A solenoid device includes two electromagnetic coils, two stationary cores, two plungers and a yoke that surrounds the two electromagnetic coils. When a first electromagnetic coil is energized, magnetic flux flows through a first magnetic circuit that includes the first stationary core. When the two electromagnetic coils are energized, magnetic flux of the first electromagnetic coil flows through the first magnetic circuit, and magnetic flux of the second electromagnetic coil flows through a second magnetic circuit that includes a second stationary core. When energization of the first electromagnetic coil is stopped while maintaining energization of the second electromagnetic coil, the magnetic flux of the second electromagnetic coil continues to flow through the second magnetic circuit and a third magnetic circuit that includes the two stationary cores. A magnetism limiting portion is disposed in a portion of the second magnetic circuit that does not overlap the third magnetic circuit.

A relay apparatus incorporates at least first and second relays having respective first and second electromagnetic coils, with a single yoke partially surrounding each of the coils. When current is passed through only the first electromagnetic coil, to activate the first relay, resultant magnetic flux acting on the armature of the second relay is attenuated by passing a current through the second electromagnetic coil to produce opposing-direction magnetic flux. When current is passed in the opposite direction through the second coil, to activate the second relay, the magnetic fluxes produced by the first and second electromagnetic coils become mutually reinforced, thereby reducing the power consumption required to activate both of the relays and to maintain that activated state.

A relay system is provided which is designed to avoid flow of inrush current through a capacitor in a pre-charge mode wherein the capacitor is pre-charged. The relay system includes a pair of power lines, a capacitor, a series-connected assembly, a control circuit, and a relay module. The relay module includes two main switches, a main coil, and a sub-coil. In the pre-charge mode, the control circuit energizes both the main and sub-coils to turn on only one of the main switches. Before entering the pre-charge mode, the control circuit diagnoses the sub-coil. When the sub-coil is determined as being malfunctioning, the control circuit inhibits the pre-charge mode from being entered.

An electromechanical circuit breaker comprising a main contact pair comprising a first main contact disposed on a first main contact bridge; an auxiliary contact pair comprising a first auxiliary contact disposed on a first auxiliary contact bridge, the first auxiliary contact bridge being connected in parallel to the first main contact bridge and wherein the auxiliary contact pair comprises a material that has a higher melting point than a material of the main contact pair; a first armature configured to move the first main contact bridge; a second armature configured to move the first auxiliary contact bridge, wherein the first and second armatures are configured such that the auxiliary contact pair opens after the main contact pair opens, and the auxiliary contact pair closes before the main contact pair closes.

An electromechanical circuit breaker comprising a main contact pair comprising a first main contact disposed on a first main contact bridge; an auxiliary contact pair comprising a first auxiliary contact disposed on a first auxiliary contact bridge, the first auxiliary contact bridge being connected in parallel to the first main contact bridge and wherein the auxiliary contact pair comprises a material that has a higher melting point than a material of the main contact pair; a first armature configured to move the first main contact bridge; a second armature configured to move the first auxiliary contact bridge, wherein the first and second armatures are configured such that the auxiliary contact pair opens after the main contact pair opens, and the auxiliary contact pair closes before the main contact pair closes.

A solenoid device includes two electromagnetic coils, two stationary cores, two plungers and a yoke that surrounds the two electromagnetic coils. When a first electromagnetic coil is energized, magnetic flux flows through a first magnetic circuit that includes the first stationary core. When the two electromagnetic coils are energized, magnetic flux of the first electromagnetic coil flows through the first magnetic circuit, and magnetic flux of the second electromagnetic coil flows through a second magnetic circuit that includes a second stationary core. When energization of the first electromagnetic coil is stopped while maintaining energization of the second electromagnetic coil, the magnetic flux of the second electromagnetic coil continues to flow through the second magnetic circuit and a third magnetic circuit that includes the two stationary cores. A magnetism limiting portion is disposed in a portion of the second magnetic circuit that does not overlap the third magnetic circuit.

A solenoid device includes two electromagnetic coils, two stationary cores, two plungers and a yoke that surrounds the two electromagnetic coils. When a first electromagnetic coil is energized, magnetic flux flows through a first magnetic circuit that includes the first stationary core. When the two electromagnetic coils are energized, magnetic flux of the first electromagnetic coil flows through the first magnetic circuit, and magnetic flux of the second electromagnetic coil flows through a second magnetic circuit that includes a second stationary core. When energization of the first electromagnetic coil is stopped while maintaining energization of the second electromagnetic coil, the magnetic flux of the second electromagnetic coil continues to flow through the second magnetic circuit and a third magnetic circuit that includes the two stationary cores. A magnetism limiting portion is disposed in a portion of the second magnetic circuit that does not overlap the third magnetic circuit.

An electromechanical circuit breaker comprising a main contact pair comprising a first main contact disposed on a first main contact bridge; an auxiliary contact pair comprising a first auxiliary contact disposed on a first auxiliary contact bridge, the first auxiliary contact bridge being connected in parallel to the first main contact bridge and wherein the auxiliary contact pair comprises a material that has a higher melting point than a material of the main contact pair; a first armature configured to move the first main contact bridge; a second armature configured to move the first auxiliary contact bridge, wherein the first and second armatures are configured such that the auxiliary contact pair opens after the main contact pair opens, and the auxiliary contact pair closes before the main contact pair closes.