Hi all. Can some educate me please. I have set the timed discharge to 40% (between 4-7pm (Im with Octopus)). Having just opened the App i can see the power drain to top up the PV generation is coming from the main and not the battery. Is there a reason why?. Thank you.
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You’re still in your timed window. When it reaches 40% it doesn’t stop and return to eco. It goes into a hold mode. No power in. No power out. When 7pm rolls around it will return to eco.
Until then it will draw from solar and top up with grid.
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Thanks very much indeed 
Sorry, it just occurred to me. When i had the system installed and got set up with Octopus, their prime export window being 4-7pm. So i set my export to mirror that. I’m normally at 100% at 4pm. So if i reduced the window of export but retain the lower limit to 40%, would this put strain on my battery. i.e. a faster export rather than a trickle export. I hope this makes sense..?..
Your battery will always export at full power no matter what times or % you enter. Unless you’ve set the max discharge rate or set a G100 limit (installer only setting that one).
I don’t recommend you changing the max discharge as that also limits how much power it can supply the house.
While actively exporting it also powers the house. It’s only when it gets to the set percentage it goes into hold mode.
What I do is tell it to discharge for xx minutes. Very easy to do with home assistant. I know that at my max export of 3.6 how long it will take to reach a certain percentage and I do the math. I will be setting up Predbat in the future to do all this for me.
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Hi Steve, Do you get a higher rate between 4&7pm? If not, then there’s little advantage to discharging at that time.
But, if you set the battery to export, rather than discharge, it should power the house as well.
I’m doing something similar (exporting between 1730 & 1900 to 35%), that leaves me enough to run the house until midnight and cook if needed but if I start cooking during the export period, it still prioritises the house.
If you look at your data, you’ll probably find your battery has emptied to 40% within about 90 mins, or at least well before 7pm.
Hi Dave. My Export window at the best rate is 4-7pm (Octopus). Upon checking i had the export time set at 4-6pm (discharge is not activated). So today, I’ve changed that to 4-5.30pm to go down to 40%. I’ve had a look through the data and going from 100% to 40% takes 1hr 25mins. I want to use the remaining 40% for us to have an evening meal and the usual family routine without drawing from the grid, drawing from the battery only.
That’s pretty much how I do it now, I tried exporting 4-7 pm but it just drained the battery unless I reduced the discharge rate, but that wasn’t enough to power the oven! So I settled on the 1.5 hrs to 35% at max discharge rate.
Glad you’ve got it sorted.
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