Eaton Corporation

Westinghouse Electric Corporation

Other

Denis A Mueller

Joseph C Engel

James Alan Bauer

Henry Anthony Wehrli, Iii

Robert Tracy Elms

Gary F Saletta

James D Smith

John Joseph Shea

David Glenn Loucks

Allan I Bennett

Robert T Basnett

Clyde O Peterson

Pamela M Maynard

Robert K London

Marlan L Winter

Robert L Cather

Daniel P Orange

Thomas A Wilsdon

Parker A Bollinger, Jr

Patrick J Hunter

Robert P Gibson

Jerry G Adams

Richard B Bell

John R Wilson

A contactor for selectively connecting at least one alternating current (AC) power line to a load and sourcing an AC current having periodic zero crossings includes a fixed contact; a movable contact mechanism; an operating mechanism for engaging and moving the movable contact to an open position in the absence of a closing signal; and a synchronized opening mechanism for disabling the closing signal in synchronization with a zero crossing of the AC current. The operating mechanism is disengaged from the movable contact, in a closed position, by a gap having a predetermined length in order that the contacts are separated at the AC current zero crossing. The contactor may further include a vacuum bottle for enclosing the fixed and movable contact therein. The movable contact may be carried within the vacuum bottle by a bottle stem which protrudes from the bottle and has a surface for engagement by the operating mechanism. The operating mechanism may include a crossbar and an arm having a surface for engaging and moving the bottle stem. The gap may be an overtravel gap between the arm and the bottle stem. The length of the gap may be determined by a length of the bottle stem or, alternatively, by a thickness of the contacts. The synchronized opening mechanism may include an electromagnet which has a coil which is energized in order to generate a closing current and which is deenergized in order to disable the closing current in synchronization with the zero crossing of the AC current. The length of the gap may be determined from a closing velocity of the arm multiplied by a period of the AC current zero crossings. The length of the gap may also be determined from a breakpoint in a plot of an overtravel gap versus contactor contact breaking cycle operations.

Synchronous contactor

Apparatus for monitoring power consumed from anywhere along the conductors in an ac power distribution system includes a housing with through passages through which the conductors extend. Toroidal coils mounted within the housing concentrically with the through passages sense the current in the conductors. Elongated electrically conductive screw fasteners threaded into support blocks mounted on a printed circuit board within the housing extend radially into the through passages to penetrate insulation on the conductors and to electrically contact and mechanically clamp the conductors thereby simultaneously providing a voltage tap and locking the housing to the conductor.

Monitoring device secured to power distribution system conductors

An improved PTC current limiting composition has been provided which comprises a chemically cross-linked thermosetting polyester resin and conductive particles dispersed in the resin. The thermosetting polyester resin is selected from the group consisting of polyethylene glycol fumarate, polypropylene glycol adipate fumarate, neopentyl glycol isophthalate fumarate, and neopentyl glycol phthalate fumarate. The conductive additive particles are selected from the group consisting of graphite and/or carbon black. The composition exhibits PTC behavior when cross-linked by a vinyl monomer selected from the group consisting of styrene, vinyl toluene and tertiary butyl styrene. Curing proceeds by free-radical addition across double bonds of the thermosetting polyester resin and is initiated by organic peroxides. Initial gelation which causes cross-linking but not final curing takes about 0.5 to 4 hours at a temperature of about 25.degree. C. to 125.degree. C. The final cure takes about 0.5 to 8 hours at a temperature of about 100.degree. C. to 160.degree. C. An effective amount of alumina trihydrate can be added to the current limiting composition to prevent dielectric breakdown, arcing and carbon tracking under high voltage conditions. It is respectfully submitted that the MPEP 608.01(b) states that abstracts should be between 50 and 250 words and up to 25 lines. Applicants' abstract in within these limits.

Positive temperature coefficient conductive polymer made from

A circuit controller for selectively connecting a power source to a load includes a non-overcurrent protective electrical switching mechanism and a conductive polymer current limiter connected in series with the load for limiting the current which flows through the switching mechanism whenever the power source is selectively connected to the load. The conductive polymer current limiter may include a plurality of parallel conductive polymer positive temperature coefficient (PTC) resistors. The circuit controller may include an electrical switching mechanism which, under short circuit conditions, remains selectively connected to the load. The short circuit current which is limited by the conductive polymer current limiter continues to flow through the electrical switching mechanism. The switching mechanism may include a contactor having separable contacts, and may further include a circuit interrupter, in order to provide a separate circuit disconnection mechanism. The electrical switching mechanism may have a coil and the circuit controller may include a voltage sensor. The conductive polymer current limiter may have an output which has a voltage substantially less than the voltage of the power source whenever the short circuit current flows from the power source and through the current limiter. The voltage sensor may be connected to the output of the conductive polymer current limiter and may deenergize the coil in order to open the separable contacts of the contactor and disconnect the power source from the load whenever the voltage of the output drops below a predetermined threshold. The contactor may be a motor-starting contactor.

Current limiting circuit controller

A controller incorporating a push button station controls a plurality of electrical contactors in a modular multicontactor system using three-wire serial data links. All information exchange is initiated and controlled by the controller using a simple four-byte protocol which places very little burden on the contactors. The controller can also communicate with and receive commands from devices on a network through an interface using the same four-byte message protocol, but with the interface acting as the master and the controller as the slave. When used in a reversing and two-speed motor controller configuration, the controller manages sequencing of the contactors, including delays, and passes thermal image data between contactors.

Digital modular microprocessor based electrical contactor system

In a multiple contactor installation where each contactor provides overcurrent protection, overload information in passed from one active contactor to the next as a percentage of the trip level of the respective contactors.

Electrical contactor system with transfer of scaled overload information

A PC computer monitors the energy consumed at a plurality of local stations placed behind the electrical meter of the utility company for individual billing of the local users, a bidirectional communication line being used between the PC computer and the plurality of local stations. A command from the PC computer causes the totalized energy to be stored at each station, and thereafter the PC computer derives individually the results for separate energy estimations and central billing.

Circuit breaker - associated backpack unit for lower-link communication

A pump controller coupling the electric motor of a cyclically operating well pump to a power line is arranged to measure instantaneous power consumption of the motor, to integrate the power consumption over pump cycles, and to assess the performance of the well and/or pump by using the total power consumption to estimate fluid flow. The controller determines a phase reference in the cycle of the pump by monitoring for a peak or zero crossing in the instantaneous power level, specifically the point at which the pump changes over from a power stroke to regenerative operation due to pump momentum. The integrated total power consumption is reduced by an offset factor representing frictional losses, and scaled to obtain an approximate fluid volume determination for the pump and well. The factors used for offset and scaling can be adjusted by calibration using at least intermittent measurements of actual fluid flow and fluid density. The offset factor representing friction can be monitored for deciding when maintenance is needed on the pump.

Rod pump flow rate determination from motor power

The first capacitor of a capacitive divider adapted for measuring the voltage on a bus bar utilizes the bus bar as one plate, the normal insulation provided on the bus bar as the dielectric and a first conductive layer applied over the insulation as the second plate. While a separate capacitor can be used for the second capacitor of the capacitive divider, preferably the first conductive layer serves as a common plate for both capacitors, with a second insulation layer applied over the first conductive layer forming the dielectric of the second capacitor, and a second conductive layer applied over the second insulation layer serving as the second plate which is grounded. The voltage on the common plate formed by the first conductive layer is applied to a voltmeter to provide a voltage reading proportional to the voltage on the bus bar. A particularly simple, compact combined voltage and current sensor is provided by aligning a mutual inductor current sensor with the integral capacitive divider so that the outer conductive layer of the capacitive divider serves a voltage shield for the current sensor.

Integral capacitive divider bus bar voltage measuring apparatus and

An installation for the dynamic burn-in testing of a plurality of digital circuits, and/or microcomputer-controlled circuits, mounted in a burn-in chamber for testing includes a personal computer; power supply for the digital circuits, and a bilateral line of communication between the PC computer and each of the digital circuits; the PC computer interrogating separately, and at will, any of the digital circuits as to their status and capability of changing status while retrieving any indication of a critical testing condition from any digital circuit, to determine a failure-free burn-in time.

Personal computer-based dynamic burn-in system

An electromagnetic contactor or controller is taught in which the voltage which is impressed across the electromagnetic armature winding is controlled with an algorithm to enhance the closing operation. A microprocessor is utilized to implement the algorithm.

Electromagnetic contactor with algorithm controlled closing system

A bidirectional motor has two electromagnetic contactors, one for forward, the other for reverse operation. Thermal protection is provided by a thermal image generator and a thermal protection unit in each contactor operating in tandem via a bidirectional line of communication keeping the thermal images in parallelism by one active contactor 'talking' to the inactive contactor, the 'listener'.

Electromagnetic contactor tandem control system for thermal protection

A master metering module is taught which utilizes a programmed microprocessor and externally operated switches to alert the module as to what kind of system is being monitored thereby. For example, is the system being monitored a .DELTA.-connected electrical system or a Y-connected electrical system. This is useful in providing output indications of line-to-line voltage or line-to-neutral voltage, for example. When measuring voltages whether line-to-line or line-to-neutral one voltage value is substituted from another. A differential amplifier is utilized to do this. In one case the differential amplifier subtracts one line voltage from another line voltage, but in another case it subtracts neutral or zero ground potential from a line voltage. A switching arrangement is provided which interconnects one terminal of the differential amplifier with the neutral input terminal and with a line input terminal through appropriate conditioning of the microprocessor.

Master metering module with voltage selector

A microprocessor control motor starter is utilized in which a capacitor-backed random access memory is utilized to store certain critical data about the status of a motor so that if the power supply voltage temporarily drops below a certain value the critical information will not be lost. The microprocessor which controls the motor attempts to reinitialize itself as in the case long term power outage. A subroutine is provided which determines whether the motor can immediately be placed in the state it was in before the power outage occurred, or whether an automatic restart may take place, or whether the motor must be operator restarted manually.

Growing community of inventors

Asheville, NC, United States of America

Denis A Mueller