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mikeseaman3000 avatar image

Modbus TCP & Control of Cerbo GX/Quattro

Hi Everyone,


I need a little help with Modbus Control. I have a Cerbo gx and quattro unit with pylontech batteries. It is all working perfectly however i am looking to interface to my home automation system.


Does anyone have experience with Modbus TCP registers on here?

I am looking to enable and disable charge plus also have the option to maximise the output of the inverter so that I am able to to discharge to grid where possible. Any help with some configurations of the Modbus.

So basically any help with modbus config is great. I have got the communication working perfectly and able to read values from the cerbo gx, i.e. SOC of batteries. via modbus.


Appreciate any help.


Thanks

Mike

MultiPlus Quattro Inverter ChargerModbus TCPcerbogx
4 comments
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Have you downloaded the list of registers? It details which are writeable and which not.

First place to start is to see if what you want to set can be set.

I want to change the ESS inverter limit by time of day and weather, unfortunately this register does not exist as far as I can see so that pretty much torpedos my automation plans.


Hey,


Thanks for the reply. Yeah i managed to download the registers, but i cannot seem to force the charge and discharge over Modbus. Any ideas?


Is there not a way to write to the grid setpioint for Inverter Limit. You can do a calc in your external controller that takes the consumption and limits what the inverter outputs?

nickdb avatar image nickdb mikeseaman3000 ·

what home automation are you using?

I have been working with home assistant which seems to work fine.

Hi nickdb,

Can you tell me which registers you are using to control the charge / discharge limits? I am running ESS in mode 1 (maintaining 0 watts grid flow)
I have reviewed all the writable registers in the CCGX Modbus TCP register list v2.7 but cannot find any that will allow to control these two via HA.
1633948536822.png

What I am wanting is not to force the rate, only to limit the rate.

1633948536822.png (48.1 KiB)
0 Answers