Abstract: Apparatus for providing an accelerated linear motion to a circuit breaker operating handle during ON or OFF operation of the circuit breaker. The accelerated linear motion being applied to the operating handle at a particular point during its movement such that the moveable contacts of the circuit breaker are not delayed in their opening or closing due to slow movement of the circuit breaker operating handle.

Abstract: A circuit breaker includes a breaker enclosure, a plurality of conductor connections, and a temperature sensor. The breaker enclosure contains internal components that include a trip unit. The plurality of conductor connections electrically couple the trip unit to a plurality of power conductors. The temperature sensor is located to sense heat radiated by the conductor connections and is positioned inside the enclosure.

Abstract: A method and system to detect and evaluate harmonic distortion in an electrical power system is disclosed. A plurality of monitoring devices is installed in the electrical power system. The hierarchy of the electrical power system is received. Data indicative of harmonic distortion on the electrical power system is received from at least two of the monitoring devices. The data indicative of harmonic distortion is automatically aligned in a temporal or pseudo-temporal context. An electrical characteristic of the harmonic distortion from the data indicative of harmonic distortion is determined.

Abstract: A digital power metering system reduces spectral leakage when determining the frequencies present in a power signal by a technique that includes sampling the signal and performing a transformation from the time domain to the frequency domain. The system initially measures the fundamental frequency of the power signal, and samples the power signal at a known sampling rate to produce digital sample values representing the power signal. The system then determines whether the known sampling rate is within a preselected range of a rate that is coherent with the measured fundamental frequency. If the answer is negative, then the system resamples the signal at a rate that is coherent with the measured fundamental frequency to produce resample values representing the signal, so that the frequencies present in the power signal can be determined from the resample values.

Abstract: A DC motor phase estimation algorithm that estimates a speed-related harmonic frequency of a DC motor current under dynamic load conditions having known geometry parameters. The algorithm estimates the phase and magnitude of a complex coefficient in a complex single frequency adaptive filter that receives a primary signal from the motor current and estimates a reference signal using an incident frequency by adapting the complex coefficient to match the magnitude and phase of the speed-related harmonic component of the primary signal. The rate of change of the phase of the complex coefficient is determined by a phase-lock loop coupled to the adaptive filter to adapt a dynamic incident frequency corresponding to a single frequency component of interest in the primary signal. The incident frequency is extracted, and the motor speed is estimated using the extracted incident frequency and the known motor geometry parameters.

Abstract: A trip unit in a miniature circuit breaker includes a magnetic yoke and a bimetal mounted on the outside of the yoke. The bimetal is welded at one end to a load terminal that leads to a terminal connector and at the other end to a pigtail. The pigtail, instead of the bimetal, passes through the yoke for connection to the blade of the circuit breaker. To induce a higher magnetic field for faster tripping, a second pigtail may be passed through the yoke in which one end of the second pigtail is connected to the load terminal near the terminal connector and the other end is connected to the bimetal near the load terminal connection point. The load terminal may include at least two parts, one part including the adjustment screw and the other part including the terminal screw. These parts may be separated by air or an insulator.

Abstract: A circuit breaker lock-off device is side-mounted to a circuit breaker case in a tenacious engagement. The lock-off device has a generally planar body carrying a lock-off arm pivotable in a plane parallel to the body to place an engagement tab extending therefrom into a position for preventing movement of the breaker handle without being physically attached to the breaker handle. The lock-off arm and the body further have complementary rings for accepting a padlock shackle in the locked off position. The invention allows a rugged lock-off accessory which is field installable and which can accommodate various breaker handle geometries.

Abstract: An automated integrated monitoring (IM) algorithm that automatically puts data from a utility monitoring system into context by temporally aligning the data to a common reference point and by identifying the location of each monitoring device in a hierarchy relative to other devices. Frequency variation data is received from all meters. The data is automatically aligned to a common reference point, such as a precise zero crossing, using a cross-correlation algorithm to determine the time delay at which the data is most correlated. Once the data is aligned, power data is received from all meters in a hierarchy, and the monitoring system layout is auto-learned using a correlation algorithm to determine which two meters are most likely correlated with one another based upon their historical power readings. Once the layout is complete, additional decisions regarding hardware and software configuration can automatically be made by the IM algorithm.

Abstract: A method and system for determining whether arcing is present in an electrical circuit. The methods includes sensing a change in an alternating current in the circuit and developing a corresponding input signal, analyzing the input signal to determine the presence of broadband noise in a predetermined range of frequencies, and producing a corresponding output signal. The method further includes determining a type of load connected to the electrical circuit, based at least in part upon the input signal and the output signal, incrementing one or more of a plurality of counters in a predetermined fashion in accordance with the input signal and the output signal and determining whether an arcing fault is present based at least in part on the states of one or more of a plurality of counters. The method also includes decrementing one or more of the plurality of counters based upon a secondary analysis.

Abstract: An improved electrical equipment enclosure includes an electrical enclosure, electrical equipment in said electrical enclosure, said electrical equipment including one or more devices requiring a network connection to devices outside of said enclosure, and a network port mounted to said enclosure and accessible from externally of said enclosure and operatively coupled with said equipment requiring a network connection inside of said enclosure, for connecting said equipment with equipment outside of said enclosure.

Abstract: A bus to tap-off device interlock having a first position wherein the tap-off device can be installed or removed from the busway section and a second position in which an installed tap-off device can not be removed from the busway section and an uninstalled tap-off device can not be installed onto a busway section. The interlock is movable between the first and second positions by operation of an operating handle that controls the OFF or OPEN and ON or CLOSED state of an electrical disconnect device located inside the tap-off device.

Abstract: An independent automatic shedding system that automatically allows any combination of loads to powered under limited power availability (such as a standby power source) without overloading the generator or rewiring, while contributing to the stability of the power grid. A motorized disconnection actuation mechanism under control of a controller disconnects or recloses the contacts of a branch circuit breaker. A sensor detects the presence or absence of a power source and the type of power source, which is classified according to its type. A power source classification program is executed by the controller that interprets the sensor data and causes disconnection or reclosing of the disconnection actuation mechanism depending on a desired status (ON or OFF) of the branch circuit breaker when standby power is available. Conventional circuit protection is provided an optional advanced circuit protection such as ground or arc fault circuit interruption.

Abstract: An auto-learned hierarchy algorithm that learns the hierarchical layout of a power monitoring system. Historical power data from each meter is received and placed into a data table. The main is assumed to be at the top of the hierarchy and is designated as the reference. A check matrix is developed indicating whether a possible connection exists between each meter pair combination. A correlation coefficient matrix (CCM) is calculated based on the data table, and entries in which no connection is possible are zeroed. The column for the reference meter from the CCM is copied to a correlation reference array (CRA), and the meter having the highest correlation with the reference meter in the CRA is marked as connected to the reference meter in a connection table. That meter's power is subtracted from the data table and the procedure is repeated until all meters have been analyzed.

Abstract: A latching mechanism for a movable member mounted for movement between first and second positions. The latching mechanism includes a primary latching mechanism mounted for movement between a latched position where the primary latching mechanism engages the movable member to allow the movable member to move between the first and second positions, and an unlatched position where the movable member is disengaged for movement to the second position. A secondary latching element engages the first latching mechanism to hold the primary latching mechanism in the latched position, the secondary latching element being movable to move the primary latching mechanism to the unlatched position while remaining in engagement with the primary latching mechanism.

Abstract: In order to determine whether arcing is present in an electrical circuit, a sensor signal corresponding to current in said electrical circuit is processed. The sensor signal is filtered to determine the presence of noise in a predetermined frequency range and produce a corresponding filtered signal. The corresponding filtered signal is compared to a reference threshold voltage to generate an output signal potentially indicative of arcing. A selection is made of one from a plurality of available threshold voltages as the reference threshold voltage for use in the comparing operation. The detection operation supports either or both branch feeder arc fault detection and/or series arc fault detection.

Abstract: A terminal assembly for use in a circuit breaker. The terminal assembly includes a first member and a second member abutting the first member. The second member includes a pair of protruding arms to be inserted into a corresponding pair of recesses in a circuit breaker housing. Because the pair of protruding arms are inserted into the housing, the first member is protected against rotational force.

Abstract: An industrial human-machine interface device that permits speech-controlled navigation through a menu using a speech-recognition processor. The speech-recognition processor is coupled to a microcontroller and a display. The microcontroller is interfaced with a power metering device which monitors a power signal in a circuit. To obtain a reading of a characteristic of the power signal, the operator speaks a spoken keyword into a microphone of the human-machine interface device. The speech-recognition processor converts the keyword into an identification word which is outputted by the processor to the microcontroller. The microcontroller polls the output of the processor, and upon detection of an identification word, executes a function associated therewith. Menu navigation among consecutive or nonconsecutive menu levels is performed by speaking one or more predetermined keywords.

Abstract: An linear motion compensator for translating a particular amount of linear movement produced by an input device into a particular amount of linear movement required to properly operate an output device, without causing damage to either the input device or the output device.

Abstract: A switching mechanism provides sequential switching of first and second circuit breakers to enable switching between a primary power supply and a backup power supply. The switching mechanism comprises an actuating mechanism to sequentially actuate a pair of circuit breakers. The actuator mechanism including a shock absorber to absorb energy due to switching of one of the first and second circuit breakers.