A glass sealed thermistor having a shock absorbing structure includes: a thermistor device whose resistance value changes according to temperature; a glass sealing layer that hermetically protects a head and a contact electrode of the glass sealed thermistor; a pair of conductive supporters having an electrical conductor function and a thermistor device support function; a shock absorbing structure formed by surrounding the pair of conductive supporters adjacent to the glass sealing layer; and a coating layer is coated on the glass sealing layer with polymer material.

A circuit protection device including a primary fuse, and a positive temperature coefficient (PTC) device and a secondary fuse electrically connected in series with one another and in parallel with the primary fuse, the secondary fuse formed of a quantity of solder disposed on a dielectric surface, wherein the dielectric surface exhibits a de-wetting characteristic relative to the solder such that, when the solder is melted, the solder draws away from the dielectric surface to create a galvanic opening.

A circuit protection device including a primary fuse, and a positive temperature coefficient (PTC) device and a secondary fuse electrically connected in series with one another and in parallel with the primary fuse, the secondary fuse formed of a quantity of solder disposed on a dielectric surface, wherein the dielectric surface exhibits a de-wetting characteristic relative to the solder such that, when the solder is melted, the solder draws away from the dielectric surface to create a galvanic opening.

In an embodiment a thermal varistor protection device includes a casing, a varistor embedded in the casing, wherein the varistor includes a first metallization electrode, which is only partly covered by an insulating material of the casing to allow an electrically conductive connection, a first terminal wire electrically conductively connected to the first metallization electrode of the varistor and a contact element electrically conductively connected to the first metallization electrode of the varistor in a region where the varistor is not covered by the insulating material, wherein the contact element is pre-stressed to ensure a fast separation of the contact element and the first metallization electrode when the electrically conductive connection between the contact element and the first metallization electrode becomes loose.

In an embodiment a thermal varistor protection device includes a casing, a varistor embedded in the casing, wherein the varistor includes a first metallization electrode, which is only partly covered by an insulating material of the casing to allow an electrically conductive connection, a first terminal wire electrically conductively connected to the first metallization electrode of the varistor and a contact element electrically conductively connected to the first metallization electrode of the varistor in a region where the varistor is not covered by the insulating material, wherein the contact element is pre-stressed to ensure a fast separation of the contact element and the first metallization electrode when the electrically conductive connection between the contact element and the first metallization electrode becomes loose.

In an embodiment a thermal protection device includes a housing, a varistor partly embedded in the housing, wherein the housing electrically insulates the varistor, and wherein the varistor includes a partly uninsulated contact surface, an inner wall of insulating material arranged adjacent to the contact surface of the varistor, a window in the inner wall configured to allow an electrical connection of the contact surface of the varistor in an operational state of the thermal protection device and a moveable insulation block configured to cover the window in the inner wall to insulate the varistor in a region of the window of the inner wall in a fault state of the thermal protection device.

In an embodiment a thermal protection device includes a housing, a varistor partly embedded in the housing, wherein the housing electrically insulates the varistor, and wherein the varistor includes a partly uninsulated contact surface, an inner wall of insulating material arranged adjacent to the contact surface of the varistor, a window in the inner wall configured to allow an electrical connection of the contact surface of the varistor in an operational state of the thermal protection device and a moveable insulation block configured to cover the window in the inner wall to insulate the varistor in a region of the window of the inner wall in a fault state of the thermal protection device.

An externally-controllable thermal tripping device comprising a voltage dependent resistor including a voltage dependent resistor chip; a thermal tripper including a tripping electrode; and a controllable heating element. The tripping electrode is connected to an electrode of the voltage dependent resistor chip through a meltable welding material, and the controllable heating element is controlled by an external control device to generate heat and transmit generated heat to a commissure of said welding material to melt said welding material and electrically disconnect the tripping electrode from the voltage dependent resistor chip.

A thermally protected varistor includes a varistor chip, a temperature fuse, and a lead line, wherein the varistor chip includes a first conductive layer and a second conductive layer, and the lead line includes a first lead line, a second lead line, and a third lead line. One end of the first lead line is connected to the first conductive layer, and the other end of the first lead line is led out. A first end of the temperature fuse is led out as the second lead line, and a second end of the temperature fuse is connected to the second conductive layer. One end of the third lead line is connected to the second conductive layer, and the other end of the third lead line is led out. The temperature fuse is an axial temperature fuse and is tightly attached to the varistor chip.

In a method for manufacturing a shunt resistor, a resistor plate with a first side surface and a second side surface opposite to each other is provided. A first electrode plate and a second electrode plate are respectively pressed onto the first side surface and the second side surface, thereby forming a first connection surface between the first electrode plate and the resistor plate, and a second connection surface between the second electrode plate and the resistor plate. A first conductive module is placed on opposite ends of the first connection surface, and a second conductive module is placed on opposite ends of the second connection surface. Current is applied to the first and second connection surfaces via the first and second conductive modules respectively to weld the first electrode plate and the resistor plate, and to weld the second electrode plate and the resistor plate.