Abstract: A power system bus total overcurrent system is used with a part of a power system which includes two buses and first and second power line portions which extend between them. A protective relay system includes protective relays for each of the first and second power line portions, located near the two buses, wherein the relays determine the total current into and out of each bus. The bus total overcurrent system includes first and second communication lines between each pair of relays and another communication line which extends between the first and second communication lines. In a current balance arrangement, the relays measure difference current using the same communication line arrangement between the two pairs of relays to determine a fault condition. Fault determinations are made in each case by the protection algorithms from total and difference currents.

Abstract: The distribution transformer is installed in a station having N phases, at least N-1 phases being equipped on the high-voltage side of the transformer with respective current-limiting fuses capable of blowing in the event of a dead short circuit between the phases. The protection system includes: at least one fault detector for detecting faults on the basis of at least one of the following indicators: pressure in the tank, level of the dielectric, or temperature of the transformer; a short-circuiter acting on all the phases situated upstream from the high-voltage windings, said short-circuiter being capable of being triggered by said fault detector to establish a dead short circuit between the phases; and on at least N-1 phases, a detector for detecting an abnormal current upstream from the transformer, said detector being associated with a controller for controlling said short-circuiter.

Abstract: An overvoltage protection device for an electronic apparatus having a plug-in device which has at least one plug-in element and is designed for insertion into a housing of the electronic apparatus. In overvoltage protection in which there is no need for any additional shielding measures from the electronics, a protection board which has a spark gap in order to dissipate overvoltages is arranged on the plug-in element.

Abstract: A protective relay system for a power system having protective relays at specific locations in the system. Each location has specific setting information for the relay for operation of the relay at that location. Each relay in the protective relay system includes in memory all of the setting information for all of the locations in the power system. Connection of the relay to a key identifier member at a desired location, in one embodiment, provides an identification of that location to the relay. The identification may also be provided by a system computer to which the relay is connected at the desired location. The relay uses the information to obtain the correct setting information for the desired location from its memory for proper protection operation at the desired location, eliminating programming of replacement relays.

Abstract: An electrostatic discharge protection apparatus for a circuit board is described. The electrostatic discharge protection apparatus has a nonconductive layer and a conductive layer. The conductive layer is used to dissipate electric charges accumulated on the pointed ends of the circuit board, and thus improves the electrostatic discharge protection ability of the circuit board.

Abstract: An apparatus and method for providing redundant protection to a fault detection/interruption circuit, thereby ensuring safe operation even in the case of a failure of the primary fault detection/interruption means. Upon the occurrence of a failure in the primary circuit interruption means, a secondary circuit breaker, or in some embodiments, a redundant primary circuit breaker release mechanism, serves to remove power from a protected outlet or output conductors.

Abstract: The present invention is directed to a condition monitoring system for determining internal motor fault information. Voltage and current data are acquired from an induction machine in operation. Reactive and real power delivered to the induction machine is then determined from the voltage and current data. An inspection of the frequency spectrum of the real power as well as the reactive power is then used to ascertain load and motor condition. Specifically, an analysis of the frequency spectrum of the reactive power may be inspected for information relating to an internal motor fault whereas the frequency spectrum of the real power may be inspected for information relating to motor-driven or load faults.

Abstract: A circuit board includes a power switch operable so as to generate a trigger signal upon actuation, a card slot adapted for connecting with a video card, and a controller coupled electrically to the power switch and the card slot. The controller detects connection of the video card to the card slot and further detects operating voltage of the video card. The controller inhibits the power switch from generating the trigger signal upon detection that the operating voltage of the video card that is connected to the card slot is higher than a predetermined voltage.

Abstract: The invention related to a three-in-one protection circuit against out-rush current, short circuits and overloading. A second power source connected to the output side of a transformer in a power supply is used as a power source when the protection function is activated. This is in order to provide the power source for a protection circuit when a short circuit happens at an output end. A current sensor connected to the output side of the transformer is used to sense the occurrence of an overload current and a timer is used to set the time that a specific out-rush current can be yielded to allow and limit the yielding of the out-rush current. Therefore, an executor for activating protection function can be used in the above-mentioned three-in-one protection circuit simultaneously at the same circuit.

Abstract: The invention is concerned with a resistive fault current limiter (FCL) based on thin superconducting films. The FCL comprises constrictions (2) with a reduced critical current, separated by connecting paths (3). Upon occurrence of a fault current, the former turn resistive simultaneously and build up a resistance which allows the applied voltage to drop entirely only over the constrictions. Only at a later stage, the connecting paths become resistive and dissipate energy. The thickness and width of an electrical bypass determine said normal resistivities of the constrictions and the connecting paths.

Abstract: Data memories are used to represent the characteristic values of the properties of the circuit-breaker and the associated current transformer. A cable harness uses a writeable electronic memory module which is inserted into one of the interconnecting cables between the current transformer(s) and the overcurrent trip as the data memory.

Abstract: A ground fault interrupter apparatus is provided that employs a switching device that is operated in two stages. The first stage operates a solenoid in order to close the contacts and preferably provides coupling between the load and the power source. The second stage maintains the coupling, however, drawing less current and power from the internal devices of the apparatus. Accordingly, the fault interrupter meets various standards for the time required to open and close the contacts as well as keeping the dissipated heat from the device within the required range.

Abstract: A circuit for suppressing transients in a voltage regulator due to a load step transient in the demand of the load. The circuit includes a suppressor element that is placed in the current path of the inductor of the switching regulator in response to a determination of an over voltage condition. The suppressor element pulls the voltage level of one side of the inductor below a particular potential, such as, e.g., system ground. Examples of suppressor elements that may be used include zener diodes, diodes, capacitors, resistors, and negative voltage sources. When the current through the inductor has subsided to a particular level, the suppressor element may be removed from the inductor current path, wherein the energy stored in a bulk filter capacitor may be drained through the inductor to the system ground. The suppressor circuit may be used in a information handling system or other type of electronic system.

Abstract: The present invention relates to lightning protection, and in particular, to lightning protection using vacuum plasma. The lightning protection of the present invention impairs an electric field created by an atmospheric condition, such as a charged cloud, by polarizing vacuum plasma that is under the effect of the electric field. The polarized plasma neutralizes or diminishes the electric field in the proximity of a protected object and thus prevents the electric field from reaching a sufficient level where the air near the protected object fails to act as an insulator. In this way, the lightning strike is prevented from hitting an object surrounded by or in close proximity to the plasma.

Abstract: An arc fault protection device uses two detection levels for detecting both parallel and series arc faults. When a sensed load current is below a predetermined level, a first set of characteristics indicative of a series arc fault are compared to a sensed di/dt signal. When the sensed load current exceeds the predetermined level, a second set of characteristics indicative of a parallel arc fault are compared to the sensed di/dt signal. This approach allows more time to evaluate a potential series arc fault than is permitted when evaluating a potential parallel arc fault.

Abstract: The invention is directed to a surge arrestor having a middle electrode and at least one outer electrode, in which an electrically conductive spring clip is secured to the middle electrode and exerts a spring power on the outer electrode; in which an electrical component part that is non-conductive at the trigger voltage of the surge arrestor and generates heat given a flow of current is arranged between the spring clip and the outer electrode; in which the spring clip lies against an electrically conductive contact element that is secured to a spacer element using a fusible mass and that is spaced from the outer electrode; and in which, when the fusible mass melts, the contact element is pressed against the outer electrode by the spring clip. The trigger mechanism has the advantage that it reacts very quickly and thereby reduces the formation of sparks and the fire hazard as well.

Abstract: The invention provides an electro-adhesion device (10) including a base (12) and first (14) and second (16) banks of thin electrically conductive electrodes (18) located apart from each other on a side of the base (12). The electro-adhesion device (10) also includes an insulating cover (20) over the first (14) and second (16) banks so that the outer side of the insulating cover (20) defines an electro-adhesion surface so that, in use, when the electrodes (18) are energized and an object to be attracted is placed adjacent the insulating cover (20), the object is attracted to the insulating cover (20) by a suitably high adhesion force. An outer surface (24) of each of the electrodes (18) has a linear border on one side and a sinusoidal border on an opposite side so that the width of each electrode (18) varies sinusoidally lengthwise along the electrode (18).

Abstract: Multiple embodiments of a personal defense device each include an electrical stun circuit and electrodes with a structure adapted for use as an impact weapon as well, and further include a radially disposed flashlight or signal light therewith. The electrical circuitry for the stun apparatus may be formed of flexible circuit material with dual circuit paths between each component, for reliability and resistance to damage due to impact forces incurred when the device is used as an impact weapon. A second, normally closed interrupter switch may be provided for the stun circuit, with the user of the present device being required to hold the interrupter switch in order to keep the stun circuitry from operating when the master switch is turned on. The end opposite the handle may include a series of impact ribs with cutting blades removably installable thereon, to produce non-lethal cuts in an assailant during an attack.

Abstract: A panelboard configured for distributing electricity from a power source, the panelboard comprising circuitry for distributing the electricity from the power source, the circuitry comprising a plurality of branch circuits for distributing electricity to associated loads; a plurality of branch circuit breakers, each branch circuit breaker intermediate the power source and the plurality of branch circuits; and an electronic control module for controlling the main circuit breaker and the plurality of branch circuit breakers, the electronic control module provides a protection function and a monitoring function of the circuitry, each branch circuit breaker of the plurality of branch circuit breakers includes; a pair of separable contacts, an electromagnetic actuator in electrical communication with the electronic control module for operably controlling the pair of separable contacts, and a current transformer configured to sense current on the circuitry to one of the associated loads.

Abstract: An electrostatic discharge (ESD) protection circuit formed on a P-type substrate. The ESD protection circuit is disposed between a bonding pad and an internal circuit formed on a P-type substrate, and has a P-type metal-oxide semiconductor (PMOS) and an N-type metal-oxide semiconductor (NMOS). The PMOS has a first doped regionformed below a P+ guard ring of the PMOS and a well pick-up of the PMOS. The NMOS has second doped regionformed below a N+ guard ring of the NMOS and a well pick-up of the NMOS. An equivalent zener diode is formed on the P-type substrate. A breakdown of the equivalent zener diode restricts the PMOS or the NMOS from producing a snapback breakdown.