RS-485

The RS485 interface has been developed for serial high-speed data transmission over long distances and is widespread in the industrial sector. While the RS422 only allows the unidirectional connection of up to 10 receivers to one transmitter, the RS485 is designed as a bidirectional bus system with up to 32 participants. Physically, the two interfaces differ only slightly. An RS485 bus can be set up as a 2-wire as well as a 4-wire system. The lines of this industrial bus interface are operated in push-pull mode; only two lines are required, which are controlled half-duplex.

The benefits of RS-485 technology
  • Each station can exchange data with any other station due to multimaster capability
  • Set up as a 2-wire as well as a 4-wire system
  • Connection of several transmitters and receivers (up to 32 participants) with the help of a protocol
  • Distance between two terminals can be increased significantly: RS-485 meanwhile supports cable lengths of up to 1.2 km
  • Data transmission rates of up to 1 MBit/s

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