FoxESS Community - Owners & Installers Forum

MattyS wrote: ↑Fri Apr 10, 2026 6:51 pm Some of the registers throwing errors are ones I assume should be working regardless.

Interestingly, the integration seems to think I have a 10kWh inverter. I have a 5kWh. Maybe that's a clue

Ok so my installers HAVE given me a 10kWh inverter version, how nice of them.

I stood there with the installer and we worked together to double and triple check what wire would go where. I'm going to look at the modbus register PDF to see if I can find out whats going on because the integration is suggesting that work mode changing isn't available on my system which is clearly wrong.

tcp://192.168.1.136:502 247: register 41003 is invalid
tcp://192.168.1.136:502 247: register 41004 is invalid
tcp://192.168.1.136:502 247: register 41005 is invalid
tcp://192.168.1.136:502 247: register 41006 is invalid
tcp://192.168.1.136:502 247: register 49203 is invalid

MattyS wrote: ↑Fri Apr 10, 2026 8:10 pm

MattyS wrote: ↑Fri Apr 10, 2026 6:51 pm Some of the registers throwing errors are ones I assume should be working regardless.

Interestingly, the integration seems to think I have a 10kWh inverter. I have a 5kWh. Maybe that's a clue

Ok so my installers HAVE given me a 10kWh inverter version, how nice of them.

I stood there with the installer and we worked together to double and triple check what wire would go where. I'm going to look at the modbus register PDF to see if I can find out whats going on because the integration is suggesting that work mode changing isn't available on my system which is clearly wrong.

tcp://192.168.1.136:502 247: register 41003 is invalid
tcp://192.168.1.136:502 247: register 41004 is invalid
tcp://192.168.1.136:502 247: register 41005 is invalid
tcp://192.168.1.136:502 247: register 41006 is invalid
tcp://192.168.1.136:502 247: register 49203 is invalid

I checked those registers all of mine are invalid except 49203 which returns “1”.

Any firmware updates available for the unit?
I remember they had to update my firmware from the install.

AdamNewberry wrote: ↑Fri Apr 10, 2026 9:08 pm Any firmware updates available for the unit?
I remember they had to update my firmware from the install.

my installer did do a couple of installs, but it appears there are much more recent versions. I'll be speaking to my installer.

here are the versions from my foxcloud:

Version_Master：
9.42
Version_Slave：
1.00
Version_Manager：
1.01
Version_BCU：
1.001

the latest as per Wills spreadsheet are :

Master 1.15
Slave 1.00
Manager 1.10
BCU (Master) 1.04

not sure why the master versions are vastly different.

BOD wrote: ↑Fri Apr 10, 2026 9:00 pm

MattyS wrote: ↑Fri Apr 10, 2026 8:10 pm

MattyS wrote: ↑Fri Apr 10, 2026 6:51 pm Some of the registers throwing errors are ones I assume should be working regardless.

Interestingly, the integration seems to think I have a 10kWh inverter. I have a 5kWh. Maybe that's a clue

Ok so my installers HAVE given me a 10kWh inverter version, how nice of them.

I stood there with the installer and we worked together to double and triple check what wire would go where. I'm going to look at the modbus register PDF to see if I can find out whats going on because the integration is suggesting that work mode changing isn't available on my system which is clearly wrong.

tcp://192.168.1.136:502 247: register 41003 is invalid
tcp://192.168.1.136:502 247: register 41004 is invalid
tcp://192.168.1.136:502 247: register 41005 is invalid
tcp://192.168.1.136:502 247: register 41006 is invalid
tcp://192.168.1.136:502 247: register 49203 is invalid

I checked those registers all of mine are invalid except 49203 which returns “1”.

49203 is work mode I believe.

by the way everyone, I've taken the liberty of indexing the Evo github on deepwiki here: https://deepwiki.com/AdamNewberry/foxess_modbus_EVO

it has an AI that you can ask questions about the code etc. Despite my issues with AI in general it may be quite useful.

I forgot who told me, maybe it was even fox, but I understood that 9.x firmwares are development, typically ship with a factory unit and must be updated.Fox allow you to update firmware via the fox cloud app yourself now. Go to the device tab the click the device icon. It should show you what upgrades are available.

AdamNewberry wrote: ↑Sat Apr 11, 2026 7:09 am I forgot who told me, maybe it was even fox, but I understood that 9.x firmwares are development, typically ship with a factory unit and must be updated.Fox allow you to update firmware via the fox cloud app yourself now. Go to the device tab the click the device icon. It should show you what upgrades are available.

I've just checked and that option is not there. on the device screen it doesn't say any updates are available

On the iOS app?

May be worth firing an email off to fox. They were pretty quick to update mine via support ticket before the self
Update feature came.

AdamNewberry wrote: ↑Sat Apr 11, 2026 8:01 am May be worth firing an email off to fox. They were pretty quick to update mine via support ticket before the self
Update feature came.

I'm on Android. and that is the exact page I'm looking at . no updates, no bubble, no red dot.

I've messaged my installer.

Sorry can’t be of more help. I hope (and suspect) the firmware update will fix it! I couldn’t get the integration going until I got firmwares updated.

AdamNewberry wrote: ↑Sat Apr 11, 2026 8:06 am Sorry can’t be of more help. I hope (and suspect) the firmware update will fix it! I couldn’t get the integration going until I got firmwares updated.

No need to apologise, your advice and integration is of great help to me Thanks!

Modbus all up and running now. Firmware update did the trick. Still need more though. Will speak to Fox

Glad it’s sorted and working.

Hi there Adam/all,

I'm trying to understand modbus a bit more and how to adjust/ add sensors into my home assistant without borking your great work.

I've seen that register 37611 "ambient temperature" isn't being populated by my system, it's showing as 0°C.

Also I'm trying to find a way of reading and writing to the battery warm up function which is at register 53400 to 53415 ( for a 2 BMS system)

Would you know if this is possible?

Edit: just found the actions feature in HA, and I can see that ambient temperature should be possible to get, but it's gain 10 which I assume means value x10.

The warming feature appears to be accurately showing as on, with start and end temperature reporting as per how my installer has set.

Interesting.