Glossary of Termination Terms

Class 1 Termination:

Provides electric stress control for the cable insulation shield terminus: provides complete external leakage insulation between the cable conductor(s) and ground; and provides a seal to the end of the cable against the entrance of the external environment and maintains the operating design pressure, if any, of the cable system.  This class is divided into three types:

• Class 1A: For use on extruded dielectric cable
• Class 1B: For use on laminated dielectric cable
• Class 1C: Expressly for pressure-type cable systems.

Class 2 Termination:

Provides electric stress control for the cable insulation shield terminus, and provides complete external leakage insulation between the cable conductor(s)

Class 3 Termination:

Provides electric stress control for the cable insulation shield terminus.

Indoor Termination - Dry:

A termination intended for use where it is protected from solar radiation and precipitation and not subject to periodic condensation, or other excessive humidity (90% RH or more). May be installed in air conditioned or heated areas.

Indoor Termination - Wet:

A termination intended for use where it is protected from direct exposure to both solar radiation and precipitation, but is subjected to climatic conditions that can cause condensation onto the termination surfaces.

Outdoor Termination:

A termination intended for use where it is not protected from direct exposure to either solar radiation or precipitation.  These are Class 1A, 1B, or 1C terminations.  Class 2 terminations may also qualify.

NOTE:

Some cables below 15 kV do not have an insulation shield. Terminations for such cables would not be required to provide electric stress control. In such cases, this provision would not be part of the definition.

---from: 3M Electrical Products Catalog p. 204