Auto-blow switch

Opening process on an SF ₆ circuit breaker

SF ₆ self-blowing switch, two switches per phase in series in a horizontal design

Self-blowing switches are circuit breakers that are used in high-voltage switchgear . They are high in a position short-circuit currents to be interrupted by the resulting switching arc blown during the switching operation with gas under high pressure and remove as soon as possible. In the high-voltage range, sulfur hexafluoride (SF ₆ ) is used almost exclusively as an extinguishing agent. Unlike ordinary SF ₆ - Kolbenblasschaltern the Self-blast requires much less drive energy for the extinguishing system.

The development of SF ₆ self-blowing switches goes back to work by Winthrop Leeds and colleagues at Westinghouse Electric in 1957.

functionality

During the switch-off process, the extinguishing gas is first compressed by the piston movement and then flows under high pressure out of the chamber over the burning arc. With the self-blowing switch, a sensible housing construction is used to achieve additional overpressure due to the high temperature of the arc. This saves drive energy for the compression of the gas.

literature

• René Flosdorff , Günther Hilgarth: Electrical energy distribution . 8th edition. Teubner, 2003, ISBN 3-519-26424-2 .

Individual evidence

1. ^ Westinghouse Pioneers Development of Sulfur Hexafluoride (SF6) Circuit Breakers. Retrieved April 18, 2013 .