FoxESS Community - Owners & Installers Forum

Good morning all,

I don't yet have a battery, but I am going to get one very soon and I'd like some advice on how to set it up please.

I'm going to purchase the EP6 5.76kWh battery.
I have roughly a 7kw solar system. (3.96kw existing system + 3kw Fox system)
I have the Fox ESS H1 5kw G2 inverter.

Key considerations:
I cannot be paid anything for any FIT, due to an existing rent-a-roof lease, so don't care what goes back to the grid.
I don't have a cheaper night time rate lecci tariff at the moment, so doesn't matter when I use the grid to charge the battery.

My thought process is that the solar system would be in self use during the day as it currently is, and any excess unused solar would charge the battery. Then at around 4pm the battery would be allowed to be used as the solar starts tailing off and we start using lecci for cooking etc.

How long does the EP6 take to charge if it is at its lowest and you charge it only from the grid?
Would it be sensible for example to set it up so that if it is not fully charged by 3pm each day, between 3pm and 4pm the grid is enabled to ensure the battery is fully charged ready for use after 4pm.

I don't think we need the battery in the mornings at all, just in the evenings. Therefore I don't think there is much benefit in charging the battery over night and then not using the solar that is generated during the day to charge it.

Appreciate any advice and thoughts, and also how you go about setting up this kind of schedule.

Cheers!

If the Fox hybrid inverter can see all of the solar from the other inverter the EP6 will be able to charge near the H1’s limit of 5kw, otherwise it’ll be restricted to the 3kW on the Fox system - hard to be precise as it depends on so many variables, suns elevation, cloud cover, home usage etc.. but on a good day (April-October) charging from solar 10% soc to 100% would be done in a couple of hours, in the worst winter months it probably wouldn’t charge at all.

If charging from grid and assuming temperature is ~20C it can charge at near the inverters maximum 5kW, but you can’t charge only from grid when solar is generating as it will use the excess before it uses grid - the only time you’ll be able to charge only from grid is when there is no PV generation.

However if there is no advantage in price through the day for grid consumption I wouldn’t charge the battery from grid to use it later, you’ll get around 10-15% of losses through conversion, storage and recovery and so it would be cheaper to use solar to charge the battery as much as possible and then use that until it runs out, deferring to grid when that happens - so basically leave it in Self Use all day to do that.

Thanks Dave that is great info.

Yes the Fox will be able to see the solar from the other inverter.

So can you tell the system to ensure the battery is always topped up by 4pm? Can you also tell the system not to use the battery between something like 9am and 4pm?

Can you tell me how you setup some of these schedules please?

Have a look and bookmark Will's videos.
https://www.youtube.com/@iameccles/videos


The direct video to help you is here