An ESD protection device of the present disclosure includes a ceramic multilayer structure inside which a cavity portion is formed, at least one pair of discharge electrodes arranged inside the ceramic multilayer structure, and outer electrodes formed on the surface of the ceramic multilayer structure and connected to the discharge electrodes, wherein the pair of discharge electrodes are arranged in such a way that one end-face of one discharge electrode and one end-face of the other discharge electrode are opposed to each other through the cavity portion, and the cavity portion is formed as a single cavity occupying a region between the opposed end-faces, regions along other end-faces connected to the opposed end-faces via corner portions, and, on first principal surfaces, regions along the opposed end-faces and regions along the other end-faces.

An ESD protection device of the present disclosure includes a ceramic multilayer structure inside which a cavity portion is formed, at least one pair of discharge electrodes arranged inside the ceramic multilayer structure, and outer electrodes formed on the surface of the ceramic multilayer structure and connected to the discharge electrodes, wherein the pair of discharge electrodes are arranged in such a way that one end-face of one discharge electrode and one end-face of the other discharge electrode are opposed to each other through the cavity portion, and the cavity portion is formed as a single cavity occupying a region between the opposed end-faces, regions along other end-faces connected to the opposed end-faces via corner portions, and, on first principal surfaces, regions along the opposed end-faces and regions along the other end-faces.

An apparatus includes a surge protection device, a current sensor configured to sense a current through the surge protection device, and a surge discriminator circuit coupled to the current sensor and configured to discriminate among a plurality of surge levels for the surge protective device responsive to the sensed current. The current sensor may include a current transformer configured to generate a secondary current responsive to the sensed current and the surge discriminator circuit may be configured to discriminate among a plurality of surge levels responsive to the generated secondary current.

The invention concerns a device for protection against transitory overvoltages, comprising: a varistor; a discharge tube; a thermofusible soldering securing a first electrode of the discharge tube and a first electrode of the varistor, the thermofusible soldering being a conductor of electricity and being able to melt beyond a temperature threshold when the varistor or the discharge tube heats up; the second electrode of the varistor being designed to be connected to a first electrical line and the second electrode of the discharge tube being designed to be connected to a second electrical line; a restoring element exerting a restoring force tending to move the first electrode of the varistor away from the first electrode of the discharge tube in order to allow a separation between the first electrode of the varistor and the first electrode of the discharge tube during a melting of the thermofusible soldering.

A spacing-assured gas discharge tube assembly is installed on a printed circuit board, which may be part of a motor controller. The discharge tube assembly includes a tube body and an electrostatic spacing shield disposed at least partially around the tube body. The shield is configured to prevent close physical proximity of adjacent structures having electrostatic fields that may alter the breakdown voltage of the tube body.

A spacing-assured gas discharge tube assembly is installed on a printed circuit board, which may be part of a motor controller. The discharge tube assembly includes a tube body and an electrostatic spacing shield disposed at least partially around the tube body. The shield is configured to prevent close physical proximity of adjacent structures having electrostatic fields that may alter the breakdown voltage of the tube body.

Disclosed in the present invention is a novel overvoltage protective device for lightning protection, comprising a first varistor, a second varistor, a PTC Thermistor, and lead-out terminals. The first varistor and the PTC Thermistor are connected in parallel, and then further connected in series with the second varistor to form a single port combined circuit. The surge-withstand capability of the first varistor is higher than the surge-withstand capability of the second varistor. At least one of the two lead-out terminals of the single port combined circuit is a thermally-conductive end with low thermal resistance. The second varistor is thermally coupled to the PTC Thermistor. The thermally-conductive end with low thermal resistance is thermally coupled to one or both of the second varistor and the PTC Thermistor.

A wire harness includes a wire portion having three wires arranged in the same direction, connectors connected to both end portions of the wire portion, a middle portion installed in an intermediate position of the wire portion between the connectors, a wire-side surge reducing section provided in the wire portion, a connector-side surge reducing section provided in each of the connectors, and a middle portion-side surge reducing section provided in the middle portion.

A wire harness includes a wire portion having three wires arranged in the same direction, connectors connected to both end portions of the wire portion, a middle portion installed in an intermediate position of the wire portion between the connectors, a wire-side surge reducing section provided in the wire portion, a connector-side surge reducing section provided in each of the connectors, and a middle portion-side surge reducing section provided in the middle portion.

The invention relates to an overvoltage protection device with a short-circuit function for protecting installations and persons for low-voltage installations, wherein at least one overvoltage protection element and a thermally activatable short-circuit device are arranged in a common housing. The device is designed to be inserted into an NH fuse part, and the common housing is designed with contact blades so as to be spatially analogous to a NH fuse link.