Abstract: A method for assembling an arc fault circuit breaker such that electrical interconnections, i.e., electrical connections between compartments, are made without disassembling any previously assembled compartment. The arc fault circuit breaker comprises housings having compartments within. Electrically connected components having interconnecting components, i.e., components which provide electrical interconnections between compartments, are disposed within the compartments. The housings are assembled together to enclose the compartments. Interconnecting components within an enclosed compartment extend through openings in the housings to provide electrical interconnections to the next compartment to be assembled. Therefore, no disassembly of the enclosed compartment is necessary to make the interconnections.

Abstract: An arc fault circuit breaker assembled such that electrical interconnections, i.e., electrical connections between compartments, are made without disassembling any previously assembled compartment. The arc fault circuit breaker comprises housings having compartments within. Electrically connected components having interconnecting components, i.e., components which provide electrical interconnections between compartments, are disposed within the compartments. The housings are assembled together to enclose the compartments. Interconnecting components within an enclosed compartment extend through openings in the housings to provide electrical interconnections to the next compartment to be assembled. Therefore, no disassembly of the enclosed compartment is necessary to make the interconnections.

Abstract: A stab assembly (41) in which a spring clip (24) and a conductor member (16) define a pair of engagement surfaces for engaging a stab blade (12). The conductor member (16) has an opening (34) to allow for the insertion of an extended surface of the spring clip (24). Once in position, the spring clip (24) and conductor member (16) are frictionally engaged and define a channel (126) that will accept and hold a stab blade (12). The stab assembly (14) is retained within a molded case circuit breaker (10) and provides electrical contact between a bus bar and the circuit breaker.

Abstract: An arcing fault detection circuit breaker (10) with strain relieved electrical tap comprises an electronic trip unit (68) to detect arcing from line (30) to neutral (80). Arcing is detected by measuring the voltage drop across a bimetal (32). Voltage drop across the bimetal (32) is sensed by a twisted pair conductor (62), which is electrically connected across the bimetal (32). The bimetal (32) has a fixed end (34) and an opposing free end (54), which is free to move. A strain relief element in the form of stepped eyelet (92) is used to affix one conductor (64) of the twisted pair conductor (62) to the bimetal (32) so that the conductor (64) remains affixed to the free end (54) of the bimetal (32) during movement of the bimetal (32).

Abstract: An arc fault circuit breaker (10) conducting an electric current to a protected load is presented. The circuit breaker (10) has a first (mechanical) compartment (24) and a second (electrical) compartment (62). A bimetal resistor (50) is disposed within the first compartment (24) and conducts the current therethrough. The bimetal resistor (50) has a stud (56) extending into the second compartment (62). A single sense line (60) is electrically connected to the bimetal resistor (50) and routed into the second compartment (62). The sense line (60) and said stud (56) conduct a voltage signal indicative of arcing of the current. A circuit board (84) is disposed within the second compartment (62) and is connected to the sense line (60) and stud (56) within the second compartment (62) to process the voltage signal. The circuit board (84) has a first conductive path (104) electrically connected to the stud (56), and a second conductive path (106) electrically connected to the sense line (60).

Abstract: A circuit breaker including a housing having a window, a line terminal and a load terminal, and a circuit trip assembly. The circuit trip assembly includes a rotatable cradle, a moveable armature latch and a pivotable trip support including a trip indicator. Upon the occurrence of a tripping condition in the circuit breaker, the trip indicator moves from a first position where it is not visible through the window to a second position where it is visible through the window.

Abstract: A visible trip indication arrangement for a circuit breaker. The visible trip indication arrangement comprises a viewing window forming a part of the breaker housing, the viewing window including indicia thereon that is readily or enhancedly visible when the circuit breaker has been tripped and essentially not visible when the circuit breaker is operating by way of a trip indicator that moves under and aligns with the viewing window when the circuit breaker is in the tripped condition. The trip indicator having a brightly colored surface, causes the indicia on the viewing window to be readily visible by way of the reflected light off a surface thereof.

Abstract: A collapsible contact arm drive link arrangement for a circuit breaker operating mechanism has a pair of upper links for receiving the circuit breaker operating mechanism and a lower link for receiving a circuit breaker contact arm carrier at one end. Intermediate the upper links and the lower link, a scissors link, which is connected with the upper links and lower link, allows the lower link to move from a first position (e.g., closed) to a second position (e.g., tripped). The movement occurs upon the application of a force on the lower link in excess of a predetermined force that is applied to the upper links.

Abstract: A molded case circuit breaker base is configured to receive pole modules that include the circuit breaker components for mutipole operation. The base is configured to receive the bottom edges of the module enclosures in press-fit relation. A complementary molded case circuit breaker cover attaches to the top of the modules to complete the multipole circuit breaker enclosure.

Abstract: An air circuit breaker movable contact arm assembly is presented. The movable contact arm assembly comprises an electrically-conductive support having at least one slot formed therein to receive a first end of the movable contact arm. The movable contact arm comprises first and second sides which face side walls of the electrically-conductive support within the slot. A spring washer is disposed at the first end of the movable contact arm and loads the second side of the movable contact arm against one side wall of the electrically-conductive support to form a variably conducting joint therebetween. By using a spring washer, the movable contact arm pivotally engages the other facing side wall of the electrically-conductive support to provide a variable pivot point. The variable pivot point of the contact arm assembly permits an additional degree of freedom allowing the movable contact arm to rotate about a separate, variable pivot point.

Abstract: A circuit interrupter employing an electronic trip unit utilizes a current transformer assembly containing both air and metal cores on a common load strap for providing sensing current to the electronic trip unit along with supplying operating power to the trip unit electronic components. A two-part plastic housing provides support for the metal core and the sensing coil while further providing thermal transfer of heat generated within the transformer secondary windings out to the load strap.

Abstract: A circuit breaker contact position indicator is mounted on the same support platform as the circuit breaker electronic trip unit and contains a micro-switch to provide indication to the trip unit of the status of the circuit breaker contacts. The switch interacts with the circuit breaker operating mechanism crossbar cam by means of a spring-loaded paddle attached to the trip unit support platform.

Abstract: An arcing fault detecting module is attached to a circuit breaker employing a thermal-magnetic trip unit to separate the circuit breaker contacts upon occurrence of an arcing fault. The arcing fault module contains a logic circuit and a current transformer for detecting the arcing fault and actuating a trip solenoid to articulate the circuit breaker operating mechanism and separate the circuit breaker contacts.

Abstract: An integrated circuit breaker is provided with shunt trip capability along with automatic overcurrent protection through the circuit breaker trip unit and shunt trip module. The shunt trip module further provides auxiliary power to the trip unit and allows the trip unit microprocessor to report and record the shunt trip operation. The trip unit communicates with the circuit breaker operating mechanism to determine the ON-OFF status of the circuit breaker contacts.

Abstract: A lockout solenoid is connected with the circuit breaker accessory shunt trip in a high ampere rated circuit breaker and interacts with the circuit breaker accessory lever to prevent the closing of the circuit breaker contacts until the shunt trip activation voltage signal is turned off. The circuit breaker accessory lever interlocks the circuit breaker closing button to prevent closing the circuit breaker contacts until such shunt trip activation voltage signal is turned off.

Abstract: A modular current transformer containing both air and metal cores on a common load strap provides sensing current to the electronic trip unit within the circuit interrupter along with supplying operating power to the trip unit components. The current sensing coil is arranged concentricity within the transformer core while the power generating coil is arranged concentricity outside the core.

Abstract: Each pole of a multi-pole circuit breaker is equipped to individually separate the circuit breaker contacts within each pole upon overcurrent occurrence. A digital processor within the circuit breaker trip unit determines the occurrence of zero current crossing of phase current within the individual poles and initiates contact separation at zero current values.

Abstract: The circuit breaker interlock arrangement of the invention utilizes a pair of detector assemblies, one mounted on the rear surface of each one of a pair of first and second adjoining circuit breakers and interconnected by means of an elongated rod. The operating mechanism tripping plunger rod in the first circuit breaker trips the associated first circuit breaker operating mechanism to open the first circuit breaker contacts when an attempt is made to close the first circuit breaker contacts when the second circuit breaker contacts in the second circuit breaker are already closed, and vice versa.

Abstract: A circuit breaker shunt trip accessory unit contains a solenoid driven plunger that interacts with the circuit breaker operating mechanism to interrupt circuit current by means of an external signal. A mechanical override feature insures operation of a blocked solenoid plunger once the source of the blocking is removed.