Abstract: An electronic circuit for use on a contactor is disclosed. The electronic circuit may be encased in a housing and mounted to a coil cover on the front of a contactor for applying control power to the coil for a selected time period to enable the contactor to change its state and be held in the changed state. Thereafter, the electronic circuit disconnects the supply to the coil thereby preventing coil burn out. The control power is only applied after initiation of an input signal from a switch and after a controller in the electronic circuit has slept for a first predetermined period of time so as not to register any bounce from the input signal. The electronic circuit may include an auxiliary contact status check for providing error free activation of the mechanically held contactor when changing state of the contactor. A contactor employing the electronic circuit of the present invention and a method of using the electronic circuit on a contactor are further disclosed.

Abstract: A field configurable contactor is disclosed. The contactor preferably includes a plurality of spaces adapted to receive any number, up to its limit, of contact modules. Each contact module preferably includes a pair of contacts and a spring biased cam follower which opens and closes the contact pair when a cam profile of the contactor moves according to energization or de-energization of the contactor. The contact module can be either “normally open” or “normally closed” depending on its initial placement onto the contactor relative to the cam profile. A latch assembly in the contactor may hold the contactor mechanically during de-energization.

Abstract: An electronic circuit for use on a contactor is disclosed. The electronic circuit may be encased in a housing and mounted to a coil cover on the front of a contactor for applying control power to the coil for a selected time period to enable the contactor to change its state and be held in the changed state. Thereafter, the electronic circuit disconnects the supply to the coil thereby preventing coil burn out. The control power is only applied after initiation of an input signal from a switch and after a controller in the electronic circuit has slept for a first predetermined period of time so as not to register any bounce from the input signal. The electronic circuit may include an auxiliary contact status check for providing error free activation of the mechanically held contactor when changing state of the contactor. A contactor employing the electronic circuit of the present invention and a method of using the electronic circuit on a contactor are further disclosed.

Abstract: Low voltage electric switchgear equipment includes a central processor unit electrically interconnected with electronic main and branch circuit interrupters within the same enclosure and used within a multi-phase power distribution circuit. A terminal connector block is connected by cable with each of the electronic trip units within the branch circuit interrupters to provide communications between the branch circuit interrupters and the main circuit interrupter for continuously updating the status of the branch circuit interrupters and their associated electrical equipment. Strain relief is provided to the cable connecting between the terminal connector block and the branch circuit interrupter to prevent damage to the electrical components within the electronic trip unit that are internally connected with the cable.

Abstract: Molded plastic bus covers are attached to the ends of a pair of molded case circuit breakers to isolate the circuit breakers from an electrical enclosure as well as to isolate between the circuit breakers themselves when connected within the enclosure in a double-branch configuration. Molded plastic lug covers are attached to the opposite ends of a molded case circuit breaker when the circuit breaker lugs are connected to power distribution cables to electrically isolate the power cables and the circuit breaker lugs.

Abstract: An electronic trip molded case circuit breaker includes components that are designed for high speed robotic assembly. A unitary trip-to-test button is down-loaded within the circuit breaker housing for automatic alignment with the circuit breaker operating mechanism during the circuit breaker assembly process. A unitary auxiliary switch interface unit is also down-loaded within the housing for automatic alignment with the operating mechanism during the assembly process.

Abstract: A molded case circuit breaker having a pair of movable contact arms arranged within each pole of a multi-pole arrangement utilizes a shunt clip between the movable contact arms to insure electrical continuity between the contact arms and the contact arm support base. The movable contact arms and the support base are both accurately positioned within the circuit breaker case by means of an interference-fit between the outside edges of the support base and the interior sidewall surfaces of the circuit breaker case.

Abstract: An electronic trip molded case circuit breaker includes components that are designed for high speed robotic assembly. A unitary trip-to-test button is down-loaded within the circuit breaker housing for automatic alignment with the circuit breaker operating mechanism during the circuit breaker assembly process. A unitary auxiliary switch interface unit is also down-loaded within the housing for automatic alignment with the operating mechanism during the assembly process.

Abstract: An operating mechanism assembly used within molded case circuit breakers employing electronic trip units interconnects the operating mechanism with the circuit breaker movable contact arms by means of a slotted-cam arrangement. The slotted-cam optimizes the manual closing of the movable contact arms by controllably over-centering the circuit breaker operating mechanism springs.

Abstract: A molded case circuit breaker of the type using electrodynamic repulsion to separate the circuit breaker contacts under intense overcurrent conditions also includes an arc chute arrangement for cooling and quenching the arc that occurs during such contact separation. A plastic insert added to the interior of the circuit breaker cover multi-functionally retains the arc chute within the circuit breaker case while providing clearance for the circuit breaker operating handle shutter.

Abstract: An operating handle assembly for molded case circuit interrupters is robotically assembled to the circuit breaker operating mechanism without requiring any auxiliary fastening device. A visual access slot in the circuit breaker cover allows the condition of the circuit breaker contacts to be visually ascertained by use of colored indicia carried by the operating handle skirt. A slidably mounted handle shutter cooperates with the operating handle to prevent egress of arc exhaust gases in the event the circuit breaker contacts are closed or opened during overcurrent conditions when the circuit breaker is installed within an industrial power distribution circuit.

Abstract: An electronic circuit interrupter includes an electronic trip circuit contained within a circuit interrupter enclosure along with an externally accessible rating plug for setting the ampere rating. The rating plug includes keying tabs that fit within corresponding keying slots formed on the top surface of the electronic circuit interrupter enclosure. Interlock is provided between the rating plug and the electric panelboard which includes a plurality of electronic circuit interrupters connected within an industrial power system. Tabs formed on the side walls of the rating plug are trapped under the panelboard face plate to prevent removal of the rating plug without first removing the panelboard face plate.

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.