Hello,
Two Modbus RTU masters can communicate in the same network ??

 

By the Modbus standard, no, because packet collisions result in poor or no communications.

With a separate bus arbitrator module between the Masters and the slave bus, Yes.

See these earlier discussions on the same topic:
https://control.com/forums/threads/serial-port-expander-for-modbus-master-device.48045/
https://control.com/forums/threads/modbus-many-to-many-connection.15318/

Three bus arbitrator devices that have been mentioned:

MULTII-PORT™ Model 366-10P-XYZ https://www.miille.com/366-10p-xyz.htm

ICP tSH-73x serial port sharer arbitrator https://www.icpdas.com/en/product/tSH-725

ADF HC67146 bus arbitrator bus arbitrator https://www.adfweb.com/Home/products/modbus_modbus.asp?frompg=nav3_1