Industrial automation buyers are searching again for two old but sticky terms: Modbus​ and RS485. They are not the same. RS485 is the physical layer—the twisted-pair “road” that moves differential signals up to 1200 meters and lets many devices share one bus. Modbus is the communication protocol—the

Modbus protocol is a universal language applied to electronic controllers. Through this protocol, controllers can communicate with each other, through networks such as Ethernet, and other devices, which has become an industry standard. With it, control equipment produced by different manufacturers c