[Help]: In my parallel set up, the wrong (i.e. slave) inverter is updated

[Chris-93SAR]

❓ Configuration Help Request

Home assistant core-2026.8.3
Plugin Version 4.2.3
Inverter 2x S6-EH1P6K-L-PLUS in parallel (battery is shared)

🔍 Issue Description

I set up the Integration’s Device Info to reference the master inverter(see screenshot).
Solis Cloud confirms this as the serial number of the Master Inverter (see screenshot).
Unfortunately, when I try to update items such as the charging and discharging slots or Export Calibration Value it is the Slave inverter that is updated. Such updates have no effect as the master inverter controls both.

📸 Screenshots / Logs

Add logs or screenshots to help explain.

➕ Additional Context

I am new to Home Assistant so asked for help in the general discussion but have received no replies.

[Chris-93SAR]

Perhaps of some use...
When using the PC interface for Solis Cloud I can update the slave inverter (not allowed in the Phone App).
Confirmation for the slave includes "rs485ComAddr: 258" and only the slave is updated
The same action for the master has "rs485ComAddr: 257" and both the slave and master are updated

[Pho3niX90]

How did you exactly set this up? From the symtoms it seems as though you have actually setup the slave in homeassistant. If it were master, it would update both inverters.

You need to make sure you are using the correct IP, and slaveId

[Chris-93SAR]

Thank you for responding, the symptoms do, indeed, suggest a set up error, but I cannot see where I make the bad entry. I used HACS to install this so was hand-held throughout.
There is one datalogger for the two inverters and it is plugged into the Master, this is the SolisCloud screen for it.

and for the slave inverter

The Home Assistant “Reconfigure Inverter” screen includes:
Conection_type TCP (WiFi Dongle) [the datalogger actually has a direct LAN connection]
Modbus Slave id 2 [I assume this is the Address field above]
Default Poll intervals
Full Poll profile
Inverter Model S6-EH1P
Updated to V2 Firmware
Parallel inverter operation
Has battery storage
IP Address 192.168.1.83 [matches the datalogger screen]
Port 502
Connection S2_WL_ST

Is there anywhere else it might help to look?
Chris

[Pho3niX90]

Slave id should be 1, to read master. It's no asking which number the slave inverter is at, it's modbus terminology that can be confusing.

So, just change your connection to slave id 1

[Chris-93SAR]

Thank you, I wondered if there was terminology I wasn't aware of so I had tried to do that using the three dots dropdown item "Reconfigure" in settings > integration but submitting the new value (1) received the message:
“Nothing is accepting Modbus connections on that address and port. The device may be reachable (it answers ping) but not serving Modbus — check that Modbus TCP is enabled on the datalogger. Recent Solis logger firmware is known to close local port 502; an RS485-to-TCP bridge is a workaround.”
Solis Cloud continued to work throughout my attempted change.
Is there a proper way to update this value do this or should I delete and apply the integration afresh?
Chris

[Pho3niX90]

Thank you, I wondered if there was terminology I wasn't aware of so I had tried to do that using the three dots dropdown item "Reconfigure" in settings > integration but submitting the new value (1) received the message: “Nothing is accepting Modbus connections on that address and port. The device may be reachable (it answers ping) but not serving Modbus — check that Modbus TCP is enabled on the datalogger. Recent Solis logger firmware is known to close local port 502; an RS485-to-TCP bridge is a workaround.” Solis Cloud continued to work throughout my attempted change. Is there a proper way to update this value do this or should I delete and apply the integration afresh? Chris

After the change, perhaps try restarting home assistant and the wifi dongle. If that still has issues, try creating the inverter.

[Chris-93SAR]

Reconfigure returned the "Nothing is accepting..." message even with unchanged settings.
I have already specified the serial number of the master inverter for what is the connection to the slave and cannot change it in reconfigure so, being a very inexperienced user, it took a few days to pluck up the courage to deleted the device and re-add it
Courage clearly not actually required since the new device had all the same entity names so the associated dashboard items continued to work seamlessly.
The only difference is that the writes now go to the Solis master inverter.
Thank you for your help and patience.