Informational Brochure

Accessories

Grounding Switches

FAS-GRD, AG7 and AG8 grounding switches can be applied on either the hinge or jaw end of most switches for grounding lines on equipment during inspection, maintenance, or repair. The 3- pole grounding switch is frequently interlocked with the main switch on which it is mounted, to prevent both switches from being closed at the same time. Grounding switches can also be supplied with their own separate base and insulator stack rather than attached to a disconnect switch. Grounding switches must be designed, built and tested to withstand the rigors of associated equipment, high momentary ratings, ice-breaking ability, and wind-loading resistance.

High-Speed Grounding Switches (Automatic)

Automatic high-speed grounding switches provide the most economical means of transformer protection. Their application has become well accepted at the result of the excellent reliability of modern transformers, extremely fast relay and circuit breaker operation, and last but not least, dependable design. The purpose of the high-speed grounding switch (HSG) is to create deliberate fault upon a signal from the protective relays of the faulted transformer. Fault current relays trip the remote circuit breaker. With high speed components used in the scheme, a transformer is de-energized with a few cycles after it develops an internal fault, thus limiting costly transformer damage. Since the HSG is a fault-initiating device, it is normally supplied for single pole operation; however, 3-pole operation can also be supplied. It can be reset with either a hook stick or an operating handle at ground level.

The HSG switch can be supplied in these forms: x On any non-rotating insulator of any switch. x As a complete unit with its own base and insulator.

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