Abstract: A multi-zone audio distribution amplifier system includes positions for several stereo amplifiers which may be used as modular and cascadable amplifier units. The system is enclosed in a housing having a front panel with windows for exposing a set of led display circuits on the front side of the housing and easy access to the modular units on the rear side of the housing. Each modular amplifier unit includes a printed circuit board for an amplification circuit, a heat sink, and a loop-back port for cascading the amplifier units. An interface board includes support for the display and edge-connector receptacles for receiving each printed circuit board edge and for providing power to each of the amplifier units. Each amplifier unit is operable independent of the others, and the desired amplification may be selected by electrically cascading the amplifier units via the loop-back ports.

Abstract: For use within an electrical distribution system, a circuit arrangement is provided which includes a multitude of circuit breakers, each of which is operable by remote control in at least open and closed circuit positions. A circuit breaker control circuit is included and has a termination circuit which interprets circuit breaker control signals from an external switch device, a circuit breaker driver board which controls and monitors the multitude of circuit breakers, input means and a data path for receiving manual input instructions, a data port and a data path for receiving programming data from an external device, and a switch input data path, coupled to the termination circuit, for carrying circuit breaker switch instructions from the termination circuit. The control circuit responds to the manual input instructions, programming data and circuit breaker switch instructions according to a prioritization scheme.

Abstract: A combined current and voltage measuring sensor for measuring voltage and current on a primary conductor, the sensor including a cast resin body having therein a aluminum support, the support having an aluminum encasement mounted thereto. An air core coil is encapsulate with the encasement within the cast resin body adjacent a grooved portion in the cast resin body for maintaining the primary conductor in the top of the cast resin body. The groove and the aluminum encasement cooperate to precisely locate the primary conductor with respect to the air core coil. A keeper assembly mechanically maintains and locates the primary conductor in the groove and further provides an electrical connection from the primary conductor to the voltage measuring apparatus of the sensor. A corona shield encapsulated within the cast resin body is at the same potential as the conductor and is interposed between the air coil and the groove of the cast resin body.

Abstract: An improved miniature circuit breaker is provided which is adapted to improved automatic assembly of all components thereof. Key components of the breaker are individually and collectively designed to be susceptible to total Z-axis assembly. In particular, the magnetic-yoke and armature which comprise the current response mechanism for the circuit breaker are designed to interact with each other so that the magnetic armature can easily be Z-axis assembled onto the magnetic yoke.

Abstract: In an electrical distribution system for controlling current paths through a plurality of associated circuit breakers, a programmable circuit arrangement operates the circuit breakers by remote control in at least the open and closed circuit positions. The circuit arrangement includes an array of termination points which are used in sets, such that each set includes a plurality of termination points, wherein each set receives a remotely generated control signal for commanding the circuit breakers to open or close. A control circuit includes a microcomputer, which is coupled to the array of termination points and responsive to the remotely generated control signal, for controlling the circuit breakers between the open and closed circuit positions. The microcomputer reads the termination points, via an X-Y grid, by polling the X axis and reading the Y axis.

Abstract: A circuit monitoring system for a distributed power network employs waveform capturing techniques for efficient and highly accurate monitoring. The system includes a plurality of circuit monitors and a control station, which is coupled to each of the circuit monitors via a multi-drop communications link. Each of the circuit monitors is disposed adjacent an associated one of the branches in the network for sensing power parameters in the branches and for generating and transmitting data representing the power parameters to the control station The control station is used for generating monitoring commands to each of the circuit monitors to provide the system with full system control and evaluation capability. Each of the circuit monitors also includes EEPROM memory for storing and retaining operational data, sent from the control station, in the absence of power. This allows a microcomputer in the circuit monitor to read the retained data for analyzing the sensed power parameter.

Abstract: An improved miniature circuit breaker is provided which is adapted to improved automatic assembly of all components thereof. Key components of the breaker are individually and collectively designed to be susceptible to total Z-axis assembly. In particular, the trip mechanism including the trip lever, and the associated activation means, tension means and reset means are defined by elements designed to interact in a Z-axis assemblable fashion. The trip mechanism components are also designed for improved trip action and enhanced breaker performance in repeated OPEN, CLOSED, and TRIP operations.

Abstract: A system allows for transferring messages between microprocessor based devices, such as programmable logic controllers (PLC), and a host computer over an Ethernet communications network. At the host computer level, these messages can be directed globally or locally. The host computer can immediately obtain messages from a programmable logic controller without interruption of the execution of the PLC's ladder program. The host computer can also receive unsolicited messages from the PLC.

Abstract: An electrical disconnect switch having a viewing window for viewing the internal switching mechanism is disclosed. The viewing window utilizes gaskets, rivets, a substantially transparent viewing window plate, and a viewing window retainer to provide a dust-tight, water-tight and drip-tight viewing window.

Abstract: The low dissipation compact circuit breaker of the present invention selectively conducts breaker current in a circuit to be protected. The compact circuit breaker is in an enclosure surrounding at least a stationary contact and a moveable contact. This moving contact selectively assumes one of two bistable states, a contiguous closed state or a noncontiguous open state. A rotary operator including rotary members and a contact lever train selectively causes the stationary contact and the moveable contact to assume either a closed or an open state. A single solenoid for sensing breaker current in each phase causes the rotary operator to move the contacts from a closed state to an open state. Additionally, the solenoid for a faulted phase directly acts on a solenoid bell crank to cause the contact to begin to assume an open state in a trip operation, if breaker current reaches a preselected trip value in the faulted phase.

Abstract: There is provided an electrical enclosure that maintains a rainproof seal using a formed lip, an elongated nub, and barrel hinges with spaced apart members therebetween to allow vertical movement of the enclosure door.

Abstract: A circuit monitoring system for a distributed power network employs waveform capturing techniques for efficient and highly accurate monitoring. The system includes a plurality of circuit monitors and a control station, which is coupled to each of the circuit monitors via a multi-drop communications link. Each of the circuit monitors is disposed adjacent an associated one of the branches in the network for sensing power parameters in the branches and for generating and transmitting data representing the power parameters to the control station. The control station is used for generating monitoring commands to each of the circuit monitors to provide the system with full system control and evaluation capability. The system is capable of simultaneously sensing the waveform at each branch and sampling the waveforms for a predetermined number of sample points over an integral number of cycles so as to provide an efficient yet accurate implementation.

Abstract: In a panelboard for controlling current paths through a plurality of associated circuit breakers, a panelboard enclosure includes circuit breakers which each have a side facing a front side of the enclosure and including a multi-sectioned user interface circuit, that is configured to communicate with at least one of the circuit breakers. The interface circuit includes a first circuit section and a second circuit section. The first circuit section is located adjacent the back wall of the enclosure and behind the second circuit section, and the second circuit section includes communication means for allowing an operator at the front of the enclosure to communicate with the circuit breakers. This arrangement minimizes heat in the back of the enclosure, provides control and monitoring functions at the front of the enclosure and allows room for additional circuitry in the back of the enclosure.

Abstract: In an electrical distribution system for controlling current paths through a plurality of associated circuit breakers, a programmable circuit arrangement operates the circuit breakers by remote control in at least the open and closed circuit positions. The circuit arrangement includes a termination circuit for receiving different kinds of remote control signals, each of which is associated with one of the circuit breakers for commanding that each of the circuit breakers open or close its associated current path. The arrangement also includes a programmable controller, which responds to each of the different kinds of remote control signals and to a user-defined program indicating the kind of remote control signal which commands the associated circuit breaker, for generating control signals. An interface circuit then responds to the generated control signals by controlling the circuit breakers between the open and closed positions.

Abstract: There is provided a circuit that protects the electronic tripping circuitry of a circuit breaker system from external transient high voltages and prolonged high voltage faults. The circuit preferably includes a transzorb that conducts in response to receiving a voltage signal having a magnitude greater than the breakdown voltage of the transzorb. This transzorb clamps the output voltage to its breakdown voltage. The circuit also includes a fuse that is designed to blow in response to a prolonged high voltage fault.

Abstract: The present invention relates to a distribution board for electrical power which provides rear electrical access to connect busbars and switch modules together. The distribution board includes a framework for supporting electrical components, a switch compartment for receiving at least one switch module, and a terminal compartment for connecting outlet terminals from the switch module to outgoing lines. The present invention also includes a switch unit which utilizes a housing having a rear face. The rear face incorporates both input and output terminals.

Abstract: A programmable logic controller system having the capability of controlling up to 64 clusters of peripheral controllers, wherein each cluster has up to seven racks of peripheral controllers, each rack having up to 16 individual peripheral controllers. Excepting for the cluster containing the programmable logic controller, each cluster is coupled to the programmable logic controller through an ethernet cable to a cluster controller. Each of the seven racks of peripheral controller cards is connected to its respective programmable logic controller or cluster controller directly (for the first rack) or through a local rack adaptor (for the other six racks). The programmable logic controller generates data, address and control signals which are used by the peripheral controllers to operate machines and equipment on an assembly line.

Abstract: A circuit monitoring system for a distributed power network employs waveform capturing techniques for efficient and highly accurate monitoring. The system includes a plurality of circuit monitors and a control station, which is coupled to each of the circuit monitors via a multi-drop communications link. Each of the circuit monitors is disposed adjacent an associated one of the branches in the network for sensing power parameters in the branches and for generating and transmitting data representing the power parameters to the control station. The control station is used for generating monitoring commands to each of the circuit monitors to provide the system with full system control and evaluation capability. The system is capable of simultaneously sensing the waveform at each branch and sampling the waveforms for a predetermined number of sample points over an integral number of cycles so as to provide an efficient yet accurate implementation.

Abstract: A molded plastic current limiting circuit breaker having for each pole, a stationary and movable contact separable upon occurrence of a current higher than a predetermined level. The stationary and movable contacts are positioned inside an over-molded magnet opening to greatly increase the magnetic repulsion force between them and rapidly accelerate their separation by concentrating the magnetic fields generated upon an occurrence of a high level short circuit. The over-molded magnet is composed of a plurality of steel plates grouped together and being over molded with a thermoplastic material. The thermoplastic material has grooves integrally formed therein for retaining insulator inserts that protect the thermoplastic material during separation of the stationary and movable contacts.