E – 1636 Gas-Insulated Substations; An Overview

This course provides an overview of (GIS) or Gas Insulated Substations. A gas insulated substation (GIS) is a high voltage substation in which the major conducting structures are contained within a sealed environment with a dielectric gas known as SF6, or sulfur hexafluoride gas as the insulating medium.

In comparison, a conventional (AIS) or Air-Insulated Substation, uses atmospheric air as the dielectric gas medium, as these types of substations are almost always located at outdoor locations.