Abstract: A modular low voltage multipole circuit breaker, including a plurality of identical single-pole breaking units each including a parallelipipedic insulating box having two opposite parallel large side faces and two opposite parallel small side faces, two terminals located at respective opposite parallel small side faces, a stationary contact electrically connected to one of the terminals, a movable contact cooperable between a first position contacting the stationary contact and a second position separated from the stationary contact and a molded case for housing the single-pole breaking units. The molded case has two opposite parallel side walls having the same thickness, the single-pole breaking units being sequentially arranged and parallel to each other and parallel to the side walls such that adjacent single-pole breaking units are spaced apart a distance equal to twice the thickness of the side walls, the single-pole breaking units being spaced apart at a constant pitch.

Abstract: A low voltage multipole circuit breaker having a double housing, each pole including a single-pole breaking unit having a parallelepipedic plastic box having two extended side faces. Contacts are further provided and are associated with an extinguishing chamber housed within the single-pole breaking unit. Several units are mounted side by side in the parallelepipedic box to form a multipole circuit breaker.

Abstract: A breaking device for a low voltage circuit breaker comprises in each pole a switching bar, a pair of stationary contacts connected to the connection terminals, a double-break rotary contact extending in a housing of the bar, and two arc chutes disposed on each side of the bar. Two contact pressure springs ensure elastic positioning of the rotary contact along the longitudinal direction of the pole. Pivoting of the rotary contact takes place around a fictitious axis mounted floating with respect to the fixed rotation axis of the bar.

Abstract: 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.