A circuit breaker includes: fixed contact points; and a moving contact assembly. The moving contact assembly includes: a shaft; a moving contact that is held in the shaft; and springs that apply torque to the moving contact. The shaft includes: stopping faces that are formed in a direction opposite to the direction in which the moving contact rotates; and guiding faces that are curved from the stopping faces. The moving contact includes: first surfaces that are formed on the radius of rotation of the moving contact; and sliding surfaces that are located at an angle to the first surfaces and slanted toward the center of rotation with respect to the line of action of a tangential force of torque at the points of contact with the guiding faces.

An electrical contactor that includes separable contacts that include a first pair of mating contacts and a second pair of mating contacts. The electrical contactor also includes a first portion that includes the first pair of mating contacts and a solenoid plunger that is configured to receive a plunger rod; The electrical contactor additionally includes a second portion that includes the second pair of mating contacts. The plunger rod is configured to be inserted within the solenoid plunger and rotated towards the second portion to be threaded into the second portion to enable the second portion to be pulled up towards the first portion. The second pair of mating contacts are configured to move closer to the first pair of mating contacts until the second pair of mating contacts mate with the first pair of mating contacts to increase a wear allowance to a predetermined desired level.

An electromagnetic switch includes a main contact housing portion housing a main contact mechanism having a pair of fixed contacts fixedly disposed maintaining a predetermined interval and a movable contact disposed to connect with and separate from the pair of fixed contacts in a contact housing case; an auxiliary contact housing portion housing at least two auxiliary contact mechanisms having fixed contacts and movable contacts disposed connecting to and separating from the fixed contacts; and an electromagnet unit having a movable plunger individually coupled to move the movable contact of the main contact mechanism and the movable contacts of the auxiliary contact mechanisms. The main contact housing portion, the auxiliary contact housing portion, and the electromagnet unit are disposed in series.

An electromagnetic switch includes a main contact housing portion housing a main contact mechanism having a pair of fixed contacts fixedly disposed maintaining a predetermined interval and a movable contact disposed to connect with and separate from the pair of fixed contacts in a contact housing case; an auxiliary contact housing portion housing at least two auxiliary contact mechanisms having fixed contacts and movable contacts disposed connecting to and separating from the fixed contacts; and an electromagnet unit having a movable plunger individually coupled to move the movable contact of the main contact mechanism and the movable contacts of the auxiliary contact mechanisms. The main contact housing portion, the auxiliary contact housing portion, and the electromagnet unit are disposed in series.