A over-current protection device includes a positive temperature coefficient (PTC) polymeric element having two opposite surfaces, two electrodes respectively connected to the surfaces of the PTC polymeric element, and a power-free trip indicator disposed on at least one of the electrodes for sensing temperature of the over-current protection device.

The present disclosure relates to a power supply device for a protective relay. The power supply device comprises a power circuit for supplying a power to the control circuit, wherein the power circuit includes: a semiconductor switch element having an input terminal connected to a first node for receiving a direct current, and an output terminal connected to a reference node, wherein the reference node has a voltage lower than a voltage of the first node; and a first voltage drop element disposed between the first node and a second node, wherein the second node is connected to a switching terminal of the semiconductor switch element.

An electronic protection circuit includes a resettable fuse such as a positive temperature coefficient (PTC) thermistor or polymer PTC device. The resettable fuse enters a high-resistance tripped state in response to an overcurrent condition. One or more electrically controllable switches are placed in series with the resettable fuse. A monitoring and control circuit monitors voltage across the resettable fuse and to opens the switches when the voltage is outside of a predetermined range. The switches can remain open after the overcurrent event is resolved in order to allow the resettable fuse time to reset.

The invention proposes a wiper blade (10) of a motor vehicle, comprising a heating electrical circuit (30) comprising at least one heating resistive element, which is connected to terminals (36) for supplying electric current, and a component for regulating the electric power supply current, which is a resettable fuse with a positive temperature coefficient (50), known as a PTC fuse. The PTC fuse (50) is, for example, a surface-mounted component, known as a CMS component, which is electrically connected to two belonging electrical connecting areas (44, 46).

A device for controlling a pre-charge current generated when electrically connecting a first terminal and a second terminal, according to one embodiment of the present invention, may comprise: a switch for controlling a magnitude of a current flowing between the first terminal and the second terminal; a first resistor for generating a base voltage of a first transistor in proportion to a magnitude of the pre-charge current flowing between the first terminal and the second terminal; the first transistor for limiting the magnitude of the pre-charge current when a voltage generated by the first resistor is equal to or greater than a predetermined threshold voltage; a photocoupler for receiving, in a state insulated from a first power source, an optical signal from the first power source and supplying power; a capacitor charged by the power supplied by the photocoupler; a second transistor for controlling the magnitude of the pre-charge current on the basis of a charging voltage of the capacitor; and a second resistor for controlling an operating time of the second transistor along with the capacitor.

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 rotary connector apparatus includes: a ring-shaped fixed member; a ring-shaped rotating member rotatably fitted to the fixed member; a flexible flat cable housed in a housing space formed by the fixed member and the rotating member, the flexible flat cable having a plurality of wires, one end of the flexible flat cable being fixed to the fixed member and another end thereof being fixed to the rotating member, wherein a first connector housing attached to the fixed member accommodates a plurality of electrically conductive paths that respectively connect a plurality of first terminals to the plurality of wires at said one end of the flexible flat cable, and at least one of the plurality of electrically conductive paths is configured to removably receive a protection device so as to protect the path from overcurrent.

The present disclosure relates to a power supply device for a protective relay. The power supply device comprises a power circuit for supplying a power to the control circuit, wherein the power circuit includes: a semiconductor switch element having an input terminal connected to a first node for receiving a direct current, and an output terminal connected to a reference node, wherein the reference node has a voltage lower than a voltage of the first node; and a first voltage drop element disposed between the first node and a second node, wherein the second node is connected to a switching terminal of the semiconductor switch element.

An over-current protection device is a hexahedron comprising an upper surface, a lower surface and four lateral surfaces. The over-current protection device comprises a PTC device, a first insulating layer, a first electrode layer and a second electrode layer. The PTC device comprises a first conductive layer, a second conductive layer and a PTC material layer laminated therebetween. The first conductive layer comprises a first conductive section and a second conductive section separated by at least one trench. The first insulating layer is disposed on the first conductive layer. The first electrode layer is disposed on the first insulating layer and electrically coupled to the first conductive section. The second electrode layer is disposed on the first insulating layer and electrically coupled to the second conductive section. The trench comprises a primary portion not parallel to a longitudinal direction of the first and second electrode layers.

A composite circuit protection device includes a positive temperature coefficient (PTC) component, a voltage-dependent resistor, a first conductive lead and a second conductive lead. The PTC component includes a PTC polymeric layer, and first and second electrode layers respectively disposed on two opposite surfaces of the PTC polymeric layer. The voltage-dependent resistor is connected to the second electrode layer of the PTC component. The first and second conductive leads are respectively bonded to the first electrode layer of the PTC component and the voltage-dependent resistor. The PTC component has a rated voltage ranging between 40% and 200% of a varistor voltage of the voltage-dependent resistor.