First introduced in 1962, RS-232 is a single-ended data transmission standard; yet despite rumours of its early demise, it continues to be widely used throughout the industry for communications over a short cable.
To achieve a robust data communications link in harsh industrial environments, the RS-232 diagnostic port must provide an isolated interface between the RS-232 cable network and the connected systems to protect against voltage spikes and ground loops within the noisy environment and improve system reliability.##IMAGE_2_C##Power isolation of the RS-232 communication link is obtained by using an isolated DC-to-DC power supply.
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An isolation barrier galvanically isolates the RS-232 bus from each system connected to it, allowing digital data to travel between two points but preventing the flow of ground loop currents; this reduces signal distortion and errors by removing noise that gets coupled onto the communications cable.
You can read the rest of this article in the September issue of Electronic Specifier Design by clicking here.