Abstract: The present invention provides a circuit breaker assembly having a base, cover, and switch handle adapted to withstand an external force applied to a lever of the switch handle. During normal operation the handle rotates on small-diameter pivots in elongated bearing slots. Under abnormal conditions that occur when the lever of the switch handle is inadvertently struck, such as when the circuit breaker is dropped on the lever of the switch handle, the pivots slide in the elongated bearing slots. The force is borne by large-diameter hubs which come in contact with mating bearing surfaces. Thus, the pivots are not shorn off during such incidents, which would damage the circuit breaker.

Abstract: A communication system between a programmable logic controller and a network of a plurality of remote input/output repeater modules uses a synchronous serial communications protocol. The programmable logic controller contains a transmitter module for generating a data packet containing the state of an output device connected to a remote input/output repeater module coupled to the network. A receiver module receives and decodes a returned modified data packet that indicates the state of input devices connected to the same or other remote input/output repeater modules also coupled to the network. The remote input/output repeater modules receive and decode the data packet to determine the state of the output devices that may be connected to it and modifies the data packet to indicate the state of its input device if there is one present. The modified data packet is sent to the next in-line remote input/output repeater module coupled to the network.

Abstract: An arrangement is provided for welding together current carrying members of an electrical distribution device which are made of similar conductive material. The arrangement includes an electron beam gun capable of generating an electron beam sufficient to penetrate and heat the material, thereby providing mixing of the material to form a joint which is constructed substantially of a portion of each of the current carrying members.

Abstract: A bearing for maintaining a bobbin in relative position about a transformer core leg during the winding of a coil on the bobbin. The bearing is movable along the core leg such that a bearing surface of the bearing is positioned adjacent to but not touching each of two outwardly facing surfaces of two spaced apart flanges of the bobbin. The bearing surface is highly polished to reduce friction. The bearing surface preferably includes a circumferential ridge centered about the axis of the transformer core leg on which the bobbin is positioned. The outwardly facing surfaces of the two flanges each include a concentric groove shaped to complement the circumferential ridges of the bearing surfaces. When the bearing is in position the circumferential ridges are partially received within the concentric groove such that a small gap is maintained between the bearing surfaces and the outwardly facing surfaces.

Abstract: A process of manufacturing an insulator having a central core and an insulating body fitted tightly around the central core includes interposing a flexible coating layer between a part of the central core and the insulating body. The flexible coating layer fills in shrinkage cavities and compensates for a retraction effect caused by injected material used in forming the insulating body. The insulating body is achieved by overmolding the central core previously coated with the flexible coating layer with an injected insulating resin such as a thermoplastic or thermosetting resin. The insulator could be used as a capacitive divider or bushing insulator.

Abstract: The present invention provides a switch mechanism module and a line base module, useable separately or in combination, for an interior assembly of an electrical distribution device having a plurality of modules. The electrical distribution device has an enclosure with a handle external to the enclosure for operator control. The switch mechanism module and line base module include a modular housing having a generally planar base with upstanding side walls around the circumference of the base. The side walls have a top edge defining a mating surface. The modular housing is demountably secured to at least one adjacent module with a manually operated securement which is integrally formed with the modular housing.

Abstract: A guard for preventing movement of a handle by an operator from a locked position to a second position. The handle is coupled to an operating mechanism which controls a distribution device. The handle extends outwardly from the surface of the distribution device. The guard includes a cover which is configured to substantially enclose the handle while in the locked position. The cover is supported about the handle by abutting the surface of the distribution device. The cover is also configured to allow the handle to move from the locked position to the second position wherein the cover prevents an operator, but not the operating mechanism, from moving the handle from the locked position to the second position and the handle positively indicates the state of the operating mechanism between the positions. The guard also locks the cover to the distribution device.

Abstract: An elbow for changing the run direction of a pre-bussed rigid conduit electrical distribution system. The elbow has a number of individually insulated electrical conductors each of which is formed to a predetermined angle. The conductors are enclosed within a hollow housing which is formed to the same predetermined angle such that it will enclose the electrical conductors. A uniform and continuous support is provided for that portion of each electrical conductor which is enclosed within the housing.

Abstract: A self-powered circuit interrupter arrangement for interrupting current in a circuit path uses a current-blocking component to ensure that an insufficient amount of accumulated power for actuating and completing interruption of the circuit path is not misused in an unwarranted attempt to interrupt the current path. The arrangement includes a current inducer circuit for providing a current signal having a magnitude corresponding to the current in the circuit path and a power supply operating from the current signal to provide a voltage signal of a predetermined value relative to common. A trip command circuit, in response to a fault detected in the circuit path, sends an electrical signal commanding that the circuit path be interrupted by using the voltage signal. The electrical signal is sent to an electrical latch located electrically in series with a coil of a solenoid mechanism.

Abstract: The present invention provides a circuit breaker having a terminal nut retainer 10 for securely holding a nut 65 in a fixed position adjacent and below a circuit breaker terminal 60. The circuit breaker is placed in a circuit by securing a source electrical connector to a source terminal and/or a load electrical connector to a load terminal. A screw 61 is used to fasten the electrical connector 67 to its respective terminal 60. The nut 65 for the screw 61 is held in a fixed position by the terminal nut retainer 10. The terminal nut retainer 10 has a nut retaining cavity 14 defined by walls which hold the nut 65 and keep it from turning while the screw 61 is tightened to establish a tight electrical connection between the connector 67 and the terminal 60. The terminal nut retainer 10 is held in position by a sliding and locking engagement between projections 30 and 34, respectively, on the terminal nut retainer 10 and slots 52 and 54, respectively, in the circuit breaker casing.

Abstract: The present invention provides an enclosure for housing a circuit breaker therein which utilizes a flange system to prevent enclosure components from separating from each other when an electrical fault occurs therein. The flange system includes flanges, on enclosure walls and doors, which slide into corresponding channels and interlock therein to prevent the components from separating and hot gases from escaping the enclosure when an electrical fault occurs.

Abstract: A molded plastic current limiting circuit breaker includes an interrupter assembly that includes an over-molded magnet, arc stack, baffle stack, and a chamber liner in which a trip unit is described.

Abstract: A programmable data link module (32) for use in a time division multiplexing control system (30) having a plurality of modules interconnected by a bus (40) for passing control signals between data link modules on a serial multiplex basis. Each module includes an integrated circuit (80) having signal conditioning circuits (180, 186 and 188) including a programmable hysteresis circuit (126), a power on reset delay circuit (190), a safety input inhibit circuit (220), a clock loss detect circuit (240), a safety output protection circuit (262), a data verifier (260), a polarity selector for a third output terminal (350), an input synchronizer (182 and 184), a combined mode/sync output terminal (110), a multiplex clock output terminal (108), a programming circuit (232) for accepting programming over the clock bus (44) and data bus (46), input/output word extender circuits (104, 106), a high voltage protection circuit (420) including a transistor (600) and a data bus integrity checker (630).

Abstract: A weld control system, supplied by a polyphase voltage source, consists of multiple and separate single phase weld controllers. The single phase weld control systems have their separate power modules combined into a single power module assembly for more efficient cooling and electrical interfacing. The single power module consists of a semiconductor switch for each phase of the polyphase voltage source and a single chiller plate for mounting and cooling the switches. The chiller plate functions as a heat sink and is machined to create a series of channels that become coupled together to form a continuous tube having a single input and a single output for a coolant liquid. A SCR pair, housed in a single package in a back-to-back configuration having an isolated base construction. The base has good thermal conductivity between the heat generating semiconductors in the package and the base.

Abstract: The present invention provides a mounting system for circuit breakers in an electrical panelboard assembly. The base and cover forming the circuit breaker casing has an integral foot extending from a bottom side. The foot is angled and has a notch on a side forming an acute angle with the bottom. The panelboard assembly has a bus cover adapted with a opening or opening to receive the foot. This secures the circuit breaker on one end, and a screw into a bus secures the circuit breaker on an opposing end. The bus cover has a rail which engages the notch in the foot. On an opposing side of the foot, a spring engages the foot and forces the foot into the rail. The spring is an integral part of the bus cover and is cantilevered at an angle to the main body of the bus cover. Ledges are formed integrally into the bus cover on opposing sides of the spring. The ledges prevent overstressing the spring while inserting the foot during installation of the circuit breaker.

Abstract: A circuit breaker (1) with a terminal connector (5). The terminal connector (5) has engagement means provided by outwardly extending male spade connectors (9a-9d) arranged in two spaced-apart offset parallel rows (7, 8). The circuit breaker (1) can therefore accommodate a maximum number of connectors (9a-9d) while allowing female spade connectors to be positioned regardless of orientation.

Abstract: An improved ground fault protection system is provided for protecting an electrical power distribution system having multiple sources and multiple grounds. In accordance with a preferred embodiment, an electrical power distribution circuit having a primary electrical circuit for distributing electrical power from a plurality of sources to a plurality of loads is provided with a ground fault protection circuit magnetically coupled to the primary circuit. The primary electrical circuit includes conventional main and tie buses for distributing power to the loads and switches or circuit breakers for interrupting power from flowing in the buses. The ground fault protection circuit includes current sensors, tripping functions or ground fault relays associated with each circuit breaker and a novel use of an auxiliary transformer. When a ground fault occurs, the ground fault protection circuit is capable of sensing and determining the specific bus in which a ground fault condition exists.

Abstract: The present invention provides an interior assembly for an electrical distribution device having a fuse for each phase in a circuit. The interior assembly includes a plurality of modules having an operating mechanism for opening and closing a switch contact. The switch contact is connected to each fuse and phase of the circuit. Each module has a housing and means for demountably securing one of the modules to at least one adjacent module. The securing means is manually operated and integrally formed with the housing of each module. The present invention also provides a method of assembling the interior assembly of an electrical distribution device having a fuse for each phase in a circuit. The step of the method includes manually and demountably affixing a plurality of modules to one another without discrete fasteners. The plurality of modules have an operating mechanism for opening and closing a switch contact. The switch contact is connected to each fuse and phase of the circuit.

Abstract: A programmable data link module is used on a time division multiplex data bus and includes a system master clock signal. The module is functional as an input device, an output device, or both as an input and output device. It receives data from the data bus during a selected time slot for a selected number of frames to control output devices connected to it. The data link module includes a clock loss signal for generating an inhibit signal when a loss of the master clock signal is detected. The inhibit signal will prevent any changes to the state of the output device during the duration of the loss of the master clock signal.

Abstract: The present invention provides a handle for controlling a switch mechanism of an interior assembly of an electrical distribution device having a plurality of modules. The electrical distribution device has an enclosure for housing the interior assembly. The handle includes a first piece having an elongated shape with two ends. The first end is adapted to be manually controlled by an operator and has a mating surface. The opposite end is secures the handle to the switch mechanism. A second piece has a complimentary shape for abutting the mating surface of the first piece at least near the first end. The first and second pieces are fastened without discrete fasteners.