Low oil content circuit breaker for high currents - has large dia. hollow switching pin, and insulating evacuation tube extending into hollow pin

摘要

Underneath the circuit breaker is provided an arch extinguishing chamber. A hollow, thin-wall switching pin controls transverse flow channels for high current extinguishing. Hydraulically in series are quenching pockets for extinguishing low currents. Into a lower crankcase moves a switching pin acting as piston pumping extinguishing liquid into upper pressure equalising chamber. An insulating tube with an upper funnel penetrates into the hollow pin up to the level of the uppermost quenching pocket, in order to evacuate the switching gases. The tube has relief apertures at the level of the transverse channels and in connection to the same. The lower end of the hollow pin forms a large piston surface for liquid displacement.