Abstract: Method for detecting an electric arc in a photovoltaic installation, which includes measurement (E6) of voltage values at at least one site of the electrical circuit of the photovoltaic installation; digitization (E8) of the measured voltage values so as to form voltage data; formation (E11) of a window of n recent digitized voltage data; computation (E12) of a test value associated with the said window of the n voltage data; analysis (E13) of a test vector comprising m test values associated with m recent windows generating a quantity arising from this analysis representative of a risk of electric arc; comparison (E15) of this quantity arising with at least one threshold so as to deduce therefrom the presence or otherwise of an electric arc within the photovoltaic installation.

Abstract: A motor control circuit comprising a speed control circuit configured to output speed command information relating to the rotational speed of a motor based on target information relating to a target rotational speed and rotational speed detection information of the rotational speed of the motor, a drive stop control circuit configured to output a first drive stop control signal for performing braking control of the motor or a second drive stop control signal for performing free-run stop control of the motor based on the rotational speed detection information and the speed command information when input of the target information is stopped, and a drive signal generation circuit configured to generate a drive control signal for driving the motor based on the first drive stop control signal or the second drive stop control signal when the first drive stop control signal or the second drive stop control signal is output.

Abstract: A relay system is provided which is designed to avoid flow of inrush current through a capacitor in a pre-charge mode wherein the capacitor is pre-charged. The relay system includes a pair of power lines, a capacitor, a series-connected assembly, a control circuit, and a relay module. The relay module includes two main switches, a main coil, and a sub-coil. In the pre-charge mode, the control circuit energizes both the main and sub-coils to turn on only one of the main switches. Before entering the pre-charge mode, the control circuit diagnoses the sub-coil. When the sub-coil is determined as being malfunctioning, the control circuit inhibits the pre-charge mode from being entered.

Abstract: According to one aspect, embodiments herein provide a power distribution device including a power outlet comprising a receptacle including an internal conductor configured to be coupled to a power source and to an external conductor inserted into the receptacle, a switch configured to provide an indication of whether the external conductor has been sufficiently inserted within the receptacle, a relay configured to form a first connection between the external conductor and the power source, a transistor configured to be coupled in parallel with the relay, to form a second connection between the external conductor and the power source, and a controller configured to determine, based on the switch, that the external conductor is being removed, in response to the external conductor being removed, control the relay to sever the first connection, and in response to opening the relay, control the transistor to sever the second connection after a predetermined delay.

Abstract: A multi-channel power controller includes a main controller communicatively coupled to a plurality of standard power control circuit boards. Each of the standard power controller circuit boards includes a nexus having a plurality of virtual channels and a plurality of solid state power controllers. Each of the solid state power controllers is controlled by one of the virtual channels. A plurality of physical control channels operable to control power to at least one load. Each physical control channel of the plurality of physical control channels is controlled by a corresponding solid state power controller of the plurality of solid state power controllers. At least one of the virtual channels controls more than one of the physical control channels in the plurality of physical control channels.

Abstract: A device for connecting to a power network includes a circuit board, a first input-side connection point, to which a first phase of the power network can be connected, a second input-side connection point, to which a second phase of the power network can be connected, and a first and second electrical conductor. The first conductor is connected to the first input-side connection point and the second conductor is connected to the second input-side connection point inside the device. The first conductor is routed as a conductor trace in an interior layer of the circuit board and includes a constriction. The second conductor is routed past the constriction such that electrical insulation existing between the constriction of the first conductor and the second conductor is destroyed in the case of a short-circuit current, to provide an electrically conductive connection between the first and second conductor exists.

Abstract: A power system includes a DC power source having a maximum output voltage, a DC/AC inverter having an input coupled via a connection to the DC power source and an output for supplying AC power to a load, and a control circuit for controlling the DC/AC inverter. The control circuit is configured to maintain a DC voltage at the input of the DC/AC inverter above a threshold voltage to inhibit arcing as a result of a break in the connection between the DC power source and the DC/AC inverter. The threshold voltage is substantially equal to the maximum output voltage of the DC power source less a minimum arcing voltage for the connection between the DC power source and the DC/AC inverter.

Abstract: Method and system for controlling and limiting the damage caused by arcs formed on exposed conductors in electrical distribution equipment involve using the tendency of an arc to move in a direction away from a current source and toward the terminal ends of the conductors. An arc interruption device, or arc interrupter, is placed over the terminal ends of the conductor to capture the arc as it travels toward the terminal ends of the conductors. Within the arc interrupter, the shape of the arc is conformed to geometries designed to stretch and extend the arc to the point where it can no longer be sustained and is extinguished.

Abstract: A two terminal arc suppressor for protecting switch, relay or contactor contacts and the like comprises a two terminal module adapted to be attached in parallel with the contacts to be protected and including a circuit for deriving an operating voltage upon the transitioning of the switch, relay or contactor contacts from a closed to an open disposition, the power being rectified and the resulting DC signal used to trigger a power triac switch via an optoisolator circuit whereby arc suppression pulses are generated for short predetermined intervals only at a transition of the mechanical switch, relay or contactor contacts from an closed to an open transition and, again, at an open to a close transition during contact bounce conditions.

Abstract: An apparatus and a method for detecting phase deficiency in an inverter is provided, the method including deciding whether a sector of the output current is a sector where current detection is possible based on switching operation status of the switching element in the inverter, maintaining a phase deficiency variable when deciding the current detection in the sector of the output current to be impossible, adding a count to a phase deficiency variable to accumulate when deciding the current detection in the sector of the output current to be possible and deciding the output current to be within a phase deficiency band, and determining as phase deficiency when the phase deficiency variable is greater than a prescribed detection level.

Abstract: Distributed electronic protections and control architecture enabling simultaneous fault clearance without conflicting fault isolation logic. A plurality of modular equipment centers (MECs) is spatially distributed throughout a vehicle to service equipment loads with power and data. In one embodiment, protective functions are embedded on integrated protection chipsets (IPCs) within the distributed architecture of the vehicle. The IPCs implement a plurality of protective functions where coordinated or independent fault assessments are performed.

Abstract: A direct-current circuit breaker includes a switching unit inserted in the direct-current line; and a commutation circuit that includes a series circuit including a first current-limiting element and an interrupting unit that forms a current zero point by superimposing a resonance current on a direct current flowing in the direct-current line and interrupts the direct current at the current zero point, that is connected in parallel with the switching unit, and that becomes a flow path for the direct current after the switching unit is opened, wherein current interruption is performed by the interrupting unit after the switching unit is opened.

Abstract: A method for adaptive load control by an electronic device is described. The method includes determining a wiring mode. The method also includes determining a frequency of a power source. The method further includes capturing a voltage waveform. The method additionally includes capturing a current waveform. The method also includes determining a load type of a load based on the voltage waveform and the current waveform. The method further includes determining a power factor based on the voltage waveform, the current waveform and the wiring mode. The method additionally includes operating the load based on the load type, the power factor and the frequency.

Abstract: A two terminal arc suppressor for protecting switch, relay or contactor contacts and the like comprises a two terminal module adapted to be attached in parallel with the contacts to be protected and including a circuit for deriving an operating voltage upon the transitioning of the switch, relay or contactor contacts from a closed to an open disposition, the power being rectified and the resulting DC signal used to trigger a power triac switch via an optoisolator circuit whereby arc suppression pulses are generated for short predetermined intervals only at a transition of the mechanical switch, relay or contactor contacts from an closed to an open transition and, again, at an open to a close transition during contact bounce conditions.

Abstract: An electric arc eliminating apparatus includes a power supply circuit, a voltage dividing circuit, a contacting unit, a triggering unit, a voltage control switch, an interface and a connector. When the connector is inserted into the interface but not completely connected with the interface, the contacting unit is in an open state, the power supply circuit cannot output electrical power to the connector via the interface. When the connector is inserted into and completely connected with the interface, the contacting unit is in a closed state, a voltage of the power supply circuit is divided by the voltage dividing circuit, the voltage control switch is turned on, the power supply circuit provides electrical power to the connector via the interface.

Abstract: A circuit protection device includes a plasma gun configured to emit an ablative plasma along an axis, and a plurality of electrodes, wherein each electrode is electrically coupled to a respective conductor of a circuit and is arranged substantially along a plane that is substantially perpendicular to the axis such that each electrode is positioned substantially equidistant from the axis.

Abstract: According to one embodiment, there is provided a protection relay apparatus that protects lines of a three-phase alternating current power system, the protection relay apparatus including a fault detector to detect a fault of the line, an opening unit to open a circuit breaker of a fault phase in which the fault has occurred through detection of the fault, a fault phase voltage measurement unit to measure a voltage of the fault phase after the circuit breaker is opened, a fault recovery determination unit to determine whether the fault is recovered or not based on the voltage, and a closing unit to close the circuit breaker when the fault recovery determination unit determines that the fault is recovered.

Abstract: A battery management system for a battery module having at least one battery cell provides a current path between poles of the battery module in response to a tripping signal. The current path prevents or terminates an arc in a fuse of the at least one battery cell after the fuse has been tripped. The battery management system can further include an apparatus to trip the fuse and provide the tripping signal in response to identifying the tripping of the at least one fuse. The battery management system can further include an apparatus to receive the tripping signal.

Abstract: A high voltage DC breaker apparatus configured to interrupt a fault current occurring in a high voltage DC conductor comprises a mechanical interrupter, at least one semiconductor device connected in series with the interrupter, an arrester connected in parallel with the semiconductor device and an LC-circuit connected in parallel with the series connection of the semiconductor device and the interrupter. A control unit is configured to, upon detection of a fault current, control switching of the semiconductor device at a frequency adapted to the values of an inductance and a capacitance of the LC-circuit for charging the capacitance by the fault current while making the current through the interrupter oscillating with an increasing amplitude and the interrupter to open for having the mechanical contacts thereof separated when current zero-crossing is reached for obtaining interruption of the fault current through the interrupter.

Abstract: Equipment protection systems, arc containment devices, and methods of assembling arc containment devices are disclosed. In one example, an electrical isolation structure includes a conductor base, a cover coupled to the conductor base and defining an isolation chamber, a containment shield disposed on the conductor base within the isolation chamber, and a biasing assembly positioned between the cover and the containment shield. The containment shield defines a containment chamber configured to enclose the plurality of electrode assemblies. The containment shield is configured to at least partially contain the arc products within the containment chamber. The biasing assembly is configured to permit the containment shield to move away from the conductor base to thereby define a gap between the conductor base and the containment shield to enable at least some of the arc gases to vent from the containment chamber.

Abstract: A circuit protection device is provided for use with a circuit that includes at least one pair of conductors. The protection device is configured to generate an arc. The protection device includes at least a pair of electrode assemblies electrically coupled to the at least one pair of conductors and a conductor base to support the pair of electrode assemblies. The protection device includes a cover coupled to the conductor base and defining at least one isolation chamber, wherein the electrode assemblies are disposed within the isolation chamber. The protection device includes a containment shield moveably coupled to the cover. The containment shield defines a containment chamber configured to contain charged particles produced by the arc. The containment shield is operative to move relative to the cover in response to a change in pressure produced by the arc within the containment chamber.

Abstract: A two-pole circuit breaker is provided that includes a first mechanical pole, a second mechanical pole and an electronic pole. The first mechanical pole includes a first armature having a first armature extension, and the second mechanical pole includes a second armature having a second armature extension. The electronic pole includes a first solenoid and a second solenoid, the first armature extension is disposed adjacent the first solenoid, and the second armature is disposed adjacent the second solenoid. Numerous other aspects are provided.

Abstract: A device for detecting a fault in an AC supply comprises a circuit (CT, 100) for detecting a particular type of fault in an AC supply to a load (LD) and providing a corresponding output (10). A relay (RLA) is responsive to said output (10) to open a set of load contacts (SW1) in the AC supply to disconnect the load from the supply. Test means (TS, Rt, W2) are provided for simulating a supply fault of the said type, and means (C3, R5, SCR2, SOL, SW2) are provided for causing the load contacts (SW1) to open if they do not open in response to the simulated fault within a certain period of time.

Abstract: A circuit arrangement includes a semiconductor switch having a control terminal and a load path. A drive circuit is coupled to the control terminal of the semiconductor switch. The drive circuit has a current measuring arrangement for determining a load current flowing through the load path and is designed to prevent the semiconductor switch from being driven in the off state if the load current exceeds a predetermined load current threshold value. A fuse is coupled in series with the load path of the semiconductor switch triggers if a triggering condition dependent at least on the load current is present.

Abstract: A DC circuit breaker including a pair of arcing contact members for holding an arc, an interaction element, adapted for interacting with the arc in dependence of whether the arc is in a first or second state such that the arc voltage drop in the first state is lower than the drop in the second state, a resonance branch coupled in parallel to the contact members thereby forming a resonance circuit adapted for letting a resonance branch current Ir oscillate thereby inducing oscillations of an arc current Ia, wherein the resonance branch includes a coupling element for coupling the resonance branch with the arc, such that the arc is brought to the first state when the current Ir in the resonance branch has a first direction, and that the arc is brought to the second state when the current Ir in the resonance branch has a second direction.

Abstract: A power supply apparatus for a vehicle is provided which supplies electric power to a power supply unit and charges electric power from the power supply unit via a power port. The vehicle includes a plurality of power inverter circuits which are connected to a common storage unit in parallel. The plurality of power inverter circuits include an electric power transferring power inverter circuit connected to the power port via an electric power transferring electric path, and are divided into a first category including the electric power transferring power inverter circuit and a second category. The power supply apparatus includes a connection prohibiting unit which realizes a state in which the power inverter circuit included in the first category is electrically connected to the storage unit, and the power inverter circuit included in the second category is disconnected from the storage unit.

Abstract: In a switchgear cabinet, the line side power conductors upstream of the main breaker are surrounded with are attenuating/extinguishing channels and protective conduit in a location prior to the conductor's attachment to the main breaker. Thus, passive arc attenuation can be had prior to the breakers, Personal Protection Equipment (PPE) levels can be predicted and controlled, and the need for action by circuit breakers during an arcing event is substantially lessened.

Abstract: An electrical fault mitigation system includes a mitigation device including a containment chamber defining a cavity, a first electrode positioned within the cavity and coupled to a first conductor, and a second electrode positioned within the cavity and coupled to a second conductor. The mitigation device also includes a first voltage source, and a plasma gun positioned within the cavity and configured to emit ablative plasma using the first voltage source to discharge energy from an electrical fault. The system also includes a first voltage limiter device configured to limit a voltage of the first conductor from increasing above a predetermined threshold to prevent a second voltage source from generating a second electrical arc between the first electrode and the second electrode when the second voltage source applies a voltage across the first electrode and the second electrode.

Abstract: A current controlling circuit comprises a DC power source, an inductor, a N-channel Metal Oxide Semiconductor (NMOS), one or more LEDs connected in series, a first resistor and a switching arrangement. The positive terminal of the DC power source is connected to the inductor in series. The series of LED is connected in series with the inductor and the first resistor. According to an embodiment the switching arrangement comprises a second resistor, a first switch and a second switch. The second resistor is connected in series with the second switch and connected in parallel with the first switch. The switching arrangement is connected in series with the first resistor and the negative terminal of the DC supply.

Abstract: In a first aspect, a ground fault circuit interrupt (“GFCI”) device is provided for use with an AC power system that includes a line conductor, a neutral conductor and a transformer. The line conductor and the neutral conductor are each coupled between a source and a load, and the neutral conductor is coupled to ground at the source. The transformer includes a first primary winding coupled in series with the line conductor, a second primary winding coupled in series with the neutral conductor, and a secondary winding. The device includes a grounded neutral fault detector circuit coupled to the secondary winding. The grounded neutral fault detector circuit: (a) drives the secondary winding with a multi-frequency AC signal, (b) monitors a multi-frequency load signal in the secondary winding, and (c) provides a first detection signal if the monitored load signal exceeds a predetermined threshold. Numerous other aspects are also provided.

Abstract: The present technique, applicable to low voltage, medium voltage, and high voltage MCCs and other power management systems, provides for substantially containing and directing an arcing fault and resultant ionized gases within a stab enclosure or housing disposed in the MCC. For example, the stab housing may have reduced stab-openings at the power bus interface to diminish the potential of an arc flash (and ionized gases) from reaching the power buses. Furthermore, phase-to-phase isolation barriers may be employed within the stab housing to reduce the potential of an arcing fault going phase-to-phase. Moreover, to reduce arc flash damage within the MCC, the walls and barriers, including walls around the stabs, within the housing may be configured to direct the arc on a preferred path to a desired location within the housing to extinguish the arc in less than 0.1 second or 6 cycles, or even less than 0.033 second or 2 cycles.

Abstract: A power supply device for plasma processing, wherein electric arcs may occur, comprises a power supply circuit for generating a voltage across output terminals, and a first switch connected between the power supply circuit and one of the output terminals. According to a first aspect the power supply device comprises a recovery energy circuit connected to the output terminals and to the power supply circuit. According to a second aspect the power supply device comprises an inductance circuit including an inductor and a second switch connected parallel to the inductor. According to a third aspect the power supply device comprises a controller for causing the power supply circuit and the first switch to be switched on and off. The controller is configured to determine a quenching time interval by means of a self-adaptive process. The quenching time interval defines the time interval during which, in an event of an arc, no voltage is generated across the output terminals.

Abstract: A voltage measurement is made between two points in a circuit. If the measured voltage exceeds a predetermined amount, a switch is operated to electrically connect the two points.

Abstract: A circuit protection system has a normal mode, and a maintenance mode with reduced potential arc flash energy. A downstream circuit breaker is mounted within a first enclosure comprising a first access panel. A locking mechanism locks the first access panel closed. An upstream breaker is mounted within a second enclosure comprising a second access panel. A current sensor senses current and is in communication with an electronic trip unit that controls current interruptions by the upstream breaker based on a trip setting. A user interface device is accessible when second enclosure is closed, and allows user selections of normal and maintenance modes. When maintenance mode is selected, the trip unit changes the trip setting such that potential arc flash energy is reduced. The system is configured to keep the first access panel locked closed based on normal mode being selected, and allow unlocking based on maintenance mode being selected.

Abstract: In a method for adapting an arc sensor (35) to a position in an electrical installation system, according to the invention a specifiable number of specifiable arcs are simulated and/or produced at least at a first position in the installation system, wherein after each simulated or produced arc, at least one current curve and/or voltage curve is recorded in a measured-value recording unit (2), wherein at least one characteristic of the recorded current curves and/or voltage curves is determined and stored, and the arc sensor (35) is trained for the electrical installation system.

Abstract: A system and associated components for providing an intelligent circuit breaker being adapted to communicate with, monitor and control various devices within a commercial or residential premises. In one embodiment, the system is adapted for low cost, ease of installation and operation, and ease of manufacture. The intelligent circuit breaker may also be adapted to send data relating to sensed parameter or conditions to, and receive commands from, a user interface. Methods for operating such breakers and converting existing circuit breakers to intelligent circuit breakers consistent with the aforementioned system and components are also described.

Abstract: A solenoid operated circuit comprises a solenoid switch having a solenoid coil for moving one or more electrical contacts from a first position to a second position to switch an electrical motor ON/OFF, and a solenoid controller that includes an arc suppression circuit that mitigates a reverse self-induced voltage from the electrical motor thereby suppressing electrical arcing on switch contacts.

Abstract: A plasma gun with two gap electrodes on opposite ends of a chamber of ablative material such as an ablative polymer. The gun ejects an ablative plasma at supersonic speed. A divergent nozzle spreads the plasma jet to fill a gap between electrodes of a main arc device, such as an arc crowbar or a high voltage power switch. The plasma triggers the main arc device by lowering the impedance of the main arc gap via the ablative plasma to provide a conductive path between the main electrodes. This provides faster triggering and requires less trigger energy than previous arc triggers. It also provides a more conductive initial main arc than previously possible. The initial properties of the main arc are controllable by the plasma properties, which are in turn controllable by design parameters of the ablative plasma gun.

Abstract: A circuit for interfacing to a limit switch configured to be closed when a wire connected to the limit switch is relatively hot and configured to be opened when the wire is relatively cold includes an input, an output, and a control portion. The input is configured to receive a pulse width modulated (PWM) signal having a duty cycle with a high pulse and a low pulse. The output is configured to apply the PWM signal to an external transistor associated with the wire, and a control portion. The high pulse actuates heating of the wire when the high pulse is applied to the external transistor. The control portion is configured to cause voltage across the limit switch to be substantially zero, whereby arcing of the limit switch is relatively minimal, when the limit switch closes while the high pulse is being applied to the external transistor.

Abstract: The reclosing control device configured to perform a reclosing control in case of a fault in a transmission line. Further, the reclosing control device includes a voltage detection unit configured to detect a faulted phase voltage waveform and extract a harmonic component contained in the faulted phase voltage waveform; a HR calculating unit configured to calculate ratio values between even harmonics and odd harmonics based on the extracted harmonic component; and a reclosing control unit configured to determine whether or not an arc is finally extinguished based on the calculated ratio value and perform a reclosing control depending on a result of the determination.

Abstract: The invention is a photovoltaic-specific, DC load-break disconnect switch intended for applications where load-break capability is only required under abnormal operating conditions or in an emergency due to the catastrophic failure or other system components. Under normal operating conditions, the load will be switched off before a DC disconnect switch is opened. Under conditions where a load-break disconnect operation is required, an alternate path is automatically provided through a sacrificial fuse to divert current from opening contacts such that the fuse interrupts the current and not the contacts, thereby providing a substantially arcless load break. The current rating of the sacrificial fuse may be orders of magnitude less than the normal carry current. Equipment based on this invention will provide a one-time load break function that is renewable by the replacement of a fuse. The invention leverages the superior, cost-effective fault clearing capability of fuses in DC applications.

Abstract: A switchgear assembly includes a vacuum interrupt chamber and a short-circuiting system arranged in the vacuum interrupt chamber. To enable rapid switching with physically simple means, a vacuum area of the vacuum interrupt chamber in which a fixed contact piece is placed is subdivided via a membrane, which is provided with a breaking line and which can be penetrated by a moving piston system to the contact piece during switching. The switchgear assembly can be utilized in a low-voltage, medium-voltage or high-voltage assembly.

Abstract: An electrical switching device is presented. The electrical switching device includes multiple switch sets coupled in series. Each of the switch sets includes multiple switches coupled in parallel. A control circuit is coupled to the multiple switch sets and configured to control opening and closing of the switches. One or more intermediate diodes are coupled between the control circuit and each point between a respective pair of switch sets.

Abstract: A monitoring system for and method of preventing electrical arcs in a solar energy system is disclosed. The monitoring system includes an insulation resistance (IR) monitoring device, a disconnect switch, a power supply, an indicator, and optionally a communications interface. A method of preventing electrical arcs in a solar energy system using the monitoring system may include, but is not limited to, the steps of providing and installing the monitoring system in a solar energy system; activating the solar energy system and the monitoring system; continuously monitoring the insulation resistance of a conductor; if the lower and/or upper resistance threshold of the IR monitoring device is not satisfied, then transmitting a shutdown signal to the disconnect switch, thereby turning off the power to the affected circuit, and indicating the presence of the potential fault condition.

Abstract: The present invention discloses an arc extinguishing switch, including a mechanical switch and a first electric branch connected in parallel with a first contact branch of the mechanical switch, the first electric branch includes a first controllable unidirectional turn-on subbranch and a second controllable unidirectional turn-on subbranch, the first controllable unidirectional turn-on subbranch and the second controllable unidirectional turn-on subbranch are respectively controlled by two thyristors to be turned on in AC positive and negative periods correspondingly and share a first capacitor connected in series with the two thyristors. The invention further discloses a switching method using the arc extinguishing switch. In the invention, the high power requirement for the thyristor in the arc extinguishing switch and the product cost are lowered, and it is avoided that the mechanical switch is bypassed when the short-circuit failure occurs on the thyristor.

Abstract: In an electrical distribution system an arc management system has a transducer mounted in proximity to the circuit breaker for detecting and signaling a secondary effect of an overcurrent event within the case of the circuit breaker. The transducer provides an additional input to an arc fault detection system using other detectors and thus helps to control nuisance activations of the arc extinguishing mechanism. The system is particularly suited for circuit breakers without electronics, or the like, allowing for retrofit of existing systems. The system may monitor and act upon the excessive duration of the secondary effects.

Abstract: An electrical circuit for protecting an electrical load from overload current is provided. The system includes a voltage transformer configured to receive AC mains voltage from an electric mains supply and further configured to apply reduced voltage to the electrical load. A control switch comprising metal contacts is connected to the voltage transformer. The control switch is configured to facilitate application of reduced value of AC mains voltage to the electrical load. A reduced value of current flowing through the electrical load is measured by a current transformer connected in series with the electrical load. The reduced value of current is then used for estimating a current consumption value in event of AC mains voltage being directly applied to the electrical load. A control signal is then used for disconnecting the electrical circuit if the estimated current consumption value is greater than threshold overload current value.

Abstract: A hybrid DC contactor includes contacts that provide a first current path between a DC power source and a load, an electromagnetic coil to position the contacts, a semiconductor switch in parallel with contacts that, when turned on, provides a second parallel current path that diverts current away from the contacts when the main contacts are being opened in either direction. A controller is provided to terminate power to the electromagnetic coil to open the contacts, detect an arc voltage across the contacts as the contacts open, provide a gate signal to the semiconductor switch to pulse the switch on for a pre-determined period of time to route current to the semiconductor switch, measure a current through the contacts and, if current is present through the contacts, then provide another gate signal to the semiconductor switch to pulse the switch on again so as to route current thereto.

Abstract: A two terminal arc suppressor for protecting switch, relay or contactor contacts and the like comprises a two terminal module adapted to be attached in parallel with the contacts to be protected and including a circuit for deriving an operating voltage upon the transitioning of the switch, relay or contactor contacts from a closed to an open disposition, the power being rectified and the resulting DC signal used to trigger a power triac switch via an optoisolator circuit whereby arc suppression pulses are generated for short predetermined intervals only at a transition of the mechanical switch, relay or contactor contacts from an closed to an open transition and, again, at an open to a close transition during contact bounce conditions.

Abstract: The method of detecting an arc fault in a power circuit includes determining a first signal related to current flowing in the power circuit is determined and analyzing the first signal to determine whether the signal indicates the presence of an electric arc in the power circuit. In case the first signal indicates the presence of an electric arc in the power circuit, means for suppressing an electric arc are activated. A second signal related to current flowing in the power circuit is then determined and analyzed. An occurrence of an arc fault in the power circuit is signaled if the second signal does not indicate the presence of an electric arc. The system for detecting an arc fault is designed to perform a corresponding method.