What cable is used for RS-485? What cable is used for Ethernet? A bit confused
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As the title says. These past two days, I finally figured out a bit about communications. But there are still some uncertainties. For the 485 (i.e., serial port) mode and the Ethernet mode, what types of cables are used for connection respectively? Is twisted pair used for all of them?
First, figure out what the stranded wire is used for, and then consider your question – you’ll understand.
485 is a standard serial signal; using twisted pair is sufficient, as the requirements for serial data communication speeds are not high.
Do not use Ethernet cables; 485 cables generally require a characteristic impedance of 120 ohms. However, the distance is not far, so a 1.0 twisted-shielded cable will also work. For insurance purposes, Siemens’ purple Profibus cables can be used, though they are a bit more expensive