摘要 |
An arc extinguishing chamber for an electrical switchgear device, notably a circuit breaker or a current limiting unit, comprises an almost tightly sealed case made of gas-producing insulating material to house separable contacts with electrodynamic repulsion. The movable contact, in the shape of a bridge, appreciably follows the internal configuration of the case playing the role of a piston arranged on both sides of a first compartment generating pressure due to the action of the arc, and a second compartment communicating with the first via a minimal clearance J. The pressure in the second compartment is lower than that in the first compartment. Magnetic circuits can be arranged to accelerate the movable contact to the open position.
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