KH with CS4800 add 8th battery

[UK_KH_User123]

Hello:

I believe the original specs were the one master battery plus six additional units. I heard this limit was raised by one so seven units can be in the stack plus the master.

I enquired with my installer and they said "Yes this is true but for a different module battery. unfortunately you have maxed out the ecs modules where the eqs modules you can have an extra battery."

I then found a pdf with specs from 2025 ( https://www.fox-ess.com/download/upfile ... 250107.pdf ) that seem to back up the claim that my stack is 'full' at 7 boxes. Is that new data sheet wrong? If it is really permitted with my KH10.5 inverter and the CS4800 4.66kWh / 104 Ah battery, how can I prove it to the installer?

Thanks!