Earthing switches with fault making capacity
Indoor Installation
12…36kV

General

Earthing switches with fault making capacity can be reliably closed against short circuit currents, thus protecting the operator and switchgear in the cause of inadvertent operation. Naturally, operation behind a closed compartment door forms part of the overall cubicle safety. There are two forms of earthing switch: independent earthing switches and combined earthing switches with integral current transformers. The current transformers of the combined version form the mounting base for the earthing switch contacts thus reducing the space required in the cubicle. Every earthing switch is fitted with a spring operating device which makes the closing capacity independent of the operating speed. The control side of the earthing switch and direction of current flow can usually be chosen without limitations except for a few models with integral current transformers.

Standards

IEC Publication 129 (1984)
IEC Publication 694 (1980)

Materials

The frame is zinc plated steel plate. The current carrying parts are silver plated copper and the insulators are made of cast epoxy resin.