Abstract: A field-installable circuit breaker trip unit conversion kit in the form of a flux shifter unit that interfaces with the circuit breaker operating mechanism 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. Expansion springs achieve tolerance take-up for different operating mechanism assemblies to correctly interface with the associated electronic trip unit.

Abstract: This high-voltage fuse comprises a tubular housing and a fuse subassembly within the housing with a core in the form of an elongated, cylindrical body primarily of silica sand particles bound together in a rigid, porous mass, a fusible element wound about the core, and connector assemblies at opposite ends of the core electrically connected to opposite ends of the fusible element. The fuse subassembly is closely surrounded by silica sand in the space between the housing and the subassembly.

Abstract: A wide range single-phase/polyphase switching power supply is presented. The power supply comprises first and second full wave bridge circuits. The rectified outputs of the bridge circuits are connected to a preregulator circuit, i.e., a FET circuit, where the primary input voltage from bridge circuits is limited. The output of the preregulator circuit is presented to a filter circuit. A current mode controller circuit operates at a fixed frequency with a variable duty cycle. An output of the current mode controller circuit drives the gate of a switching FET, at the fixed frequency and variable duty cycle. The aforementioned filtered voltage signal and the drain of the switching FET are connected across a first winding on the primary side of a flyback transformer. A second winding on the primary side of the flyback transformer is connected across Vcc, the supply voltage of the current mode controller circuit.

Abstract: A high strength operating cradle assembly for an industrial rated circuit breaker operating mechanism wherein the rotational action of the cradle about its pivot is controlled by interconnected operating mechanism links is disclosed. Axial positioning of the cradle on its pivot is maintained by the capture of a positioning track on the cradle pivot within a pair of guide rails on a guide pin extension on the cradle.

Abstract: A motor controller unit that employs standard motor contactors and electronic circuit breakers includes an electronic control module (ECM) for interfacing with the contactors and circuit breakers. Electrical connection with the circuit breaker electronic trip unit and the ECM is made by means of the circuit breaker rating plug. Electrical connection with the contactors and the ECM is made by means of externally-accessible terminal screws.

Abstract: A combined bell alarm and lock-out accessory is connected with the electronic trip unit that controls a high ampere rated circuit breaker. The accessory interacts with the circuit breaker operating mechanism to activate the bell alarm upon circuit interruption and to prevent the closing of the circuit breaker contacts until the accessory is manually reset. The circuit breaker lock-out mechanism interfaces between the circuit breaker operating mechanism and the accessory to insure that the contacts remain open until the accessory is completely reset.

Abstract: A motor control center of the type including a short circuit protective device such as a circuit breaker or fusible disconnect, and a motor starter for interacting with an electric motor includes a wiring access cabinet at the top of the control center. The multi-phase conductors within the access cabinet are protected by means of a pair of slidably-arranged access doors. The doors are arranged in a different position along the front of the access cabinet to access each of the individual phase conductors.

Abstract: A lightning arrester module is double-enclosed to insure adequate environmental protection to the enclosed varistors as well as to contain the internal components of the arrester upon severe fault conditions. The internal components including the varistors are compressed within one half section of the inner enclosure and can be handled and tested without disengagement. The other half section of the inner enclosure is positioned over the internal components to complete the inner enclosure before the outer enclosure is arranged thereover to complete the lightning arrester module assembly.

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 accomplished by operation of a ratchet and pawl assembly. A reset system interfaces with the charging system to reset the charging system after the operating springs have been discharged.

Abstract: A conversion kit in the form of a flux shifter unit that interfaces with the circuit breaker operating mechanism and is installable without dismantling the circuit breaker is proposed herein. The flux shifter unit responds to the electronic trip unit to articulate the circuit breaker operating mechanism and separate the circuit breaker contacts upon occurrence of an overcurrent condition. Tolerance take-up for various manufacture's designs is achieved by expansion springs while electrical interface with remote accessories and other electronic trip units is achieved by button-actuated switches.

Abstract: A fully automated circuit breaker saddle assembly in the form of a plastic support base having modular components that define the end and central sections of the support base. The components are snappingly fitted together and are retained by means of formations on the ends of the respective components. The metal circuit breaker stab assemblies are attached to the base by connectors integrally-formed in the base.

Abstract: A combined bell alarm and lock-out accessory is connected with the electronic trip unit that controls a high ampere rated circuit breaker. The accessory interacts with the circuit breaker operating mechanism to activate the bell alarm upon circuit interruption and to prevent the closing of the circuit breaker contacts until the accessory is manually reset. The circuit breaker lock-out mechanism interfaces between the circuit breaker operating mechanism and the accessory to insure that the contacts remain open until the accessory is completely reset.

Abstract: A Motor control center containing so-called "pilot" devices along with motor contactors and circuit interrupters mounts the pilot devices on a bracket that is received within the control center access door. The bracket is arranged to interact with the control center access door to automatically rotate the bracket in one direction when the access door is opened and to rotate the bracket in the opposite direction when the access door is closed.

Abstract: A current sensor has a closed loop magnetic flux concentrating ferromagnetic core with a gap and a central aperture for receiving a conductor. A Hall generator is positioned in the gap and a secondary winding is positioned on a portion of the core. Current flow in the conductor creates magnetic flux in the core which energizes the secondary winding to provide a power output. Magnetic flux concentrated in the gap causes the Hall generator to output a sensing signal that is proportional to the magnetic flux which is proportional to the current flow in the conductor. The single core is used to simultaneously produce a sensing signal proportional to alternating or direct current flow in the conductor.

Abstract: This invention relates to a high ampere-rated circuit breaker which meets the electrical code requirements of the world market. The circuit breaker electronic trip unit is contained within a recess in the circuit breaker cover and is interlocked with the circuit breaker operating mechanism to articulate the operating mechanism upon removal. The accessory units are contained within an adjoining accessory compartment recess within the circuit breaker cover. Rejection pins on the accessories insure that the correct accessories are connected within the corresponding accessory compartments.

Abstract: A surge arrester having a cylindrical housing with a throughbore, a metal terminal at each end of the housing, varistor elements located within the housing bore, and a vent within at least one terminal for venting arc-generated gases from the interior of the housing in the event of an arc being developed within the bore as a result of failure of a varistor element. The vent can be formed as a passage extending through one of the terminals from the bore to the exterior thereof via a substantially straight-line path that extends longitudinally of the bore. An electrode connected to the other terminal is spaced from the one terminal by a gap located externally of the insulating housing. The gap arcs over in response to receipt of arc-generated gases from the bore. The gap is located at the end of the housing of the one terminal.

Abstract: A secondary disconnect arrangement, in the form of a plug connector attached to the sides of a high ampere-rated circuit breaker assembly, interacts with a receptacle connector attached to the inner side walls of a circuit breaker enclosure. Movement of the circuit breaker in and out of the enclosure automatically connects and disconnects the plug connector from the receptacle connector. Terminals arranged on the plug connector on one side of the circuit breaker connect with internal circuit breaker components for communication and control functions, while terminals arranged on the plug connector on the opposite side provide connection between the internal circuit breaker components and remote auxiliary devices.