Abstract: Each pole of a multi-pole circuit breaker is equipped to individually separate the circuit breaker contacts within each pole upon overcurrent occurrence. A digital processor within the circuit breaker trip unit determines the occurrence of zero current crossing of phase current within the individual poles and initiates contact separation at zero current values.

Abstract: This invention relates to a high ampere-rated circuit breaker which meets the electrical code requirements of the world market. The charging of the powerful operating springs controlling the circuit breaker contacts is made automatically by means of an electric motor. The circuit breaker operating handle connects with the operating springs upon stalling of the electric motor. An electrical switching arrangement is used to remove power from the motor operator unit at the completion of the charging cycle.

Abstract: The circuit breaker interlock arrangement of the invention utilizes a pair of detector assemblies, one mounted on the rear surface of each one of a pair of first and second adjoining circuit breakers and interconnected by means of an elongated rod. The operating mechanism tripping plunger rod in the first circuit breaker trips the associated first circuit breaker operating mechanism to open the first circuit breaker contacts when an attempt is made to close the first circuit breaker contacts when the second circuit breaker contacts in the second circuit breaker are already closed, and vice versa.

Abstract: A motor controller unit of the type providing optimum motor operation and protection is configured to determine phase rotation correction during motor start-up without stopping and re-configuring. The effects of heat on the squirrel cage (amortisseur) and motor field windings are accurately and automatically determined on a continuing basis to deter nuisance trip occurrence during motor start and restart operations and to prevent damage to the motor windings during continuous motor operation, respectively.

Abstract: Circuit breaker arc exhaust apertures in the line end of the circuit breaker case transfer arc gases from the circuit breaker interior during overcurrent circuit interruption. A flexible shield protects the circuit breaker terminal lug from arc gas contamination.

Abstract: A circuit breaker shunt trip accessory unit contains a solenoid driven plunger that interacts with the circuit breaker operating mechanism to interrupt circuit current by means of an external signal. A mechanical override feature insures operation of a blocked solenoid plunger once the source of the blocking is removed.

Abstract: A field-installable circuit breaker trip actuator unit includes a flux shifter unit that interfaces with the circuit breaker operating mechanism and is installable without dismantling the circuit breaker components. The flux shifter unit responds to an electronic trip unit to articulate the circuit breaker operating mechanism and separate the circuit breaker contacts upon occurrence of an overcurrent condition. A reset arrangement allows the trip actuator unit to be automatically reset upon completion of the contact separation process.

Abstract: An interlock arrangement between a pair of industrial rated circuit breakers in adjoining circuit breaker compartments utilizes a pair of circuit breaker interlock units, one mounted on the rear surface of each circuit breaker. A corresponding pair of compartment interlock units are arranged within the circuit breaker compartments for interaction between the two circuit breaker interlock units to open the contacts within one of the circuit breakers when an attempt is made to electrically connect the circuit breaker within one compartment when the circuit breaker in the adjoining compartment is already electrically connected within the adjoining compartment.

Abstract: A remote closing operator is positioned within a circuit breaker enclosure to allow remote operation of the circuit breaker operating mechanism to close the circuit breaker contacts. A closing solenoid and associated logic circuit controls the state of the contact closing springs. The solenoid is energized to initially release the contact closing springs and is later prevented from operation upon any further attempt to release the contact closing springs after the contacts are closed.

Abstract: A field-installable circuit breaker trip actuator unit includes a flux shifter unit that interfaces with the circuit breaker operating mechanism and is installable without dismantling the circuit breaker components. The flux shifter unit responds to an electronic trip unit to articulate the circuit breaker operating mechanism and separate the circuit breaker contacts upon occurrence of an overcurrent condition. A reset arrangement allows the trip actuator unit to be automatically reset upon completion of the contact separation process.

Abstract: A circuit breaker thermal-magnetic trip unit for arcing fault detection includes a current transformer having a gapped magnetic core arranged around the load side of the trip unit. The bimetal within the trip unit is positioned abutment with the gap in the transformer core to thereby heat the bimetal causing the bimetal to trip and separate the circuit breaker contacts.

Abstract: A field-installable circuit breaker trip actuator unit includes a flux shifter unit that interfaces with the circuit breaker operating mechanism and is installable without dismantling the circuit breaker components. The flux shifter unit responds to an electronic trip unit to articulate the circuit breaker operating mechanism and separate the circuit breaker contacts upon occurrence of an overcurrent condition. A reset arrangement allows the trip actuator unit to be automatically reset upon completion of the contact separation process.

Abstract: A method and apparatus of the present invention includes a common node of a power line communications system for individually performing the register functions for a plurality of electrical metering devices operably connected to the node. The power line communications system includes at least one node having a plurality of registers, a respective one of which is associated with a respective electrical metering device. The electrical metering devices connected via the power lines to the node measure the power consumption of the electrical load associated therewith and transmit a signal indicative of the measured power consumption to the node and, in particular, to the respective register of the node associated with the electrical metering device. The node individually determines the power consumed by each electrical load operably connected to the node based upon the received signals. The results of such calculations are stored in the register associated with each respective electrical metering device.

Abstract: A modular plastic trip bar assembly joins separate single pole molded case circuit breakers into a single multipole circuit breaker. The addition of the trip cam to the trip bar assembly allows four and five pole combinations to operate in unison.

Abstract: A circuit breaker position switch unit is mounted to the sidewall of an industrial type draw-out circuit breaker enclosure to indicate whether or not the circuit breaker is electrically-connected within the enclosure. A time dwell is provided by the structural arrangement of the switch actuator plate with respect to the position indicator bracket. The position switch finds application where a number of circuit breakers communicate with a central processor control unit.

Abstract: An integrated circuit breaker is described having shunt trip capability along with automatic overcurrent protection through the circuit breaker trip unit and shunt trip module. The shunt trip module further provides auxiliary power to the trip unit and allows the trip unit microprocessor to report and record the shunt trip operation.

Abstract: Molded case circuit breaker accessories using slightly modified circuit breaker cases are described. Several of the accessories utilize a microswitch to provide remote indication of an auxiliary function. One modification of the circuit breaker case includes upstanding posts to capture and position the microswitch while a further modification utilizes the magnetic trip unit adjustment screw and a support plate.

Abstract: A circuit breaker bell alarm reset mechanism interfaces between the circuit breaker operating shaft and the bell alarm plunger to directly contact the plunger in response to rotational logic provided by the operating shaft. Rotation of the operating shaft to reset the circuit breaker operating mechanism simultaneously motivates the reset mechanism to reset the bell alarm plunger.

Abstract: Line voltage and line current signals are sensed on a power line having at least one conducting path. The sensed line voltages and line currents are converted into a digital signal. A phase-to-neutral voltage signal and phase current signal are computed from the digital signal to thereby define a phase of the power line. An interval of orthogonality is determined from the sensed voltage and current signals, coinciding with passage of an integral number of cycles of a fundamental frequency reference signal which is computed from the computed phase-to-neutral voltage signal. A vector metering quantity is computed for the determined interval of orthogonality from the computed phase-to-neutral voltage signal and the computed phase current signal. The vector metering quantities to be computed may be identified and computed based upon an associated detent. The vector metering quantity is also computed based on an identified circuit topology.

Abstract: A magnetic flux concentrator trip unit for molded case circuit breakers in the form of a flux concentrator magnet arranged round the load strap at one end of the circuit breaker is positioned in magnetic proximity to an armature. Current transport through the load strap generates attractive magnetic forces to articulate the circuit breaker operating mechanism when the current exceeds a threshold value.