The invention relates to a disconnection and switch-over device for overvoltage protection, particularly for DC systems, comprising at least one arresting element, and a thermal cut-off point incorporated into the electrical interconnect path of the arresting element, the thermal cut-off point comprising a movable mechanically prestressed conductor element that moves from a first position to a second position in the event of a cut-off, and when the second position is reached, an electrical switch-over to a safety device is generated, and the thermal cut-off point is formed by the movable conductor element and a stationary contact element, the movable conductor element being attached to the stationary contact element by a thermally releasable means. According to the invention, a completely electrical cut-off of the arresting element regarding the interconnect path only occurs when the movable conductor element has gone beyond the second position and has reached a third position, the safety device being arranged in series with the arresting element and the movable conductor element being designed as a wiper or sliding contact in relation to the second position, the second position being created by a bypass end point.

Provided herein are thermally protected varistor (TPV) devices including a varistor body and a terminal assembly directly coupled together. The terminal assembly may include a housing, wherein an opening is provided in a base of the housing. A lead is coupleable with the varistor body via a thermal linking material positioned within the opening of the base, the thermal linking material operable to maintain direct physical contact with the lead when the thermal linking material is below a melting point. The terminal assembly may further include a shield slidable within the housing between a first position and a second position, wherein in the first position the shield is positioned adjacent the thermal linking material, and in the second position the shield is positioned between the lead and the second side of the varistor body. The shield includes a tab for releasably coupling the shield to the housing.

An electrical protection component having a short-circuit device is disclosed. In an embodiment an electrical protection component includes a short-circuiting device including a surge arrester including electrodes and a thermal short-circuiting device including a clip, a first section of which is snapped onto the surge arrester and a second section of which comprises a short-circuiting link, wherein the short-circuiting link of the clip is spaced apart from at least one of the electrodes by a fusible element, wherein the short-circuiting link electrically conductively connects two of the electrodes to one another when the fusible element melts, and wherein the fusible element has a melting point of at least 300 degrees Celsius.

A surge suppression circuit for a track circuit is provided. The surge suppression circuit comprises a first surge protection device including a first pair of silicon avalanche diodes and a second surge protection device including a second pair of silicon avalanche diodes. The first surge protection device is connected on a first connection line between a first terminal of a railroad signaling electronic equipment to be protected from a surge and a first terminal of a first rail of two physical rails. The second surge protection device is connected on a second connection line between a second terminal of the railroad signaling electronic equipment and a second terminal of a second rail of the two physical rails. The first surge protection device and the second surge protection device are connected to an earth ground terminal.

An electrostatic-discharge (ESD) protection circuit is provided. The circuit includes an I/O terminal coupled for receiving a signal having a negative voltage relative to a voltage supply terminal. An ESD transistor is formed in an isolated well. The transistor includes a control electrode and a first current electrode coupled to the I/O terminal. The isolated well is configured as a body electrode of the transistor. An ESD diode includes an anode electrode coupled to the voltage supply terminal and a cathode electrode coupled to a second current electrode of the transistor.

A varistor (50) comprising: a feed-through conductor (52) and a varistor disc (72) interposed between, and electrically connected to, conductor layers disposed on opposite surfaces of the varistor disc (72), the conductor layers being electrically isolated from one another; wherein the varistor disc (72) comprises a through aperture (60) through which the feed-through conductor extends; a first one of the conductor layers is electrically connected to the feed-through conductor; a second one of the conductor layers is, in normal use, permanently electrically connected to ground the varistor (50). This configuration enables one side of the disc (72) to be connected to the feed-through terminal, and the other side of the disc (72) to be connected to a ground plane, such as an earthed bulkhead of a wall or cabinet, via a metal plate forming part of the varistor (50) housing.

The present disclosure provides a method and device for overvoltage protection. Specifically, the present disclosure provides an overvoltage protection device which provides a feedback loop for electronic components such as amplifiers and digital to analog converters which require feedback. The overvoltage protection device also includes overvoltage switches in both the signal and feedback channels, which may be opened by a fault detector in the event of an overvoltage. The device also includes an overvoltage feedback channel coupled between the signal and feedback channels, and which also includes a switch which may be closed in the event of an overvoltage event. As such, the overvoltage device provides a closed loop feedback channel during an overvoltage event.

An electrical connector provided with a varistor, and to a protection device for incorporation into an electrical connector and having a varistor comprising at least two pins including a first pin which is a live (502) or neutral (504) pin and a second pin which is an earth pin (506), the first and second pins (502, 504, 506) extending through respective apertures (512) in a varistor plate (514) which has first and second faces, wherein a first conductive layer on the first face of the varistor plate (514) connects electrically to the first pin (502, 504) and a second conductive region on the second face of the varistor plate connects electrically to the second pin (506), so that in response to an excessive voltage across the first (502, 504) and second (506) pins the varistor plate will conduct electricity between the first (502, 504) and second (506) pins. The arrangement can easily be adopted in connectors conforming to existing standards, such as existing mains electrical plugs (500).

An electronic apparatus is provided. The electronic apparatus according to an embodiment includes a main circuit unit, a power source supplier configured to generate power, and supply the generated power to the main circuit unit, and a surge protector disposed between the main circuit unit and the power source supplier, the surge protector being configured to, based on a surge occurring from the power source supplier, perform a clamping operation on power output from the power source supplier at a first voltage level, wherein the power source supplier is further configured to, based on the clamping operation of the surge protector at the first voltage level being stopped, perform a clamping operation on the generated power at a second voltage level greater than the first voltage level.

A power control device includes: an output voltage controller configured to control an output voltage based on a feedback voltage corresponding to the output voltage; and an overvoltage protector configured to continue or stop the operation of the output voltage controller based on a first detection result of whether the output voltage has exceeded an output voltage threshold value and a second detection result of whether the feedback voltage has fallen to or below a feedback voltage threshold value.