Abstract: A safety switching apparatus for safe disconnection of a load in an automated installation has at least one input for receiving an analog input signal. It further has an A/D converter which converts the analog input signal to a digital signal. An evaluation and control unit controls at least one output switching element as a function of the digital signal. An analog signal combiner is designed to superimpose an analog test signal on the analog input signal in order to form an analog combination signal. The analog combination signal is supplied to the A/D converter. The operation of the safety switching apparatus can then be monitored for faults by means of the analog test signal.

Abstract: An electrical distribution system is provided for selectively connecting an electrical power source to load devices comprising a panelboard having a plurality of load circuit positions. A remote operated device is mountable in the panelboard comprising a load control device, and a device control for controlling the load control device. The device control comprises a programmed controller for operating the load control device responsive to control commands and a communication circuit for receiving control commands. An input/output (I/O) controller is mounted in the panelboard for controlling operation of the remote operated device, the I/O controller comprising a programmed controller for generating the control commands for commanding operation of the remote operated device, the control system including a communication circuit for communication with the remote operated device communication circuit.

Abstract: An LED package having an MEMS switch operated by electrostatic force, capable of continuously protecting an LED from excessive current due to electrostatic discharge. The LED package includes a submount with first and second electrode patterns formed thereon; an LED mounted on the submount, having an n-electrode electrically connected to the first electrode pattern and a p-electrode electrically connected to the second electrode pattern; and an MEMS switch including a first conductive plate and a second conductive plate bent to have an area over and vertically apart from the first conductive plate, wherein the first and second conductive plates are electrically connected to the first and second electrode patterns, and the second conductive plate comes in contact with the first conductive plate by electrostatic force upon being applied with voltage higher than a predetermined level of voltage.

Abstract: An arc fault detection circuit collects samples of sensed current, determines a peak current value from the samples for each line cycle, determines a hysteresis value for a compressor load as a function of differences between the peak current values, and generates a trip signal responsive to the sensed current and the hysteresis value. The circuit determines a difference value for each line cycle from the present peak current value less the previous peak current value, low pass filters the difference value to provide a low pass filtered value, determines a peak value from the low pass filtered value, determines that the absolute value of the low pass filtered value is less than a portion of the peak value and responsively saves the peak value, and determines the hysteresis value as a function of the saved peak value. An operating mechanism opens separable contacts responsive to the trip signal.

Abstract: The present invention is a simple, inexpensive and reliable device for monitoring and alerting of a power disruption to an appliance or a piece of equipment. An audible and/or visual alarm may be generated in the event that a specific or a piece of electrical equipment becomes disconnected from its electrical source. The device for monitoring and alerting of a power disruption may operate from an internal battery in case the electrical power source to the appliance disrupted. Additionally, a power-surge-suppression, a rechargeable battery, and a charger for the battery may make the device more reliable. The remote receiver may receive a broadcasted alarm signal from the monitoring device and then notify a user with a visual and/or audible alarm at a location where the alarm is more likely to be seen and heard.

Abstract: An electric coupling device includes a housing having a front socket opening and a rear chamber formed by two side wall. Two prongs are disposed in the socket opening of the housing and each has a free end extended out of the housing, and two conductor terminals are electrically coupled to the prongs, and a circuit breaker is coupled between one of the prongs and one of the conductor terminals and includes a conductor blade made of memorized material for selectively terminating or switching off the electric circuit between the conductor terminal and the prong when overheated or overloaded, and a reset knob may selectively and easily and readily switch on the electric circuit again.

Abstract: A solid-state direct replacement relay assembly, and a method for installing and using it to replace the mechanical-style relays in the electrical cabinets of a locomotive. Solid-state relay components are substituted to upgrade locomotive relay systems, and to improve train controls. Normally solid-state relays cannot directly handle standard locomotive voltages without an external power supply that requires modification to the original train design and wiring. The solid-state relay assembly is coupled to a D.C./D.C. converter, which steps 75 volts down to approximately 5–32 volts, and is used to control the solid-state relay assembly. The use of the solid-state relay assembly device requires no modification to the existing electrical wiring system of any new or old locomotive.

Abstract: There is provided an apparatus for producing a trip signal to activate a circuit breaker in an alternating current power line, said apparatus comprising: a sensing circuit operable to sense values representing: a phase difference between current and voltage in said power line; and current amplitude in said power line; a comparison circuit operable to compare said sensed values of phase difference and current amplitude with a trip characteristic defining fault conditions and non-fault conditions and to generate a fault indication signal when a fault condition arises; a fault discriminator operable in response to said fault indication signal to generate a fault-identifying signal discriminating between: a first class of fault in which a mean current value after said fault indication increases relative to a mean current value before said fault indication; and a second class of fault in which a mean current value after said fault indication does not increase relative to a mean current value before said fault indi

Abstract: An electromagnetic circuit breaker assembly, comprising at least one circuit breaker, is provided with a reverse polarity circuit that reduces the voltage presented to the terminals of the circuit breaker to which it is electrically connected when the terminals are further connected to a source of voltage in reverse polarity. The circuit breaker assembly is tripped due to the reverse polarity set-up, and remains tripped until the polarity is corrected. The electromagnetic coil is continuous provided with sufficient voltage so that the breaker may not be manually reset until the polarity is corrected. Preferably, the breaker is mechanically connected with another circuit breaker to create an assembly that will protect circuitry and devices against both a reverse polarity condition and an overload condition under normal operation. To this end, the reverse polarity circuit does not affect operation of the circuit breaker assembly if the polarity is in accordance with the normal set-up.

Abstract: The present invention is directed to an electrical wiring protection device including a housing assembly including at least one receptacle, the at least one receptacle being configured to receive plug contact blades inserted therein. The housing assembly includes a hot line terminal, a neutral line terminal, a hot load terminal, a neutral load terminal, a hot user-accessible receptacle contact, and a neutral user accessible receptacle contact. A fault detection circuit is coupled to the hot line terminal and the neutral line terminal. The fault detection circuit is configured to detect at least one fault condition and provide a fault detect signal in response thereto. An interrupting contact assembly is coupled to the fault detection circuit. A weld breaker mechanism is coupled to the interrupting contact assembly. The weld breaker mechanism is configured to strike the first pair of contacts and/or the second pair of contacts in response to the tripping stimulus.

Abstract: Apparatus and method for controlling movement of an object through a medium using a magnetic field by combining the magnetic field of a primary electromagnetic coil having a central axis with the magnetic fields of a plurality of secondary electromagnetic coils having axes generally parallel to the central axis of the primary coil and positioned within the primary coil to produce an operational magnetic field by which movement of the object in a medium is controlled outside of the primary coil.

Abstract: According to the present invention, for a module in which a plurality of integrated circuit devices are mounted in parallel, the inductance generated by the unit length of a branched signal line on a motherboard is so set that it is smaller for a branched signal line a longer distance from its branching point to its distal end, and is so set that it is larger for a branched signal line having a shorter distance from its branching point to its distal end, so that the time required for transmission of a signal from the branching point to the distal end of each branched signal line is the same.

Abstract: An electromagnetic circuit breaker assembly, comprising at least one circuit breaker, is provided with a reverse polarity circuit that reduces the voltage presented to the terminals of the circuit breaker to which it is electrically connected when the terminals are further connected to a source of voltage in reverse polarity. The circuit breaker assembly is tripped due to the reverse polarity set-up, and remains tripped until the polarity is corrected. The electromagnetic coil is continuous provided with sufficient voltage so that the breaker may not be manually reset until the polarity is corrected. Preferably, the breaker is mechanically connected with another circuit breaker to create an assembly that will protect circuitry and devices against both a reverse polarity condition and an overload condition under normal operation. To this end, the reverse polarity circuit does not affect operation of the circuit breaker assembly if the polarity is in accordance with the normal set-up.

Abstract: The invention relates to a combination of a microrelay switch (1) switching off small overcurrents, and a short-circuit current limiter, for example a fuse link, a PTC thermistor 16 or a power breaker, for limiting or switching of large overcurrents.

Abstract: An adapter mechanism is configured to permit a previously known accessory device that had been configured to be used in conjunction with a previously known circuit breaker to be operatively connected with a different type of circuit breaker. The adapter mechanism includes a first interface that is engageable with a handle of the circuit breaker as well as a second interface that is engageable with a movable arm or a latch mechanism of the circuit breaker. The adapter mechanism further includes a support member upon which the first interface is rotatably disposed, with the support member being formed with a plurality of clips that permit the support member and thus the adapter mechanism to be removably mounted on the circuit breaker.

Abstract: An electrical switching device for fault-current, overcurrent and short-circuit current protection, has a contact point in a current path and a switching mechanism for permanently opening the contact point. The switching device further has a configuration for detecting the fault current, the overcurrent and the short-circuit current, and contains two permanent magnets and a core. The core is disposed between the like poles of the permanent magnets which point toward one another and one of which is fixed and the other is guided such that it can move. The permanent magnets are at least partially surrounded by a coil through which a fault, an overcurrent or a short-circuit current flows. When a current flow occurs in the coil, the magnetic field is changed causing a relative movement of the moving part, and the movement is transmitted to the contact point.

Abstract: A housing carries an electrical disconnect switch having movable contacts. A cover is mounted on the housing and has an opening allowing access to a control lever of the disconnect switch. Electrical conductors are connected to the disconnect switch within the housing and have a blade terminal portion extending exteriorly of the housing for connection to jaws carried on an electrical component mountable in an electrical watthour meter socket. Degassing ports are formed between the cover and the sidewall of the housing to allow any arcing gasses generated within the interior of the housing to escape from the housing. A handle is mounted centrally on the cover. An ejector handle is movably mounted on the cover and carries an ejector arm to separate the housing from an attached electrical component. A method of removing and remounting a watthour meter in a meter socket is provided, including sequence steps printed on the face of the housing.

Abstract: A protection system and single-phase control of high voltage with close loop dry insulation is provided. A detector detects the voltage through the influence of the electrical field in conductors, insulators and breakers, mainly, turning the field into an electronic signal. This signal is processed by means of a control and protection unit and responds through a trip mechanism so that if needed the contacts get opened or closed to allow or stop the flow of current through the system. A method to increase the life expectation of the contacts in the vacuum breaker chambers is also provided.

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 multi-pole protective device and system for electrical power transmission and distribution systems is provided that operates a multi-pole tripping system at ground level from a line-potential tripping device contained within each pole of the multi-pole system. The system includes multiple pole-unit assemblies each of which is totally self-contained and generates a tripping signal in response to overcurrent conditions to operate a ground-potential operating mechanism. In one arrangement, the pole units each include an internal line-potential tripping arrangement that communicates a trip signal to a ground-potential operating mechanism of the pole unit and associated pole units of the protective device arrangement. In a preferred arrangement, the line-potential tripping arrangement includes an insulated member that is moved to transmit the trip signal from line potential to ground potential.

Abstract: A new and improved type of ground fault interruption receptacle is mainly consists of an upper housing, a middle supporter and a lower holder. Two sets of female power-output socket 5, 6, a simulation test button (i.e. test button for fault detecting) and a reset button are disposed on the upper housing. A metal mounting plate is disposed between the upper housing and the middle supporter. At the two sides of the middle supporter is disposed a pair of metal conductors. Between the middle supporter and the lower holder is disposed a printed circuit board, and thereon a differential transformer within which an iron core is inserted, a reset guide member and a flat spring type of resilient off locking switch are arranged. Using the differential transformer and the resilient off locking switch, the receptacle of the present invention may detect whether the fault current exists and whether the damage of a certain element or member for power transmission occurs.

Abstract: An over-current and thermal protection device adaptable for use as an electrical interrupt and in a battery environment. The protection device has a pair electrical conductors, an electrically conductive resilient switch member engageable in contact with the conductors to define an electrical conductivity pathway. The switch member is actuated by a thermally responsive shape memory alloy strip and activatable in response to a change in temperature at a predetermined level to effect a change in the metallurgical state of the shape memory alloy and position of the engagement of the switch member with one of the conductors.

Abstract: An apparatus and method for interrupting the flow of electrical current in a line is disclosed. The invention provides for better limitation of current than can be achieved in the prior art. With effective current limitation, the magnetic force generated by the circuit breaker coil will not be excessive thereby reducing potential damage to the circuit breaker armature, increasing the interruption rating of the circuit breaker and end-use equipment and decreasing the interruption pressure within the circuit breaker.

Abstract: The high transient current sustained by arcing during opening of the main contacts of a miniature circuit breaker is commutated out of the bimetal by deflection of the bimetal in response to the overcurrent to close secondary contacts on the free end of the bimetal and on a low resistance by-pass conductor shunting the bimetal. The by-pass conductor can be extended toward the movable contact arm carrying the movable main contact to commutate some of the overcurrent into the by-pass conductor earlier in the opening sequence to reduce the energy input to the bimetal and reduce the force closing the secondary contacts.

Abstract: A circuit breaker includes main circuit contact shoes disposed in a circuit breaker case and urged by a contact spring, a contact opening and closing mechanism located above the contact shoes and including an opening and closing lever, a toggle link, an opening and closing handle and a latch, and an overcurrent tripping device located above the contact shoes. The toggle link includes a first link extending between the opening and closing lever and a toggle shaft located above, and a second link extending between the toggle shaft and the latch to overlap the first link in the V-form, and an opening and closing spring extends between the toggle shaft and a tip of a handle lever coupled to the opening and closing handle to extend downward. As a result, a space occupied by the contact opening and closing mechanism section in the height direction can be reduced to make the circuit breaker more compact.

Abstract: A relay multiplexing system which provides improved safety from hazardous voltage conditions. The relay multiplexing system comprises a relay multiplexer module and a terminal block which connects to the relay multiplexer module. The relay multiplexer module and corresponding terminal block incorporate a design according to the present invention whereby power can only be provided to the respective relays when the corresponding terminal block is connected to the respective relay multiplexer module. The terminal block is required to form an electrical path between the power supply in the relay multiplexer module and the relays. Thus, when the terminal block is removed from the corresponding relay multiplexer module, power is unable to be provided to the relays, thereby ensuring safety from hazardous voltages which could otherwise appear on exposed pins of the connector.

Abstract: A Hall effect sensor is transported to and away from a conductor to vary the sensitivity range of the sensor to current flow in the conductor. The device comprises a bracket supported on the conductor which holds a jack screw. At the lower end of the jack screw is a sensor block which holds the Hall effect sensor. The sensor block translates in a slide guide of the bracket, but is prevented from rotating. At the upper end of the jack screw is a knob for rotating the jack screw. Rotating the jack screw causes the sensor block to slide closer or farther from the conductor, which varies its sensitivity in measuring a magnetic field generated by a current in the conductor.

Abstract: A method and device for monitoring insulation and fault current in an electrical alternating current network. The differential current formed by vectorial addition is detected between at least two network conductors. Load-cut occurs when the differential current exceeds a specific threshold value. In order to increase safety and to protect human beings, the amount of alternating current contained in the differential current is detected as a first network variable, and the network alternating current between at least both network conductors and between at least one network conductor and an equipotential bonding conductor or a neutral conductor is detected as a second network variable.

Abstract: A combined ground fault and arc fault detector includes interrupting contacts which are opened when either an arc fault or a ground fault is detected. The detector includes a test circuit which creates a simulated fault and momentarily de-energizes the coil to test the detector and re-energizes the coil before the interrupting contacts open.

Abstract: In one aspect of the present invention, a residential circuit breaker is presented. The residential circuit breaker comprises an electronic residential circuit breaker having a selectable current rating which permits the user to easily set and reset the current rating depending upon the desired use and environment in which the current breaker is to be used. In another aspect, common power line carrier (PLC) communications are used to provide an effective signaling system for load control. In yet another aspect of the present invention, an interface between the electrical infrastructure and a home automation system for the purpose of load control is provided.

Abstract: A circuit breaker system 10 (FIG. 1) using electronic trip units 35 is disclosed. The electronic trip units 35 are coupled to a communications bus 30 whereby the electronic trip units 35 can be reconfigured, controlled, and/or monitored by a central computer 20. Further, the electronic trip units are coupled to a separate control power supply line 50 and to a zone selective interlock system.

Abstract: A circuit breaker system (100) providing a low impedance magnetic latch tripping scheme. The circuit breaker system (100) includes a trip unit (310) coupled to a switch unit (108). Trip unit (310) is coupled to an electrical circuitry and utilizes a current transformer (114) to sample a current conducting through the electrical circuitry. This current is processed into an input signal (126) suitable as an input to a trip circuitry (316) included in the trip unit (310). When a processor (322) senses an overcurrent condition in the input signal (126), processor (322) transmits a trip signal (128) to a switch (220) to initiate protection against the overcurrent condition, i.e., a trip of the electrical circuitry. Switch (220) permits a low release current to conduct through a low impedance electromechanical interface unit (218) such that the electromechanical interface unit (218) can actuate a mechanical opening mechanism included in the switch unit (108).

Abstract: The method relates to discriminating between an internal arc and a circuit-breaking arc established in the enclosure of a circuit breaker in a bay of a medium or high voltage metal-clad substation. The appearance of an internal arc is detected by a protection system which responds by transmitting a disengagement order to the circuit breaker, thereby causing a circuit-breaking arc to appear. The pressure of the dielectric gas inside the enclosure of the circuit breaker, is continuously measured and recorded so that after the instant at which the disengagement order is transmitted, it is possible to recover a first pressure value measured before the instant. The first pressure value is then compared with a second pressure value measured after the said instant in order to identify whether the internal arc was struck in the circuit breaker enclosure.

Abstract: A phase control switching system for controlling opening and closing timings of a power switching device to suppress the occurrence of an exciting rush current or a make-and-break surge voltage which is severe to system equipment such as a transformer, a reactor and a capacitor bank, or for controlling an arcing time of a circuit breaker to put the circuit breaker into operation for the arcing time leading to no-re-ignition or for the optimal breaking time. In the phase control switching system, a current measuring section or a current gradient measuring section is provided to measure a current value or a current gradient value of a current to be broken or introduced, and a reference phase detecting section estimates a current zero point of a current waveform on the basis of the measurements. Subsequently, a control section, upon receipt of an opening/closing command, an opening phase control operation using an arbitrary time point after the current waveform estimation as a reference.

Abstract: A method of communicating data with a plurality of electronic circuit breakers operatively connected in a power distribution system is disclosed and claimed herein. Each circuit breaker includes a communication port coupled to a network. The method comprises coupling a communication terminal, having a processing circuit and a first communication port coupled to the processing circuit, to the network via the first communication port; operating a first communication protocol for automatically addressing individual ones of the circuit breakers and for controlling message traffic on the network; and transmitting and receiving data on the network under control of the first communication protocol relating to the monitoring and control of the individually addressable ones of the plurality of electronic circuit breakers coupled to the network.

Abstract: A circuit interrupter of the type including an electronic trip unit for overcurrent determination includes a separate circuit to power the trip unit along with a Hall Effect or GMR Device to sense the current flow within the protected circuit. A removable option plug electrically interconnects with the trip unit to enable ground fault and arcing fault protection.

Abstract: The response time of a melting fuse is controlled or influenced by temporarily boosting a threshold level from a first constant value (I.sub.1) to a second dynamic value (I.sub.2) which is then caused to decay in a controlled manner during a fixed time between (t.sub.1) and (t.sub.2) and in accordance with a selectable decay function. If a current (m) flowing through the fuse exceeds the decaying threshold value a fuse blowing current is generated and supplied to the fuse, whereby the fuse blows sooner than it would have, if the excess current had prevailed for a long enough time between (t.sub.1) and (t.sub.X). On the other hand, the fuse does not blow in response to short duration transient excess currents that occur, for example at starting an engine. The engine start impulse which may be used to temporarily raise the threshold value from (I.sub.1) to (I.sub.2) and then cause said controlled decay.

Abstract: A circuit breaker receptacle is provided in which there is a circuit breaker to be used to protect a sub-circuit in an alternating current electrical circuit. A range plug is connected to the circuit breaker range processor to set an ampere value to be detected and interrupted by the circuit breaker. A variety of differently valued range plugs can be available so that the sub-circuit can be protected at various amperage values, thus permitting a plurality of individually protected sub-circuits to extend from a single main circuit. The sub-circuits will each be protected at a lower amperage value than the main circuit.

Abstract: A magnetic flux concentrator shield is disclosed for use with magnetic flux sensors in an overload relay for multiple pole electromagnetic contactor applications. The magnetic flux concentrating shield has slotted layers of laminated members. The layers have a series of pole shielding slots which concentrate magnetic flux generated by conductors carrying current through conductor apertures in each layer. Magnetic flux sensors are positioned within air gaps within each pole of the shield. By shielding the generated magnetic flux from reaching the magnetic flux sensor of another pole, the pole shielding slots minimize cross pole magnetic flux sensor interference.

Abstract: The load lugs electrically connecting circuit breakers employing electronic trip units with associated electrical distribution circuits are shaped to provide magnetic flux concentration to Hall effect current sensors within the electronic trip unit circuit. The Hall effect sensor is positioned within the shaped region of the load lug for optimum focus of the magnetic flux within each phase of a multi-phase electrical distribution system.

Abstract: A circuit breaker switch apparatus pluggable into a watthour meter socket includes at least one set of line and load contact terminals and a power disconnect for completing an electrical circuit between at least one line terminal and one load terminal. The power disconnect switch is responsive to a trigger signal to switch switchable contacts to an open position and maintains the switchable contacts in the open position as long as the trigger signal is present. The power disconnect switch is mountable in the socket adapter housing by a snap-in connection. Load jaw contacts are mounted on rigid bus bars which are connectable to the power disconnect switch by a snap-in connection. An insulating shield surrounds the line and load jaw contacts and conductors while providing apertures to allow the insertion of watthour meter blade terminals therethrough into contact with the jaw contacts.

Abstract: A circuit arrangement for limiting the current at make for a transformer wherein, in order to avoid the current peak at make when switching a transformer on, resistors are connected between operating voltage and the primary winding of the transformer. A test winding at the secondary side of the transformer is connected via a rectifier to the supply input of a contactor, so that the switches of the contactor close after the transformer is turned on and the resistors therefore no longer lie between operating voltage of the primary winding. PTC-resistors connected in series with the resistors assure that the resistors are not overloaded by the high-operating current of the transformer if the switches do not switch.

Abstract: A circuit interrupter of the type including an electronic trip unit for overcurrent determination which includes a small-sized iron core current transformer to power the trip unit electronics along with a giant magnetic resistor semiconductor (GMR) to sense the current flow within the protected circuit.

Abstract: Opening electrical contacts or electrical circuit interrupters. Particularly, a design for an electrical switch having opening electrical contacts which inhibit arcing. More particularly, a circuit breaker having a micro-contact interface comprising a contact with a plurality of contact points capable of handling high steady state currents conventionally handled by small to medium size molded case circuit breakers (i.e., 0.5 A.sub.rms to 400 A.sub.rms) at distribution voltage levels (120 V.sub.rms to 600 V.sub.rms).

Abstract: A multiphase circuit interrupter includes a plurality of power phase sections for establishing and interrupting electrical power carrying paths for a plurality of phases. Each power phase section includes first and second conductive regions which contact one another to complete the current carrying path for the phase. The second conductive region is movable to an interrupted position to interrupt the path. An interphase current carrying path is established between the power phase sections to conduct electrical energy between the sections following a trip event in any one of the sections. The interphase current carrying path may be established by a conductive element extending between the power phase sections. Channels may be formed in the interrupter housing between the power phase sections to communicate conductive plasma generated during separation of the contact regions from one another between the power phase sections.

Abstract: A new safety battery terminal and system for eliminating electrical power in event of an auto accident. The inventive device includes a metal clamp block dimensioned for coupling with a battery terminal of a battery. A terminal body is provided that is adapted for coupling with an electrical output line of an automobile's electrical system. The terminal body is positionable in alignment with the exterior wall of the clamp block. A fusible link is positioned between the clamp block and the terminal body.

Abstract: A circuit breaker and method for interrupting the flow of electric current in a line includes connecting separable contacts to a conductor in the circuit. An actuating device, actuated by an activating signal, is connected to the separable contacts to effect separation of the contacts wherein the flow of electric current in the circuit is interrupted. A current sensor, such as an iron core current transformer, senses the current in the circuit to provide a first sinusoidal signal. A bridge rectifier is connected to the current sensor wherein the first sinusoidal signal is converted to a rectified signal and power is derived from the rectified signal. An interface circuit connected to the rectifying network converts the rectified signal into a second sinusoidal signal for providing the activating signal to the actuating device at a predetermined magnitude of the first sinusoidal signal. The interface circuit includes generating a sign bit indicative of the polarity of the first sinusoidal signal.

Abstract: An arcing fault detection module (4) for detecting arcing faults in an electrical current distribution circuit (8) comprises a filter circuit (9) and an autocorrelation circuit (10). The filter circuit (9) is electrically connected to the distribution circuit (8) and samples current with the distribution circuit. The filter circuit (9) includes a band pass filter (12) to filter out fundamental and high frequency components from the sampled current, and a comparator (13) to convert the sampled current to a digital signal. The autocorrelation circuit (10) receives the digital signal from the filter circuit (9). The autocorrelation circuit (10) includes a plurality of shift registers (15-18) for storing the digital signal for a predetermined sample period, and a plurality of EXCLUSIVE-OR gates (35-37,41, 43, 44) and OR gates (38, 39) to detect odd and even harmonic signals.

Abstract: A system including a load center monitor (10) connected to a plurality of digitally enhanced circuit breakers (40) by a communication bus (26) provides monitoring and control of an electrical power distribution system. A user port (20) and a service port (22) provide a communication interface with an external computer. Visual indicators (34) and an audible alarm (30) provide for alerting persons to certain conditions in the system. Buttons are provided for CLEAR (38) and RESET (36) functions, and a diagnostic port (24) is also provided. The load center monitor (10) is operable to monitor the operation of the breakers (40) and download information therefrom in the form of historical data. Also, the load center monitor (10) can upload operating information to a breaker (40) in order to change the operation thereof.

Abstract: A miniature circuit breaker incorporating ground fault protection and arc fault protection includes a test mechanism including a ground fault test circuit for testing a ground fault detector trip mechanism, and an arc fault test circuit for testing an arc fault detector trip mechanism. A state machine circuit automatically controls the test mechanism to sequentially test both of the ground fault and arc fault detector trip mechanisms. A test push button is interconnected with the state machine circuit and, when pressed, initiates sequential testing of both of the ground fault and arc fault trip mechanisms.