Galvanic isolation

"Electrical isolation" redirects here. Not to be confused with electrical insulation.
A transformer is the most widespread example of galvanic isolation.
An opto-isolator is a very popular method of isolation in digital circuits.
Cross-section of dual in-line package opto-isolators. Relative sizes of LED (red) and sensor (green) are exaggerated.
Everlight EL817 phototransistor opto-isolator in DIP-4 package
Halo TG110-S050N2RL 10/100BASE-TX Ethernet pulse transformer in SO-16 package. Decapped sample on the right.

Galvanic isolation is a principle of isolating functional sections of electrical systems to prevent current flow; no direct conduction path is permitted.[1][2]

Energy or information can still be exchanged between the sections by other means, such as capacitive, inductive, radiative, optical, acoustic, or mechanical coupling.

Galvanic isolation is used where two or more electric circuits must communicate, but their grounds may be at different potentials. It is an effective method of breaking ground loops by preventing unwanted current from flowing between two units sharing a ground conductor. Galvanic isolation is also used for safety, preventing accidental electric shocks.

  1. ^ John Huntington Show Networks and Control Systems: Formerly Control Systems for Live Entertainment 2012 ISBN 0615655904, page 98
  2. ^ Cite error: The named reference Schneider was invoked but never defined (see the help page).