A fuse control system and method using a defective mode detection, in which an overcurrent protective fuse and a signal fuse capable of performing a function under various conditions in order to protect a circuit are integrated. Thus, it is possible to protect the circuit even in states such as overvoltage, a high temperature, a low temperature, and other dangerous states in addition to an overcurrent state and a short-circuited state. In addition, it is possible to reduce a wide design space and design cost which result from various kinds of fuses being used in series, and to simplify a circuit configuration. Consequently, since circuit resistance is reduced, it is possible to have a positive influence on a battery.

A protection device comprises a substrate, a fusible element, a flux and an insulating cover. The fusible element is disposed on the substrate and connects to a power line of an apparatus to be protected. The flux is disposed on the fusible element. The insulating cover is secured on the substrate to form a room for receiving the fusible element. The insulating cover has a bottom surface facing the substrate, and a plurality of protrusions are formed and distributed on the bottom surface to hold the flux in place.

An arc-preventing fast-breaking surge protection device is disclosed. In one of implement, surge protection device includes an arc-preventing assembly consisted of an arc-preventing catapult and an elastic element, comprising a voltage sensitive assembly, a response switch assembly, a thermosensitive element, an inner shell and an outer cover. The voltage sensitive assembly is tightly coupled with the response switch assembly. When the instantaneous surge voltage in circuits causes the voltage sensitive assembly to continuously heat up due to the fault short-circuit current, the response switch assembly causes the arc-prevent assembly to be catapulted and separated by the thermal coupling response of the thermosensitive element, meanwhile the response switch assembly is conceal by the arc-preventing assembly, thus preventing the arc generated when the switch is s catapulted and separated from forming a short-circuit and an overload, thus effectively avoiding fire and explosion hazards and further preventing secondary damage of electronic devices.

A switch device capable of safely opening or short-circuiting an electrical circuit in response to an abnormality such as wetting with water or liquid leaking from a battery is provided. The device includes a conductor connected to an external circuit, and a reaction part including a liquid-soluble material which opens the conductor and the external circuit and which dissolves on contacting a liquid entering the device interior to electrically connect the conductor and the external circuit.

A protection device comprises a substrate, a fusible element, a flux and an insulating cover. The fusible element is disposed on the substrate and connects to a power line of an apparatus to be protected. The flux is disposed on the fusible element. The insulating cover is secured on the substrate to form a room for receiving the fusible element. The insulating cover has a bottom surface facing the substrate, and a plurality of protrusions are formed and distributed on the bottom surface to hold the flux in place.

A redundant fault protection architecture for a DC electrical system with a hybrid relay sensing current on a DC rail as primary protection, and a pyrofuse, either self-triggering or externally triggered, as secondary protection. The pyrofuse is set to trigger after a delay to enable the hybrid relay to clear the fault (overcurrent). If the hybrid relay fails to clear the fault within a certain time duration, the pyrofuse subsequently is triggered and clears the fault.

A circuit protection system including at least one fuse including a fuse element, at least one inductive heating element operable to heat the fuse element, at least one control module in communication with the inductive heating element, and at least one current detection device coupled to said control module. The control module is configured to operate the inductive heating element and cause the fuse element to open in response to a predetermined current condition.

A fuse element includes a low-melting-point metal plate, a first high-melting-point metal layer, and a second high-melting-point metal layer. The low-melting-point metal plate has a first main surface, a second main surface, a first side surface, and a second side surface. The first main surface and the second main surface face each other. The first side surface and the second side surface face each other and each connect the first main surface and second main surface. The first high-melting-point metal layer is disposed on the first main surface and second main surface. The second high-melting-point metal layer is disposed on the first side surface and second side surface. The fuse element has a cut-out portion in which at least a portion of the second high-melting-point metal layer is cut out.

A reflowable thermal fuse including a fuse body, a conductive composite element disposed within the fuse body, first and second conductive terminals connected to the conductive composite element and extending out of the fuse body, a removable barrier covering a surface of the conductive composite element and in electrical communication with the first and second conductive terminals, and a solvent element disposed on the removable barrier and separated from the conductive composite element by the removable barrier, wherein the removable barrier has a fusing temperature that is greater than a reflow temperature of the reflowable thermal fuse.

A protective element includes a base substrate, a fusible conductor, a heater, and a heater-attached substrate. The base substrate has a first electrode and a second electrode formed thereon, the first electrode and the second electrode each being connected to an external circuit. The fusible conductor is supported on a first surface thereof by the base substrate and connected to the first electrode and the second electrode. The heater is configured to fuse the fusible conductor by generating heat. The heater-attached substrate has the heater provided thereon. The fusible conductor has one contact with the heater-attached substrate and the one contact is positioned on a second surface of the fusible conductor, which is an opposite surface to the first surface.