Abstract: A circuit breaker is for interrupting an electric current circuit when current and/or current time period thresholds are exceeded. The circuit breaker includes at least one control unit, to which energy is supplied by an energy converter. A primary winding of the energy converter is formed by a conductor of the electric current circuit. The core of the energy conductor surrounding the electric current circuit conductor is used as the primary winding. A secondary winding surrounds a section of the core. The secondary winding additionally surrounds an inductor core, arranged relative to the core using an insulating spacer element. The secondary winding and the inductor core are at least party magnetically shielded from the primary winding by a shielding plate guided through the core.

Abstract: A sensor for inductively measuring the current in a conductor flowing through a recess in a printed circuit board. Wire loops on the printed circuit board function as the inductive current sensor. Combined with a voltage measurement, the energy being dissipated in the conductor's load circuit can be determined and transmitted wirelessly. Control circuits can be integrated with the metering hardware to enable the remote modulation of the load's power. The inductive sensor(s) can be used to track differences between the load's supply and return currents. If a fault is detected, the circuit can be broken for safety, serving a ground fault circuit interruption (GFCI) purpose. The claimed invention can report measurements in real time, providing time series data for analyses sufficient to detect or identify an anomaly in the function and operation within a system's load or electrical power distribution network.

Abstract: Techniques are provided for low, or deep, dimming of a light-emitting diode (LED) load. In an example, a low dimming circuit can include a target current detector configured to provide an output indicative of a target current of a power stage of a pulse width modulated driver, and a control circuit configured to receive a PWM signal of the PWM LED driver, to control a first transition to a first state of a power switch of the power stage during an on-interval of a first PWM cycle of the PWM signal, and to control a second transition to the first state of the power switch using the output of the target current detector during an off interval of the first PWM cycle.

Abstract: An arc suppression device includes an AC to DC converter, a switch, a resistor and a controller. The switch is coupled between the AC to DC converter and a plasma chamber. The resistor is coupled in parallel with the switch. The AC to DC converter is configured to convert an AC voltage into a DC voltage for providing to the plasma chamber. The controller is configured to detect a unit-time rate of change (ROC) of a plasma current received by the plasma chamber. When the controller determines that the unit-time ROC of the plasma current is larger than a first unit-time ROC threshold, the controller controls the switch to electrically isolate the AC to DC converter and the plasma chamber to reduce the plasma current to a first current value through the resistor.

Abstract: The present invention relates to a 3 phase electric leakage current circuit breaker with electric shock protection having a first function of detecting a leakage current and operating a circuit breaker to break an electric path if a leakage current exceeds a tolerance and a second function of detecting a leakage current every half cycle intervals of a power source, subtracting two leakage currents detected before and after a half cycle interval from each other as a vector calculus to compute a leakage current change, and operating a circuit breaker to break an electric path if the leakage current change exceeds a tolerance. The former case corresponds to protection against a normal leakage current which gradually increases, and an allowable leakage current is several hundreds of mA. The latter case is for protection against electric shock to a human body when a leakage current abruptly changes due to electric shock to a human body or the like, and an allowable leakage current is several tens of mA.

Abstract: In one example, a circuit includes a first voltage converter and a second voltage converter. The first voltage converter is configured to convert a first voltage to a second voltage, determine whether the first voltage converter is operating in an unsafe state, and output an indication that the first voltage converter is operating in the unsafe state. The second voltage converter is configured to selectively activate a high side switch and a low side switch to convert the second voltage to a third voltage. In response to receiving the indication that the first voltage converter is operating in the unsafe state, the second voltage converter is further configured to activate the high side switch and the low side switch to establish an electrical path between the second voltage and a reference node of the circuit.

Abstract: A DC distribution board comprises, therein as internal devices, a circuit breaker 5 provided along each of branch lines branched from main wires of a direct-current power supply, and a controller 6 for controlling switching of the breaker 5. The circuit breaker 5 comprises: power connecting terminals t1, t2 connected to the main wires; load connecting terminals t3, t4 connected with wires from a load; a semiconductor switch device 57 provided along an electrical circuit between the terminals t1, t2 and the terminals t3, t4; a current sensing resistor 56 for detecting an electric current through the electrical circuit; and a arithmetic circuit 60 for turning the device 57 on or off according to an on/off control signal from the controller 6, and coercively turning the device 57 off when a current value obtained from a voltage across the resistor 56 exceeds a set current.

Abstract: A safety shut-off system and method for eliminating power to a load in the event of smoke detection. The system may comprise a device located at the appliance for detecting a signal from a smoke detector, and cutting power to the appliance only when the appliance is in use. The device may be synchronized with any standard smoke alarm signal to reduce the number of false positive shut-offs. The system may also comprise a smoke alarm hard-wired to a circuit breaker, for shutting off power to all appliances on a particular breaker upon receipt of a signal from the smoke alarm, and only when the appliances on the breaker are in use. The system may also have the ability to shut off one breaker, multiple breakers, or all breakers at different time increments to actively prevent and reduce the damages caused by fires.

Abstract: Devices, such as mobile devices, may be exposed to short circuit and output overload events. To protect against such events, mobile devices typically include current limit circuits. Some current limit circuits may involve user programmable function. User programmable function may need accurate current limit detectors. Various embodiments of the present invention include devices and methods for detecting one or more programmed current limits. Some embodiments allow for a user application to select among parallel or serial configurations of current detection circuitry. Each such configuration may include multiple resistive devices of different resistive values.

Abstract: System and methods are provided for monitoring a state of a switch element connecting a DC power supply to a load. A system includes a transformer having first and second windings, where a first end of the second winding electrically coupled to a first switch node of the switch element. The system also includes a transmit circuit configured for providing a waveform at the first winding and a sensor element having galvanically isolated input and output nodes for inducing a monitor signal at the output nodes in response to a signal at the input nodes. The system further includes a receive circuit coupled to the output nodes and configured for generating one or more output signals in response to the monitor signal. The system also includes capacitor elements for providing DC isolation for the second winding with respect to the first switch node and the sensor element.

Abstract: An aircraft power distribution system is disclosed that includes a power distribution box. A generator supplies power to the power distribution box, and a load receives power from the power distribution box. The power distribution box includes a board supporting plug-in pins receiving the power. A contactor is supported by the board to selectively providing power to a secondary power distribution connector supported on the board. The board includes power traces that are run within the board to connect the plug-in pins to the secondary power distribution connector. Protection and secondary power distribution circuitry is also supported by the board and connected to the contactors and/or power traces by control traces. The power and control traces eliminate loose wiring and harnesses.

Abstract: A fault current limiter (FCL) includes a series of high permeability posts for collectively define a core for the FCL. A DC coil, for the purposes of saturating a portion of the high permeability posts, surrounds the complete structure outside of an enclosure in the form of a vessel. The vessel contains a dielectric insulation medium. AC coils, for transporting AC current, are wound on insulating formers and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil in the corresponding high permeability core are opposing. There are insulation barriers between phases to improve dielectric withstand properties of the dielectric medium.

Abstract: An distributed electronic circuit (1), such as a transmission line or distributed amplifier, is disclosed comprising an input terminal (2), an output terminal (3), power supply lines (4,5), a sequence of sections (61, 62, 63, 64, 65), between the input terminal (2) and the output terminal (3), arranged to transfer an electrical signal from one section to another section; each section (61, 62, 63, 64, 65) comprising at least one Electro Static Discharge (ESD) protection component (9) configured to, upon occurrence of an ESD event, convey corresponding ESD currents to a power supply line (4, 5); and wherein the ESD components (9) of the respective sections (61, 62, 63, 64, 65) are selected such that, upon occurrence of an ESD event, at least one subsequent section (62, 63, 64, 65) is triggered before the first section (61).

Abstract: A circuit and method protect switching devices from alternating current overload. By protecting the switching devices from AC overload, the reliability of the equipment using the switching devices is improved, cost for repair is decreased and information regarding the cause of the AC overload is available.

Abstract: A fault current limiter (FCL) includes a series of high permeability posts for collectively define a core for the FCL. A DC coil, for the purposes of saturating a portion of the high permeability posts, surrounds the complete structure outside of an enclosure in the form of a vessel. The vessel contains a dielectric insulation medium. AC coils, for transporting AC current, are wound on insulating formers and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil in the corresponding high permeability core are opposing. There are insulation barriers between phases to improve dielectric withstand properties of the dielectric medium.

Abstract: A method for avoiding undesired, measurement error-induced protective tripping within a protection system of an HVDC transmission system. State variables of components of the HVDC transmission system are detected by first measuring devices to obtain a first set of measured values and by further measuring devices, which are designed in redundant fashion with respect to the first measuring devices, to obtain further sets of measured values. The first and further sets of measured values are supplied to a closed-loop control unit and a protective unit. The protective unit checks the first set of measured values for the presence of a risk of protective tripping by way of internal logic, and the closed-loop control unit regulates the HVDC transmission system as a function of one of the further sets of measured values.

Abstract: Electronic circuit breakers and systems for isolating a load from a power-supply unit are provided. One electronic circuit breaker includes a current sensor, a switching element coupled to the current sensor, and a switch controller coupled to the current sensor and the switching element. The switch controller is powered by the power-supply unit and is configured to switch OFF the switching element when the current sensor detects an amount of current from the power-supply unit greater than a predetermined amount. An electronic system includes a power-supply unit, a load, and the above-referenced electronic circuit breaker coupled to the power-supply unit and the load.

Abstract: A fault current limiter (FCL) includes a series of high permeability posts (1) for collectively define a core for the FCL. A DC coil (2), for the purposes of saturating a portion of the high permeability posts (1), surrounds the complete structure outside of an enclosure in the form of a vessel (3). The vessel (3) contains a dielectric insulation medium (4). AC coils (5), for transporting AC current, are wound on insulating formers (6) and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil (5) in the corresponding high permeability core are opposing. There are insulation barriers (7) between phases to improve dielectric withstand properties of the dielectric medium.

Abstract: Devices, such as mobile devices, may be exposed to short circuit and output overload events. To protect against such events, mobile devices typically include current limit circuits. Some current limit circuits may involve user programmable function. User programmable function may need accurate current limit detectors. Various embodiments of the present invention include devices and methods for detecting one or more programmed current limits. Some embodiments allow for a user application to select among parallel or serial configurations of current detection circuitry. Each such configuration may include multiple resistive devices of different resistive values.

Abstract: In an overcurrent protection circuit 23 according to the present invention, a timer circuit TMR that generates an overcurrent protection signal EN according to the results of comparison between a detection voltage Va (Vb) and VrefL and VrefH is configured as follows. When Va (Vb) has reached VrefL, the timer circuit TMR starts to count T1. When T1 has elapsed with Va (Vb) kept above VrefL, the timer circuit TMR changes EN to a disabled state and starts to count T2. When T2 has elapsed, the timer circuit TMR returns EN to an enabled state. On the other hand, after Va (Vb) has reached VrefL and T1 starts to be counted, when Va (Vb) has reached VrefH, the timer circuit TMR forcibly stops the counting of T1 without waiting for T1 to elapse, changes EN to a disabled state, and starts to count T2. With this configuration, it is possible to offer necessary and sufficient protection for an object to be protected (for example, a load or an element provided inside a device).

Abstract: A fault current limiter (FCL) includes a series of high permeability posts (1) for collectively define a core for the FCL. A DC coil (2), for the purposes of saturating a portion of the high permeability posts (1), surrounds the complete structure outside of an enclosure in the form of a vessel (3). The vessel (3) contains a dielectric insulation medium (4). AC coils (5), for transporting AC current, are wound on insulating formers (6) and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil (5) in the corresponding high permeability core are opposing. There are insulation barriers (7) between phases to improve dielectric withstand properties of the dielectric medium.

Abstract: A second forcing shutoff operation is performed for a power MOSFET 15 and the like, if a time when a load current (or a sense current Is) passing on a power supply line L exceeds a first threshold current Ia reaches a first reference time. On the other hand, the count value of a fuse time counter 71 is cleared to be “zero” so that the shutoff operation for the power MOSFET 15 and the like is not performed, if a normal state, in which neither an overcurrent nor a fuse current has occurred, continues for a second reference time without the first reference time being reached.

Abstract: This invention relates to a power supply circuit protecting method and a power supply circuit protecting apparatus. The apparatus is provided with a power supply circuit for converting a voltage from a three-phase alternating current inputting power supply into a predetermined voltage, and an output operation circuit for performing a predetermined operation by adopting an output voltage from the power supply circuit as input. In the apparatus, based on a current value on the input side or the output side of the power supply circuit, abnormality of the supply voltage is judged, and when there is an abnormality, the output operation circuit is controlled.

Abstract: A method for designing an ESD protected analog circuit is described. The method includes creating an analog circuit design comprising a plurality of interconnected functional components and circuit-level ESD protection components with predetermined electric properties for achieving a predetermined analog performance during normal operation of the circuit as well as a predetermined ESD robustness during an ESD event on the circuit. At least one ESD event is simulated on the analog circuit design to identify at least one weak spot in the circuit. Component-level ESD protection components are added into the analog circuit design around each identified weak spot to reduce failure of the weak spot during an ESD event.

Abstract: A current protection apparatus (200) and current protection method (1000) that may include programmable current protection characteristics has been disclosed. A current protection apparatus (200) may include a power distribution unit (230) with power distribution outlets (PDO-1 to PDO-8), each having a corresponding circuit breaker unit (CB1 to CB8). Each circuit breaker unit (CB1 to CB8) may operate in response to a processing unit (236) that can sample current values flowing between a respective power distribution outlet (PDO-1 to PDO-8) and a load device (LD1 to LD8). Processing unit 236 may operate under control of software stored on a memory (238) to control a switching circuit (320). Current protection characteristics for each circuit breaker unit may be independently programmed and/or altered by a user, for example by way of a computer (250).

Abstract: Disclosed herein is an apparatus for connection to the secondary terminals of a CT to prevent CT damage and electric shock when the secondary terminals are opened, by providing an input signal and operating a relay circuit to short the CT secondary terminals. The apparatus monitors opening of the CT secondary terminals, and to prevent accidental opening, determines opening and provides an over voltage breaking upon opening. To prevent false operation of the protecting relay connected to the secondary terminals caused by the over voltage generated by accident other than opening of the CT secondary terminals, a secondary delay time of operation of the protecting relay is provided that can be variously set by DIP switch or otherwise, allowing the user to choose a desired setting. Further, expected over voltage values can be set according to load characteristics, allowing the apparatus to operate during voltage above the set value.

Abstract: A current limiting device includes a constant current source circuit constructed and arranged to be connected to a direct current input voltage source and to regulate electrical current and a resonance source circuit receiving current from the constant current source circuit. The resonance source circuit is constructed and arranged to be electrically connected with an electro-luminescent (EL) lamp so that the EL lamp receives alternating current. The constant current source circuit and the resonance source circuit are constructed and arranged such that when current flows from the constant current source circuit to the resonance source circuit and to the EL lamp, a maximum peak current received by a user contacting an output of the device or contacting the EL lamp is less than about 0.7 mA.

Abstract: In a method and system for protecting a battery being charged by an electrical device, a current flowing through a cell stack of the battery is measured. If the measured current is greater than a predefined value the battery is isolated from the device. If subsequent current measurements made within a predefined time interval indicate that the measured current is less than or equal to the predefined value then the battery is recoupled to the device. If the measured current remains greater than the predefined value during the predefined time interval then a fuse is blown and the battery is disabled.

Abstract: The present disclosure provides a method and system for mounting a current transformer in proximity to a circuit breaker of an electrical system. Generally, a sensor assembly contains a plurality of current transformers (CTs) for measuring power wires from a main power supply. To accommodate measuring a greater number of wires than one sensor assembly can service, a plurality of sensor assemblies can be mounted end-to-end. The sensor assemblies can have symmetrical recessed portions that laterally align when mounted end-to-end by inverting one of the sensor assemblies. The lateral alignment allows CTs mounted lateral to the recessed portions to be aligned with corresponding circuit breakers, so that wires passing from the circuit breakers are aligned with the CTs, reducing bending stresses on the CTs in contrast to prior efforts. Changes in polarity caused by the inversion can be adjusted by software, firmware, hardware or a combination thereof.

Abstract: A ground fault detection system is provided where one current sensor is used to calibrate a second sensor in order to provide automatic zeroing of the difference measurement. The calibration is done gradually in order to differentiate between sensor drift and a transition in current due to a differential fault.

Abstract: An apparatus and a method of detecting arc faults that have reduced susceptibility to nuisance tripping. The apparatus includes a current sensor, a differential current input sense circuit, a differential current (di/dt) characteristics sense circuit, an absolute current input sense circuit, an absolute current characteristics sense circuit, a power supply, a tripping circuit, a processing unit, and an electromechanical interface. The di/dt characteristics sense circuit provides information relating to the characteristic di/dt signature of a power line current. The absolute current characteristics sense circuit provides information relating to the absolute current waveform characteristics of the power line current. The processing unit correlates the di/dt characteristics to the absolute current characteristics to distinguish between electrical arc faults and nuisance loads, thereby reducing the susceptibility of the apparatus to nuisance tripping.

Abstract: The voltage generator circuit includes a regulator, a first sensor circuit, and a second sensor circuit. The first sensor circuit includes a first transistor, a first resistor, and an error amplifier. When V1>Vth, the error amplifier senses an overcurrent condition to provide feedback to the operational amplifier to limit an output current. The second sensor circuit includes a second transistor, a second resistor, and a sensing transistor. When the output current exceeds a sense threshold current, the sensing transistor is turned ON to provide feedback to the operational amplifier 12 to limit the output current. The second sensor circuit has a higher setting of sense threshold current than does the first sensor circuit, while having a higher setting of sensing speed than does the first sensor circuit.

Abstract: In an overcurrent protection circuit for a switching power supply having multiple voltage supply sections, an overcurrent in a low voltage supply section is detected to make it possible to take a countermeasure against overload in a transformer winding, using a simple and low cost circuit design. The circuit comprises: a current detection resistor 33 to detect a current in secondary side of the transformer; transistors 53 and 52 to be turned on by the current detection; a photocoupler 50 to be turned on and off by the transistors; and a switching power supply controller 7 to control on-duty of a power MOSFET 6 for removing the overcurrent. The current detection resistor 33 is provided in the line of a secondary winding 30 so as to be able to individually limit a current flowing through the secondary winding 30.

Abstract: A surge current prevention circuit and DC power supply for preventing surge current in various operation applications with a small circuit configuration. A power switch connects an external power supply and a load. A first PMOS transistor is connected to a constant current supply. A second PMOS transistor, which forms a current mirror, is connected to a first and second NMOS transistor. A third PMOS transistor is connected to the first and second NMOS transistor, a third NMOS transistor, and fourth and fifth NMOS transistors. A control input is connected to the third NMOS transistor. The first NMOS transistor is connected to the fourth NMOS transistor. An external power supply is connected to the second NMOS transistor. The load is connected to the fourth NMOS transistor.

Abstract: A surge suppression device includes a first and second coil positioned in close proximity to one another such that the windings of each coil are disposed at an angle thereto. In a preferred embodiment, the coils are disposed such that the windings of each coil are placed at a right angle (90 degrees) to one another. However, angles of varying degree can be employed. Varying configurations of the coil winding placement include a “sandwiched” type configuration, a “one on the top of the other” configuration as well as an intertwined configuration. Each embodiment employs additional surge elements such as metal oxide varistors (MOVs). It is unnecessary to employ any ferrous material core for any of the coils used in the novel device of the present invention.

Abstract: An electronic fuse comprising an integrated circuit having a control output terminal coupled to a control electrode of a power semiconductor switching device, the power semiconductor switching device being coupled in series with a load between first and second potentials, the integrated circuit further comprising a current sense input for sensing the current through the power semiconductor switching device, the integrated circuit further comprising a driver circuit for driving the power semi-conductor switching device, the driver circuit being coupled to a current limiting circuit responsive to the sensed current in the power semiconductor switching device, the current limiting circuit controlling the driver circuit whereby if the current through the power semiconductor switching device exceeds a predetermined threshold, the current limiting circuit generates a command to pulse the power semiconductor switching device on and off in a period of pulsed operation to maintain the current in the power semiconducto

Abstract: A surge suppression device includes a first and second coil positioned in close proximity to one another such that the windings of each coil are disposed at an angle thereto. In a preferred embodiment, the coils are disposed such that the windings of each coil are placed at a right angle (90 degrees) to one another. However, angles of varying degree can be employed. Varying configurations of the coil winding placement include a “sandwiched” type configuration, a “one on the top of the other” configuration as well as an intertwined configuration. Each embodiment employs additional surge elements such as metal oxide varistors (MOVs). It is unnecessary to employ any ferrous material core for any of the coils used in the novel device of the present invention.

Abstract: An overcurrent protection circuit of a switching power supply apparatus, wherein a rectangular wave voltage is formed from an input voltage by the ON/OFF operation switching means, and an output voltage is formed by smoothing the rectangular wave voltage by using an inductance device and a capacitor, restricts overcurrent by detecting the peak current of a current flowing through the switching means and by using an input voltage Vin, an output voltage Vout and a voltage proportional to the ON/OFF ratio D of the switching means.

Abstract: An overcurrent/leakage protection circuit installed in an electric socket or the like for over current/electric leakage protection, which includes a relay, a SCR (silicon controlled rectifier) which controls the relay, a trigger circuit which triggers the SCR, a constant current detector, and a micro current detection amplifier, wherein the relay has a common contact connected to a first power line, a normal close contact for power output of the first power line, and a normal open contact bridged to a second power line through an alarm lamp; the trigger circuit is driven to trigger the SCR upon detection of an overcurrent or short-circuit detected by the constant current detector or an electric leakage by the micro current detection amplifier, causing the normal close contact to be opened to cut off power supply from the load.

Abstract: A fault detector sensor includes a current transformer, with two multi-turn windings each formed around a portion of the core, with one winding adjacent to each of the hot and neutral wires of the power line being protected. Both windings are connected in series in a way which reinforces arc fault noise generated by arc faults involving the line and neutral, but which causes signal reduction for noise signals from the line and neutral, or either, to ground. The windings and core are selected to self resonate at a frequency that excludes power line carrier frequencies but which includes arc fault frequencies. The core optionally has a third winding, forming a grounded neutral transformer, or ground fault detector. Instead of a third winding, one of the arc fault sensing windings can act as a dual function sensor.

Abstract: An overcurrent protection circuit of a switching power supply apparatus, wherein a rectangular wave voltage is formed from an input voltage by the ON/OFF operation switching means, and an output voltage is formed by smoothing the rectangular wave voltage by using an inductance device and a capacitor, restricts overcurrent by detecting the peak current of a current flowing through the switching means and by using an input voltage Vin, an output voltage Vout and a voltage proportional to the ON/OFF ratio D of the switching means.

Abstract: A switch gear protection circuit for use in electric vehicles provides parallel circuit pathways for selectively coupling a power source to a capacitive load. A first pathway includes a main switch element that preferably is a high-current contactor or a high-current, low-voltage relay switch. A second pathway, which is in parallel with the first pathway, includes a low-voltage, low-current switch element in series with a circuit breaker element such as a fuse. When it is desirable to open the main switch element in the first pathway, the second pathway is closed. Once the second pathway is closed, the voltage drop across the first pathway is reduced and the first switch element can be opened. The parallel arrangement provides the ability to use low-voltage switch elements, that are relatively inexpensive compared to high-voltage components.