few days.

I have a feeling that 'enable DC Discharge' is just about configuring either timed-discharge or timed-export. It's somewhat redundant, since you can (probably) do that by setting start and end times to the same value - there are quite a lot of timers in the system, and most of them are disabled that way, rather than with a separate flag.

So if 'enable DC discharge' is on, then the discharge mode is reported as either timed-export or timed-discharge (depending on whether eco flag is on). I've just confirmed that disabling it has no effect on battery discharging to power my home (in eco mode).

My system has 10 discharge slots. I've not checked whether turning off 'enable dc discharge' turns them all off, or just the first one. (I run i timed-discharge mode pretty much all the time, ie usually have 'enable dc discharge' enabled.)

Yes, AFAIK 'pause' on the app is implemented by setting charge and discharge powers to 0, not using the timed-pause control (which I don't think is available on gen-1 hybrid, for example).

Testing now.. turning off eco mode turned battery discharge power to 0 (as reported by rubikcube's inverter app). Setting discharge power to 0 had no obvious effect (since consumption is only about 300W anyway). Using timed-pause to disable discharge dropped it to about 26W.

#9 hoggy

You can just set the "reserve" value to 100% and it should stop it dead in every firmware.
It's an old trick...