Interrupting subassembly for switching appliance

A multi-pole electromechanical switching device having opposing front and rear ends, comprising several principal double switching poles each provided with fixed contacts housed in an arcing chamber and mobile contacts located on a contact carrier that is mobile in translation inside the arcing chamber responsive to attraction of an electromagnet located at the rear end of the device, the switching device further comprising principal housings for the principal mobile contacts of the principal poles, said principal housings aligned transversally to a direction of displacement of the contact carrier and separated by principal inter-pole separations of the arcing chamber, wherein:

• the contact carrier comprises auxiliary housings for auxiliary contacts, said auxiliary housings aligned transversally to the direction of displacement of the contact carrier and located in front of the principal housings,
• the contact carrier comprises, between the principal housings and auxiliary housings, a vertical insulating wall comprising several polar insulating side walls separated by inter-pole slits,
• the arcing chamber comprises two half-chambers assembled by interlocking and/or mutual clipping along a horizontal plane, such that at least one of said two half-chambers comprises guide elements and stop elements for cooperating with the contact carrier, and
• each said half-chamber comprises an insulating partition located between principal contacts and auxiliary contacts.