Application:
Electrical isolation for copper wiring

Background knowledge:
The use of isolators in data lines eliminates interference that is otherwise common at PC connected to RS232/RS485 lines (ground loop, vertical effect, potential differences, remote lightning). Electrical isolators are not to be confused with surge protectors that are often incorrectly marketed for the same purpose:

Surge protectors have no effect on equalizing currents that exist between the connected devices due to the potential differences, and they cannot prevent damage to interface components by such currents.

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