Abstract: A Fusible electric switch is herein described for increased ratings within industrial electrical distribution circuits by the provision of an arc exhaust gas controller. The arc gas controller cools and deionizes the arc gases that are generated upon separation of the switch contacts and exhausts the gases in a predetermined direction outside the switch enclosure. Fuse pullers are arranged at one end of each of the switch fuses to facilitate both installation and removal of the fuses.

Abstract: A locating and alignment pin provided on the bottom of an electric busway switch provides immediate location of the switch connector clips with respect to the busway connector tabs while, at the same time, aligning the switch interlock with the corresponding interlock slot formed within the busway housing while adding to the mechanical support between the electric busway switch and the busway housing. The locating and alignment pin is received within a corresponding locating aperture formed in the top surface of the busway housing next to the busway plug outlet box.

Abstract: A modular marina power pedestal and light pedestal enclosure is fabricated from a pair of opposing flanged plastic sidepieces that are sized to accept both lamp enclosures as well as electrical power centers. A wide variety of customer options that include power receptacles, telephone connectors, metering facilities and water hook-up are available with slight modification. Existing lamp enclosures and power centers are received within the enclosure without modification.

Abstract: An electric power bus removable joint includes three spacer-connectors that automatically align the intervening splice plates and insulative plates used to electrically connect between adjoining busway sections. The spacer-connectors automatically attach between the opposing joint face plates without requiring any additional fastening means.

Abstract: A current limiting circuit breaker having a pair of separable contacts closely spaced for electrodynamic repulsion upon the occurrence of a short circuit overload condition utilizes an arc chute to cool and extinguish the arc that occurs when the contacts become separated. The arc chute contains a plurality of metal arc plates supported by side plates which also assist in cooling and extinguishing the arc. The side plates are formed from a suspension of wollastonite fibers within a melamine resin matrix. The wollastonite provides good mechanical strength and temperature-resistance properties while the melamine provides a continuous source of arc-quenching gaseous molecular compounds.

Abstract: An industrial-rated molded case circuit breaker employs a pair of movable contact arms to interrupt circuit current through each phase of a multi-phase electrical power distribution circuit. A contact arm guide outboard the movable contact upon overcurrent conditions. A pair of protrusions formed on the abutting surfaces of the contact arms prevents the arms from distortion under the electrodynamic attraction generated during intense overcurrent conditions. A flexible arc gas exhaust-seal is arranged between the movable contacts and the line strap connectors to seal the circuit breaker enclosure while controllably exhausting the arc gases that occur upon such intense overcurrent conditions.

Abstract: A multi-component electric switch-circuit breaker module permits electric switches and circuit breakers to be field-installed within existing panelboard-switchboard enclosures. The module contains a pair of compartments that are accessed by separate doors. Electric switches or circuit breakers can be arranged within both compartments or an electric switch can be installed within one compartment with an electric circuit breaker installed within the other. The module is removably attached to the panelboard-switchboard interior by means of a bail handle arrangement. The module is removed from the assembly by unscrewing the bail handle and manually accessing the module. Spring-loaded connector clips allow for repeated connection with and disconnection from the systems power bus with minimum contact resistance.

Abstract: An electronic circuit interrupter digital display and keypad device includes a display to view circuit breaker settings combined with a keypad to select settings and values to be displayed. The display and keypad device connects to an electronic trip unit within the circuit interrupter by means of a tamper-free seal to prevent the circuit interrupter set points from being changed without authorization. Alternatively, a password-operated control switch provides a similar function.

Abstract: An integrated protection unit is an electronic trip circuit breaker which includes basic overcurrent protection facility along with selective electrical accessories. A molded plastic accessory access cover secured to the integrated protection unit cover protects the accessory components contained within the integrated protection unit cover from the environment. A combined overcurrent trip actuator and multiple accessory unit can be field-installed within the integrated protection unit. The combined actuator-accessory unit includes electronic control circuitry for the accessories along with mechanical trip and reset interface components. Additionally, a bell alarm signal unit can be incorporated within the trip actuator and multiple accessory unit enclosure.

Abstract: A digital circuit interrupter includes a microprocessor programmed for tailored overcurrent protection to power systems. A communication link permits the over-current set points to be selectively set within the microprocessor memory from a remote location. The over-current trip parameters are then derived by an algorithm which resides in the microprocessor memory.

Abstract: A molded case circuit breaker movable contact arm electrically connects with the circuit breaker load terminal without requiring a flexible electrical conducting braid. The contact arm is pivotally arranged within a contact arm support to which the load terminal lug is attached. The contact arm pivot pin is supported on a pair of parallel support posts extending from the contact arm support and a pair of bifurcated shunt plates are positioned on the pivot pin, one on each side of the contact arm to promote good electric transport between the contact arm and the support posts during short circuit conditions without interfering with the rotational movement of the contact arm.

Abstract: A compact current limiting circuit breaker with an electronic trip unit arranged within the circuit breaker cover and current transformers in the circuit breaker case incorporates reinforcement ribs in the cover to provide added strength. The cover also includes line terminal plugs that removably attach to the cover for preventing inadvertent access to the circuit breaker line terminals when the circuit breaker is energized. Protrusions formed on the bottom surface of the circuit breaker cover under the trip unit provide further strength while cooperating with flexible pads on the top of the current transformers to automatically compensate for manufacturing tolerances.

Abstract: An electric busway system consists of a plurality of planar bus bars insulated from each other and bolted together for good mechanical strength and for efficient thermal conductivity. The bus bars are additionally perforated to promote convective air current flow through the perforations when the bus bars are mounted in the horizontal plane.

Abstract: A combined arc gas controller-line terminal plug is used within molded case circuit breaker covers to direct the flow of arc gases that occur during intense overcurrent circuit interruption. The plugs simultaneously prevent access to the line terminal lugs while controlling the egress of the arc gases. Moreover, the plugs are removable for connection with and disconnection from an associated electrical power distribution system.

Abstract: A universal circuit breaker interlock arrangement allows two circuit breakers to be interlocked such that only one of the circuit breakers is on at one time. The circuit breakers can be interlocked, per se, or when used with an electrical motor operator or with a manual rotary operator. The slidably mounted interlock arrangement also allows interlock function between two electric switches as well as between an electric switch.

Abstract: A method and apparatus in a control system for an electromagnetic contactor for reducing multiple re-ignitions incorporates a regulated source of electrical power coupled to a contactor actuating coil through a controllable switch. The switch is used to regulate coil current to a desired value whereby opening time of the contactor can be determined within a defined range. Alternating current through tips of the contactor is monitored and each zero crossing of the current wave form is determined. The control system responds to a command to open the contactor tips by coordinating such opening with the zero crossings of the current wave form whereby the contact tips separate within a predetermined phase angle prior to a zero crossing. The system also includes apparatus for detecting a fault current of the alternating current in the contact tips and for inhibiting operation of the contact tips for a predetermined time interval in order to allow fuses to clear the fault prior to opening the contactor.

Abstract: A current limiting circuit interrupter consisting of a modular unit housed in an insulating case and provided with two fixed contact arms and two movable contact arms. The movable contact arms can be actuated automatically by means of a rod coupled to an operating mechanism as well as by means of an electromagnetic actuator. The operating mechanism includes a lever and a rotating bracket arranged to hold the movable contacts in an open condition when the electromagnet within the electromagnetic actuator is de-energized.