I understand your problem! You are just changing the slave id/unit but you have to change the port number on the same IP. ie: 10.10.20.30:502 is your main PAC-4200 access and 10.10.20.30:17002 to access Slave-1 if the RS485 bus is connected to the "MOD1" slot.

here is the official document link: https://support.industry.siemens.com/cs/attachments/34261595/manual_pac4200_en-US_en-US.pdf?download=true

see the page number: 41

Although it's too late to answer but it may help someone!

Thanks,

Aman

New question published by Vinizuca is split to a separate thread with the subject Modbus Rtu over Tcp via Pac4200: can read the PAC4200, but slaves return the same value as the PAC4200. .

Best regards
Jen_Moderator