Abstract: A fault-powered, processor-based circuit breaker tripping system employs a reliable low power trip indicator circuit that is normally powered from the tripping system. A liquid crystal display is used to indicate the status of the system, and a battery is used as a secondary power source after a trip terminates the power to the system. The battery is enabled by a manual switch or by a latch which responds to one of a plurality of trip signals from the processor. The latch also provides signals to a driver circuit to drive the LCD. Once enabled, the battery provides power to the latch and the LCD so that the cause of the trip may be displayed during a power fault. The manual switch can be used to select status signals to be displayed on the LCD, and to indicate the condition of the battery. The LCD includes a segment for indicating that the system is energized and power is being drawn from the current path but that amount of power is below all fault levels and insufficient to operate the system.
Type:
Grant
Filed:
August 31, 1989
Date of Patent:
February 18, 1992
Assignee:
Square D Company
Inventors:
Leon W. Durivage, III, William J. Bacher
Abstract: A residual current circuit breaker 1 has a partition wall 3 which separates an over-current protection device 4 from a residual current detection circuit 5. A plunger rod 24 extends through a bore 23 in the armature 21 of a coil 20 and is moved independently through the coil 20 to trip the breaker if a residual current is detected by the circuit 5. The plunger rod 24 is moved by a drive rod 31, the operation of which is controlled by a permanent magnet which retains the drive rod 31 retracted and an electromagnet which allows the drive rod 31 to drive forwardly under the action of a spring 32 in the event of a residual current being detected. The plunger rod 30 is reset by a reset lever 40 which is moved when an operating handle 18 of the breaker moves from a non-tripped to a tripped position upon tripping of the breaker.
Abstract: A circuit breaker control system includes a motor driven fork assembly, activated from a remote location, for simultaneously opening all of the breaker load contacts and locking them in an open condition. A DC voltage is selectively applied to energize the reversible DC motor. The switch at the remote location can be operated to enable a user-customer to return the breaker to operable condition at the breaker site. This is accomplished with an SCR circuit that is enabled by the remote switch and actuated by the user to operate the motor in a reverse direction to release the load contacts.
Type:
Grant
Filed:
September 29, 1989
Date of Patent:
January 21, 1992
Assignee:
Square D Company
Inventors:
John M. Winter, Jerry L. Scheel, Matthew D. Sortland
Abstract: An assembly frame having first and second frame plates secures the movable parts of a breaker assembly together for ready assembly of the breaker assembly in a housing. A pivot pin supports the trip lever between the frame plates. The movable contact carrying blade has an elongated hole through which the pivot pin passes, the elongate hole forming a floating point for the pivot pin.
Type:
Grant
Filed:
July 17, 1990
Date of Patent:
December 24, 1991
Assignee:
Square D Company
Inventors:
Willard J. Rezac, Thomas A. Edds, James Early, Martin Donnellan, Lowell D. Smith
Abstract: An electrical distribution load center consists of a non-conductive enclosure and a circuit breaker bus bar support panel that are interconnected by interlock members that can be snap-fitted to secure the two panels to each other. The support panel also has a latch member so that the bus bars can be mounted onto the panel in a heat-staking, insert-molded or snap-fit arrangement. The support panel also has elements for locking the circuit breakers onto the panels in conducting contact with the bus bars. The enclosure and the support panel are enclosed by a non-metallic trim panel that has a non-metallic door hinged thereto and which carries a latch for latching the door to the trim panel.
Type:
Grant
Filed:
July 19, 1989
Date of Patent:
December 10, 1991
Assignee:
Square D Company
Inventors:
Terrance A. Cassity, Jeffrey O. Sharp, William Sellers, Frank R. Wilgus
Abstract: A power control relay has a pair of solenoids one of which is briefly energized to open a pair of contacts and the other is opened briefly to close the contacts. A mechanical linkage maintains the contacts in their closed and open positions in the absence of solenoid energization. In a preferred embodiment of the invention, the solenoids drive a cam back and forth between two stable positions. The cam toggles an arm which opens and closes the power switch contacts.
Abstract: A wire-jumper assembly including an electrically insulating base having an insulating layer. A first conductor plate is positioned below said insulating layer, and a second conductor plate is positioned on top of said insulating layer. The conductor plates each include extension contacts directed outwardly from the base. The wire-jumper assembly also includes a pair of terminal lugs connected to said first conductor plate and said second conductor plate, respectively. A lead wire is secured to each of the terminal lugs. An additional cover can be installed on top of the wire-jumper assembly to provide safety from accidental contact.
Abstract: A fault-powered, processor-based tripping system includes a solenoid for interrupting a current path in response to a trip signal generated by a processor. The processor analyzes current provided by a current sensor, by way of an interface circuit, to determine when the trip signal should be generated. A power supply provides a reference signal to the processor to indicate the amount of power it is capable of delivering to the solenoid. Before attempting to engage the solenoid, the processor checks the level of the reference signal to determine whether or not the power supply is at that time capable of supplying the solenoid with a sufficient amount of power to effect interruption of the current path thereby avoiding a power loss by inappropriate engagement of the solenoid. If the power level is sufficient to engage the solenoid, the processor generates the trip signal to interrupt the current path.
Abstract: A motor and manual actuated switch includes a motor control circuit for controlling the motor to rotate in either a clockwise or counterclockwise direction to actuate a mechanical switch between the open circuit and short circuit states. The control circuit includes a capacitor coupled in series with the motor winding to form a series circuit and a control switch for connecting a source of d.c. power across said serial circuit when in a first position and a short circuit across said series circuit when in a second position. When the control switch is moved to the first position, the capacitor charges, causing a current to flow through the motor winding during the charge time, thereby causing rotation in one direction. When the control switch is moved to the second position, the capacitor discharges through the winding, thereby causing opposite current flow and shaft rotation.
Abstract: A voltage-to-frequency converter is provided for generating a frequency which is proportional to the square of the input voltage provided to the converter. Since the input voltage is correlative to current flowing in a conductor, the output frequency exhibits a proportionality similar to the relationship between the temperature of the conductor and the current flowing in it. The arrangement includes two charging circuits which receive the input voltage and are alternately charged as a function of the input voltage. While the first charging circuit charges to a predetermined voltage, the second charging circuit discharges. Upon exceeding the predetermined voltage, the output of a flip flop is set to discharge the first charging circuit, and to charge the second charging circuit. When the second charging circuit charges to a predetermined voltage, the output of the flip flop is reset, so that the first charging circuit charges again.
Abstract: A power supply incorporating a fault detection circuit controlling a circuit breaker is described. The power supply is isolated from relatively large applied DC voltages. This isolation is provided by a coupling capacitor in each of the line leads. The tripping energy for the circuit breaker can be provided either directly from the full wave rectifier output, or directly from the line lead or leads. In the case of the former, a reservoir capacitor may be used for storage of charge for tripping of the circuit breaker.