Model 61201 Plastic fiber optic RS422/RS485 - Application:
PC controls RS485 bus system over fiber-optic cables

Background knowledge:
Control circuits are often electrically isolated. If the controllers are
grounded over the control bus and the PC, the entire control circuit might be
disrupted by equalizing currents. It must be ensured that the bus is
electrically isolated when connected to the PC, or that the PC is isolated by
suitable measures such as UPS.

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