A method of making printed circuit board vias using a double drilling and plating method is disclosed. A first hole is drilled in a core, the first hole having a first diameter. The first hole is filled and/or plated with an electrically conductive material. A circuit pattern may be formed on one or two conductive layers of the core. A multilayer structure may then be formed including a plurality of cores that also include pre-drilled and plated via holes, wherein at least some of the pre-drilled and plated via holes are aligned with the first hole. A second hole is then drilled within the first hole and the aligned pre-drilled and plated holes, the second hole having a second diameter where the second diameter is smaller than the first diameter. A conductive material is then plated to an inner surface of the second hole.

Fuse assemblies are disclosed. In one implementation, a fuse assembly may be disposed that includes a first portion of the second portion. The first portion may be formed of a first metal. The second portion may be formed of a second metal different from the first metal. The second metal may be copper, and the copper may be tin plated or silver plated.

An electromagnetic relay including: an electromagnet; a movable spring having a movable contact; a first terminal to which one end of the movable spring is connected; a second terminal having a fixed contact opposite to the movable contact; an actuator that rotates by excitation of the electromagnet, rotates the movable spring, and causes the movable contact to come in contact with the fixed contact or to separate from the fixed contact; a nonmagnetic card to be attached to the actuator; a plurality of magnetic members that sandwich the movable contact and the fixed contact, and apply a magnetic flux to the movable contact and the fixed contact to extend an arc; and a permanent magnet attached between the magnetic members.

Disclosed is a Battery Disconnect Unit that is good in assemblability and couplability because a middle cover accommodated in a lower case stably supports a relay terminal and a guide bar and a hood structure are applied to the middle cover. The BDU is disposed between a battery and an inverter to stably supply or break power of the battery to a power system of a vehicle. The BDU includes a lower case provided in a box shape with a top opened and a middle cover accommodated into and coupled to the lower case to press the relay terminal. A relay terminal hole into which a relay terminal is fitted is disposed on a bottom of the lower case, and an electric component is mounted on a top of the middle cover. A first fixing hook capable of being fastened to the lower case is provided in the middle cover.