Industrial Modbus RTU 8-ch Relay Module with RS485 Interface, Multi Isolation Protection Circuits, 5V Power
Is a special protocol converter required to connect Modbus RTU serial interface devices to an Ethernet network? Is the serial device server sufficient?
Acrel Artu-K32 Cheap I/O Module Modbus RTU with 32 Switch Input for Electric Meter Data Collect - China Multi-Circuit Remote Terminal Unit, Modbus RTU | Made-in-China.com
4-ch Modbus-RTU Relay Switch Module Signal input output RS485 TTL Controller US | eBay