FoxESS Community - Owners & Installers Forum

Hi, I want to add an extra battery to my system. I have a fox-ess H1 hybrid inverter with 6 batteries, what I want to do is add an extra battery.

Do I add it below the stack as the last battery or add it on first.

Would appreciate any help
Regards

David.

Which batteries are they ?

Typically you add it to the top of the stack - if HV batteries below the BMS and the chain the next battery on, if ECS or EQ batteries then the top battery is the master so it goes underneath that one.

Thank you for your reply. As it goes I first had three batteries when installed by a company, so then I added another 3 batteries but just added them in sequence and everything is going fine. As my inverter can only accept 7 batteries in total so I brought another one to take it to 7 and this is where it becomes unsure for me.

I have already tried it in sequence i.e. last one but it set off the alarm and on my BMS it goes from 4 to 2 on the soc,s

So I hope it is right that I add it after the BMS which will end up being the first battery after the BMS.

Is this right.

Thanks for your help.

David.

Yes it should be added after the bms and before the next battery - if there are Addr dip switches on the battery they should be left off - and you will need to rotate the dial on the BMS for 7 batteries (i.e. set to 5)

For HV batteries the RS485 cable from the BMS should be plugged into RS485-1 and the RS485-2 daisychains onto the next battery RS485-1 and it repeats down the stack.

You should add new batteries at approx 50% SoC

Thank you for all your help couldn't have done it without you.

There is one thing I'm not sure off, this is because I was left with no instructions when having the system fitted, what should be the Battery Reserve Capacity and what should the System Min SOC be. I know people will say different figures but what is an average.

Once again thank you for all your help.

David

Great, glad you’ve got it all working.

If you don’t have an EPS fitted (i.e. an emergency power change over switch which needs to be wired into the inverter), they should both be set to 10%, the only time I would set it higher (~20%) is if you know there was an extremely cold spell coming up where your batteries may stop charging.

If you do have an EPS minSoC should be set to 10% and your Battery Reserve set to the level you want to guarantee is in the batteries should the grid fail.

Once again thank you to all who helped me through my situation, everything is working fine thanks to you.
There is one more thing I would like to know and that is ( my system consists of 12 solar panels plus a hybrid 3.7kw H1 inverter and 7 fox-ess HV25 batteries) can I add another system along side my existing set up.
The reason I ask this is because Octopus Energy do not have a tariff for fox-ess.
Thanks again

David.