摘要:
A joint pack includes one or more phase members that utilize integrated standoff spacers that protrude and come into contact with opposing conductor plates to maintain a phase space between the phase members. The spacers are located along the insulating plates of the phase members away from the phase member's axial sleeves and protrude through apertures in the conductor plates disposed on the phase members, in which the standoff spacers also provide a barrier that prevents phase-conductors from being inserted too far within the phase space. The phase members include axial sleeves that fit within one another during assembly to form a nesting arrangement, thereby reducing the overall size of the joint pack while satisfying standards. The axial sleeves can be distinctively designed such that the phase members must be assembled in a predetermined order, with no components being omitted, to form the joint pack.
摘要:
A current sensor assembly used for detecting ground faults, which includes an enclosure surrounding the current sensor for focusing the magnetic flux produced by conductors passing through the current sensor assembly away from the conductors, thereby reducing load-shift error and producing more accurate current readings for ground-fault sensing. The enclosure has two half members that are secured together to form a toroid-shaped shell that surrounds a toroidal core of the current sensor. A secondary winding and an optional test winding is wound around the toroidal core, and the ends of these windings exit one or more apertures formed in the enclosure. The half members have rounded profiles where the flat surfaces transition into different planes so that the magnetic flux does not encounter any sharp edges or transitions inside the enclosure as the flux flows away from the conductors.
摘要:
A multi-pole circuit breaker comprising a single main housing containing multiple circuit breakers for protecting multiple branch circuits. Each of the circuit breakers comprises a single line terminal for receiving electrical current from a utility line, a plurality of load terminals for supplying electrical current from the single line terminal to a plurality of branch circuits via load lines, and a plurality of neutral terminals for receiving electrical current returned from the branch circuits via neutral lines Line conductors inside the main housing connect the line terminal to the plurality of load terminals. Sensors inside the main housing generate signals representing characteristics of the electrical current flow in the branch circuits, and a signal processor uses the signals generated by the sensors for detecting abnormal conditions in the branch circuits and generating trip signals in response to the detection of an abnormal condition. A single tripping mechanism between the line terminal and the load terminals receives the trip signals and interrupts the flow of current to the branch circuits in response to a trip signal.
摘要:
A low voltage DC power supply is provided in a load center for distributing electrical power from electrical power utility lines to multiple branch circuits via a load center bus connected to the utility lines, each of the branch circuits having a circuit breaker coupled to a processor that is shared by multiple circuit breakers in the load center. The low voltage DC power supply includes a switch mode low voltage power supply connected to the processor for supplying the processor with a DC power input, and a line-derived power supply and a fault-derived power supply coupled between the utility and the switch mode power supply for supplying DC inputs to the switch mode power supply. The magnitude of electrical current supplied to the multiple branch circuits from the load center bus is determined by producing signals representing the current levels in the bus at successive locations on opposite sides of each connection of the bus to the multiple branch circuits, and determining the current supplied to each branch circuits from those signals.
摘要:
A system, method, and computer program product for predicting operation for physical systems with distinct operating modes uses observable qualities of the system to predict other qualities of the system. Independent variables including temperature or production volume are observed to determine the degree to which a dependent modeled variable, including energy load, is influenced. Partition variables representing operating conditions of the dependent variables are defined as discrete values. Reference datasets with coincident values of the dependent variable, independent variable, and partition variables are received, and models are created for each discrete value of the partition variables in the reference dataset. Each model is populated with the values of the dependent variable and the independent variable. The dependent variable is modeled as a function of the independent variable. Model accuracy is evaluated by processing new input data to generate output data that includes values of the coincident dependent variable, the independent variable, and the partition variable from the input dataset.
摘要:
A method for automatically updating an existing firmware file stored in a memory of an intelligent electronic device (IED) communicatively coupled to a network in a monitoring system. The IED downloads from a remote server to the IED an update file that includes a version of a firmware file and a filename of the firmware file. The IED determines whether the firmware version specified in the update file is updated compared to a version of the existing firmware file. If the firmware version in the update file is greater than the existing version, the IED communicates to the remote server an instruction to download to the IED the updated firmware file specified in the update file. The IED receives from the remote server the updated firmware file. If a criterion is satisfied, the IED automatically updates the firmware file stored in its memory with the updated firmware file.
摘要:
A bimetal in a circuit breaker can deflect in a first direction or a second direction depending upon conditions. If the bimetal deflects in the second direction it can increase the force necessary to operate a trip mechanism of the circuit breaker. A yoke stop helps to control bimetal deflection forces and thus, the amount of force necessary to operate the trip mechanism. This allows better control, size, and selection of operating parts for the circuit breaker.
摘要:
A circuit breaker includes a breaker housing, a transformer housing, and a plurality of conductor locators. The transformer housing is enclosed within the breaker housing and has an opening for receiving a plurality of conductors. The plurality of conductor locators is desirably located adjacent to the transformer housing and is movable between an open position and a closed position. The conductors are generally centered in the opening of the transformer housing when the conductor locators are in the closed position.
摘要:
An intelligent electronic device (IED) integrating a power metering unit (PMU) and a merging unit that combines signals from both analog transformers and digital transformers into a set of merged digital samples. Analog current/voltage signals from analog CTs/PTs are received at the IED's analog inputs and converted to digitized samples. Digital current/voltage samples from digital CTs/PTs are received via point-to-point connections at digital inputs of the IED. A tagging unit applies metadata tags to the digitized and digital samples. The metadata tags include the transformer providing the input signal, sampling rate, primary and/or secondary timestamps, scaling values, calibration values, and/or the location of the IED in the electrical system. The PMU performs metering and/or power quality calculations on the samples, and the calculation results are formatted and transmitted via a master-slave protocol to a requesting master. A grouping unit groups the merged samples into default or custom groupings, which are formatted and transmitted over a network via a publish-subscribe mechanism.
摘要:
A high ampacity busbar includes a pair of oppositely facing bowl-shaped conductors, each of whose cross sections resembles half of a hexagon or an open isosceles trapezoid, separated by an air gap in both horizontal and vertical configurations. The air gap increases cooling efficiency by natural convection by exposing more surface area of the conductors directly to the air flow within the electrical distribution equipment cabinet. As a result, the overall temperature of the bus system is reduced. The shaped conductors have smoother transitions presented to the electrical current between the bends of the conductors. These smooth transitions improve current distribution throughout the conductor, reducing skin effects. As a result of improved thermal dissipation and reduced skin effects, the amount of copper needed to maintain the same ampacity is significantly reduced. Magnetic shields can be placed between adjacent busbars, reducing proximity effects.