Abstract: A circuit breaker includes an electromechanical switch, a current sensor, a voltage sensor, and a processor. The electromechanical switch is serially connected between a line input terminal and a load output terminal of the circuit breaker, and configured to be placed in a switched-closed state or a switched-open state. The current sensor is configured to sense a magnitude of current flowing in a path between the line input and load output terminals and generate a current sense signal. The voltage sensor is configured to sense a magnitude of voltage at a point on the path between the line input and load output terminals and generate a voltage sense signal. The processor is configured to receive and process the current sense signal and the voltage sense signal to determine operational status information of the circuit breaker and determine power usage information of a load connected to the load output terminal.

Abstract: A direct-acting electromagnetic trip device including a housing, and a regulation mechanism, a linkage mechanism, an electromagnetic system and a trip mechanism which are arranged in the housing. The regulation mechanism is connected with the linkage mechanism, the linkage mechanism is connected with one end of an iron core of the electromagnetic system, and the linkage mechanism is connected with the trip mechanism at the same time. The regulation mechanism includes a rotary knob and a regulation rod, wherein the rotary knob is abutted against and engaged with the regulation rod, and the regulation rod is abutted against and engaged with the linkage mechanism. The electromagnetic system further includes an elastic element that pushes the iron core to allow the linkage mechanism to be abutted against the regulation rod and allow the rotary knob to be abutted against the regulation rod.

Abstract: A short-circuit protection action current adjusting method and a device thereof for a multi-pole electromagnetic release.

Abstract: Methods, apparatus, and systems are provided for a selectivity device for a circuit breaker. The invention includes a modular assembly adapted to be coupled to a load conductor assembly. The modular assembly includes a tripping plunger including a cam surface adapted to interact with a breaker tripping mechanism; an armature coupled to the tripping plunger; a yoke adapted to generate a magnetic field in response to an electric current in the load conductor assembly and disposed to apply a magnetic force proportionate to the electric current on the armature; and a spring assembly adapted to counter-balance the magnetic force up to a predefined tripping current in the load conductor assembly. Numerous additional aspects are disclosed.

Abstract: A circuit breaker includes a frame, at least one conductor supported by the frame, and a breaker mechanism supported by the frame and including a trip bar assembly that actuates the breaker mechanism. The circuit breaker also includes a magnetic armature assembly including an armature plate configured to move responsive to a current in the at least one conductor and an elongate link member (e.g., a rod) coupling the armature plate to the trip bar and having at least one flanged portion retained in at least one keyed slot in at least one of the armature plate and the trip bar assembly. The elongate link member may have a narrowed portion sized to allow passage of the link member through a narrowed portion of the at least one keyed slot to facilitate engagement of the at least one flanged portion in the at least one keyed slot.

Abstract: Various embodiments of a circuit breaker are described where a movable bridge connector is employed as part of the conductive path when the circuit breaker is in a closed configuration. When the circuit is opened, the connector is displaced from the two fixed contacts otherwise bridged by the connector. In one such embodiment, the circuit breaker utilizes the electromagnetic forces generated in response to the opening event to break the circuit.

Abstract: Embodiments disclose a trip blocking apparatus of a circuit breaker exhibiting no trip at OFF functionality. The trip blocking apparatus effectively blocks tripping of a trip bar when the circuit breaker is in the OFF configuration. The trip blocking apparatus has a trip blocking arm and a blocking lever. A first projection of the blocking lever is configured to contact a handle arm, and a second projection is configured to interfere with the trip blocking arm to block tripping of the trip bar responsive to handle arm motion. Actuator resetting and blocking apparatus and trip blocking assemblies and methods of operating the trip blocking assembly are provided, as are other aspects.

Abstract: A miniature circuit breaker having a pair of operable contacts in a main current path between a line terminal and load terminal, a trip mechanism for opening the contacts if an overcurrent condition occurs, and an electric motor to close the contacts via a contact closing mechanism. The trip mechanism includes a trigger mechanism and a contact opening mechanism, a current sensor arranged to detect current through the main current path, and a control unit. The trigger mechanism triggers the contact opening mechanism if a trip signal is produced. The control unit produces a trip signal to operate the trigger mechanism if it determines a short circuit condition occurs based on output of the current sensor; and the control unit is arranged to operate the electric motor to trigger the contact opening mechanism into opening the contacts independently of the trigger mechanism if it determines that an overload condition occurs.

Abstract: A circuit breaker comprises a latching plate rotatably coupled to a moveable plate, and tensile type latching springs, each latching spring having two ends fixed to the latching plate and the moveable plate, respectively. Time taken for a moveable contact to be lifted up from a contact time point between the moveable contact and a fixed contact may be shortened, and thus a time duration for which an accident current flows may be reduced. Accordingly, the amount of energy applied to the circuit breaker may be reduced, and a breaking function of the circuit breaker may be enhanced. Furthermore, since a contact pressure between the moveable contact and the fixed contact has a constant change, a reliability on a conductive state of the moveable contact and the fixed contact may be enhanced.

Abstract: An installation switching device having at least one pole current path comprises two stationary contact pieces; a moving contact bridge including two moving contact pieces forming a double-break pole with the two stationary contact pieces; a contact pressure spring exerting a pressure on the moving contact bridge in a closing direction of the moving contact bridge; a pusher configured to act on the moving contact bridge counter to the pressure of the contact pressure spring in an opening direction, the pusher including a slide and a striking pin disposed moveably relative to the moving contact bridge and to one another in a movement direction of the moving contact bridge; a switch latch having a latching point; an operating lever configured to act on the pusher; and an electromagnetic release having an impact armature.

Abstract: A switching device having a magnetic release includes a yoke having a U-shaped first section that includes a first limb having an opening in the form of a slot open towards a free end of the first limb, a second limb disposed parallel to the first limb, and a web connecting the first and second limbs. The switching device also includes a coil including a coil former, a coil winding and an armature disposed between the first and second limbs, wherein the coil is insertable into the slot towards the web and the armature extends through the slot. A restraint spring is connected at a free end of the armature and disposed outside the first limb.

Abstract: A divided armature for the trip mechanism of a circuit breaker especially useful for low trip current breakers allows for two independent adjustments: first of the magnetic air gap between the yoke and the armature and second of the clearance between the trip bar and the back plate of the armature. The divided armature allows the force of a return spring of the trip mechanism to be unchanged while adjusting the magnetic air gap to set the trip current point.

Abstract: A magnetic circuit includes a stationary iron core, a permanent magnet, and an armature, in a circular pattern. A contact mechanism spring separates the armature from the stationary iron core to open the magnetic circuit to switch a contact mechanism to a reset position. A coil on the magnetic circuit generates a magnetic flux in a direction same as that of the permanent magnet when an overload is detected and in an opposite direction when a predetermined time is elapsed after detecting the overload. A reset bar switches a movable stopper between an engaging position and a non-engaging position with the contact mechanism against a biasing force of the contact mechanism spring.

Abstract: Embodiments of an automatic single- or multi-pole circuit breaker for use in low-voltage applications are disclosed. The circuit breaker includes at least a first fixed contact this is coupled/uncoupled with a first moving contact. The moving contact is operatively connected to an operating mechanism that enables its displacement. The circuit breaker includes a kinematic tripping device driven by means of a first separating movement of the moving contact away from the fixed contact. The kinematic tripping device includes an operative member capable of tripping the operating mechanism, which in turn takes effect on the moving contact, thus determining a second rapid separating movement until the circuit breaker tripped position is reached.

Abstract: A user adjustment assembly for translating user-adjustable dial settings to tripping levels of an electronic trip unit includes a potentiometer and an adjustment button. The potentiometer is positioned inside a cover of the trip unit and includes a potentiometer button. The adjustment button is coupled to the potentiometer for mechanically adjusting it and includes an insulation disc for increasing resistance to electrostatic discharge, preventing contaminants from entering the printed wire assembly components, and preventing application of downward force to the potentiometer button. The insulation disc has a bottom surface that is dimensioned to be larger than the potentiometer button. The adjustment button includes one or more stops that trigger a fail safe operation mode where the tripping levels are automatically adjusted to higher or predetermined protective levels when the adjustment button is moved to those stop positions. Switch calibration is obviated and the simplified design reduces overall cost.

Abstract: A tripping device comprises a coil frame, a coil, a plunger, a spring, and an anti-shock device. The coil is fixedly coupled to the coil frame and has a cylindrical channel extending therethrough. The plunger is reciprocatingly received within the cylindrical channel and the spring is structured to bias the plunger within the cylindrical channel. The anti-shock device includes at least one of a number of anti-shock devices structured to eliminate movement of the coil relative to the coil frame and a number of anti-shock devices structured to eliminate movement of the plunger relative to the cylindrical channel. An under-voltage release mechanism comprises a mounting bracket, a tripping device, and an angled support. The mounting bracket includes a first portion and a second portion. The angled support is fixedly coupled to the mounting bracket between the first and second portions and is structured to prevent flexing of the mounting bracket.

Abstract: A trip unit having a current leading element, an anchor having an up and a down position, and an oscillator having a first position and a second position. The oscillator in the first position permits the anchor to move into the down position, and the oscillator in the second position blocks the anchor from moving into the down position. Additionally, a magnetic yoke surrounds the current leading element and the anchor. A magnetic flux flowing through the magnetic yoke moves the anchor into the down position. A magnetic yoke surrounding the current leading element and the oscillator provides a magnetic flux flowing through the magnetic yoke moves the oscillator into the first position, or into the second position.

Abstract: An instantaneous trip mechanism for a mould cased circuit breaker in a trip mechanism of a mould cased circuit breaker, the instantaneous trip mechanism capable of easily adjusting a trip current sensitivity for initiating an instantaneous trip operation and of fabricating a reliable mould cased circuit breaker by employing a simple construction for the adjusting unit and supporting a constant trip current sensitivity by products, the instantaneous trip mechanism for the mould cased circuit breaker comprising: a fixed electromagnet for generating a magnetic force which is changed according to a current flowing on a circuit; an armature disposed to face the fixed electromagnet and rotatable to a position for tripping the mould cased circuit breaker by the magnetic force from the fixed electromagnet when a great current exceeding a normal current flows on the circuit; a spring for elastically biasing the armature in a direction of being separated from the fixed electromagnet; an adjusting dial member having a c

Abstract: A circuit breaker configured to be remotely operated is disclosed. The circuit breaker includes a set of main contacts configured to connect between an electrical source and an electrical load, an operating mechanism in operable communication to open and close the main contacts, and a remotely operable drive system configured to open and close the main contacts separate from actuation of the operating mechanism. The drive system includes a motor responsive to first and second control signals, a primary drive responsive to the motor, and an opening spring responsive to the primary drive, the main contacts being responsive to the opening spring. In response to the first control signal, the primary drive moves to charge the opening spring, and in response to the second control signal and the main contacts being closed, the primary drive moves to allow the opening spring to discharge thereby resulting in the main contacts opening independent of the motor.

Abstract: A trip system for a circuit breaker having a support frame, a trip unit, a crossbar, and a trip bar, is disclosed. The trip unit is responsive to an electric current for generating a trip force, the crossbar is directly coupled to the trip unit and to the support frame, and the trip bar is directly coupled to the support frame. The electric current at the trip unit generates a trip force that acts upon the trip bar to trip the circuit breaker. The crossbar remains substantially stationary during the tripping action.

Abstract: A trip unit for a circuit breaker having a current carrying conductor that electrically communicates with a cable or a bus bar. The trip unit includes a current carrying strap, a magnet core, an armature and a magnetic barrier. The current carrying strap is adapted to be in electrical communication with the current carrying conductor. The magnet core is disposed at the current carrying strap. The armature is pivotally disposed in magnetic communication with the magnet core. The magnetic barrier is disposed to shield the armature from a magnetic flux generated in the current carrying conductor.

Abstract: A trip system for a circuit breaker having a calibration system is disclosed. The calibration system includes a retainer, a tripping member responsive to an electric current, an actuator retained by the retainer, a spring adjuster adjustably engaged with the actuator and the tripping member, and a bias spring disposed for biasing the actuator in a first direction. Movement of the spring adjuster absent movement of the actuator and the tripping member results in a change in the bias spring force and no change in the position of the tripping member, and movement of the tripping member absent movement of the spring adjuster results in a change in the position of the tripping member and no change in the bias spring force.

Abstract: An electromagnetic relay with adjustable tripping threshold for a low-voltage circuit breaker, comprising a magnetic circuit that has a fixed part,, which comprises a fixed element made of ferromagnetic material, a core, and at least one winding coil, and a moving part, which has a moving plate made of ferromagnetic material and arranged so as to face at least partially the fixed element with the coil interposed between the moving plate and the fixed element, the moving plate being functionally connected to means for adjusting the tripping threshold; its particularity consisting of the fact that the moving plate and/or the fixed element have a contoured body that allows, by acting on the adjustment means, to set the tripping threshold by simultaneously varying the gap between the moving plate and the fixed element and the magnetic coupling between the moving plate and the core.

Abstract: A circuit breaker trip unit includes a housing and a rotary plunger pivotally mounted within the housing. The rotary plunger has an on position and a tripped position. A portion of the rotary plunger is pivoted outside of the housing in the tripped position. A trip bar is pivotally mounted within the housing and includes a first tab latching the rotary plunger in the first position and releasing the rotary plunger from the first position. The trip bar also includes a second tab. A trip actuator includes a solenoid and a rotary trip lever engaging the second tab of the trip bar, in order to pivot the trip bar and release the rotary plunger from the on position. A spring biases the trip bar, in order that the first tab latches the rotary plunger in the on position. A pair of springs biases the rotary plunger to the tripped position.

Abstract: A magnetic trip unit for actuating a latching mechanism to trip a circuit breaker upon an overcurrent condition, the magnetic trip unit includes: a flux return component in electromagnetic communication with an electrically conductive strap; a tube disposed within the flux return component; a stator disposed at a first end of the tube and connected to the flux return component, the stator having a stator surface at one end; and a plunger slidably extending from a second end of the tube, the plunger comprises a plunger surface at one end facing the stator surface, the plunger further includes another end adapted to operably interact with the latching mechanism, the plunger is biased to a predetermined gap position.

Abstract: The magnetic trip device of a circuit breaker has a magnetic pole in which a magnetic field is generated by load current, and an armature assembly that includes: a bracket supported for pivotal movement relative to the magnetic pole; a spring biasing the bracket to a position spaced from the magnetic pole; an armature hinged on the bracket; and an adjusting screw for adjusting a gap between the armature and the magnetic pole for calibrating the trip device without affecting the spring bias, which can be separately and independently adjusted to select the load current at which the magnetic trip is initiated.

Abstract: An adjustable magnetic trip unit for a circuit breaker includes a torsion spring which applies a bias force to the plunger of a trip solenoid. The torsion spring is mounted on a driven bevel gear and wound by an adjustment knob coupled to a driving bevel gear to adjust the current at which the solenoid is activated. An indexer having peripheral flats which engage a seat in the circuit breaker housing provides a plurality of discrete positions of the adjustment knob. Depressing the adjustment knob against a second spring unseats the indexer for rotation of the adjustment knob between settings. In addition, a slide with an inclined surface bearing against the plunger and coupled to the driven bevel gear, provides simultaneous adjustment of plunger gap with adjustment of the torsion spring force to increase the range of adjustment.

Abstract: A release unit for a circuit breaker is equipped with a magnet yoke and an armature collaborating with it for actuating a release device, in which case a nonmagnetic weight element that increases the inertia of the armature is applied to the armature.

Abstract: A pair of spring mounted masses have sufficient inertia to remain stationary in response to a shock force applied to the housing of a trip assembly in a circuit breaker to block movement of the trip bar and thereby prevent a nuisance trip.

Abstract: A molded case circuit breaker that includes a double headed calibration screw. The calibration screw has a first and second end with identical convex tip surfaces and screw driver engagement surfaces. The convex tip surface is suitable for engaging a bi-metal thermal overload element. The screw driver engagement surface is suitable for applying a screw driver to adjust the calibration screw position in order to adjust the deflection of the bimetal and calibrate the thermal overload protection. At least one calibration screw planar surface allows for improved sealant injection to permanently fix the screw position and associated calibration setting following adjustment.

Abstract: A shock-resistant solenoid assembly includes a trip solenoid and an inertia lock, the inertia lock being operable to resist unintended engagement of a core of the trip solenoid with a trip plunger of a trip unit of a circuit breaker. The core is movable along a tripping path between a retracted position and an extended position, with the core engaging the trip plunger in the extended position. The inertia lock includes an inertia member and a latch. In response to shock loading, the inertia member interposes the latch into the tripping path to engage the core and resist the core from operatively engaging the tripping plunger under inappropriate conditions. The Abstract shall not be used for interpreting the scope of the Claims.

Abstract: A thermal overload relay includes an inversion operation mechanism that is driven by a releasing lever to open or close a contact. The inversion operation mechanism includes a movable plate supported at one end so as to be inverted, and a tension spring for driving the movable plate for inversion. The releasing lever presses a middle of a wire of the tension spring to drive the movable plate for inversion. A projection is formed in the middle of the wire of the tension spring to contact with the releasing lever. Thus, a stable inversion operation can be made regardless of the positioning of an adjustment dial.

Abstract: A parallel pole magnetohydraulic circuit breaker (10), having a single trip element (271) and a pair of trip mechanisms (101, 102), achieving an increased current carrying capacity with reduced nuisance trips. The tip mechanisms (101, 102) are contained within separate housings (14, 16), with electrical connections (30, 40) and multipole trip mechanism (101, 102) communicating through apertures in the common wall (14′). Preferably, the armature (260) of the trip element (271) acts on a single trip mechanism (101, 102), which multiplies the available force to trigger a trip of the other tip mechanism.

Abstract: A circuit interrupter including a housing, separable main contacts disposed in the housing, and an operating mechanism disposed in the housing and interconnected with the contacts. A trip mechanism is disposed in the housing and has an automatic trip assembly that generates a tripping operation. The automatic trip assembly includes a magnetic yoke, an armature, and a plurality of abutment members. The magnetic yoke has pivot supports providing for a rotatable disposition of a head portion of the armature. The assembly also includes a biasing member having a first portion and a second portion, the first portion abutted against a selected one of the plurality of abutment members, the second portion abutted against the armature and applying a force to the armature in a direction to normally rotationally displace a bottom portion of the armature away from the magnetic yoke, wherein selecting a different one of the plurality of abutment members to be the selected one causes the force to vary.

Abstract: An adjustable solenoid having an enclosure containing a winding through which a current is passed. The winding defines an area and a plunger is positioned at one end of the area with a mechanical biasing mechanism for providing a biasing force to the plunger, the mechanical biasing mechanism is secured to the plunger at one end and a support at the other end. A stator having a first threaded portion engaged within a threaded opening of the enclosure causes the stator to travel between a first position and a second position as a rotational force is applied to the stator.

Abstract: The present invention provides an armature assembly for adjusting the magnetic calibration of a tripping mechanism in a circuit breaker includes a bracket having a channel defined by a pair of legs and a bight with opposing sides. A first tab and a second tab are fixedly connected to opposing sides of the bight. The first and second tabs are positioned parallel to one another and perpendicular to the opposing sides of the bight. The first and second tabs have a respective first and second hole that are threaded. A first pin rotatably connects to the tripping mechanism within the interior of the circuit breaker. The first pin is affixed across the legs of the channel. An adjustment screw has an elongated body with a top portion on one end and at the opposing end a bottom portion. The adjustment screw has a plurality of screw threads defining an exterior side wall of the elongated body along the bottom portion. The plurality of screw threads configured to releasably engage the threaded fastener component.

Abstract: An improved rating plug housing is presented for use with circuit breakers having electronic trip units. The housing (10) for the rating plug has a series of protruding tabs (14) on the bottom of the housing (10). A trip unit housing (50) forms part of a circuit breaker housing. Trip unit housing (50) includes a recess (52) for receiving the trip unit housing (10). Recess (52) has a series of castellations (54) on the bottom of the recess (52). If a rating plug is appropriate for a given trip unit, the pattern of tabs (14) and castellations (54) will not interfere, and insertion will be permitted. If a rating plug is not appropriate for a given trip unit, the pattern of tabs (14) and castellations (54) will interfere, and insertion will not be permitted. Tabs (14) or projections (53) may be removed from housing (10) or recess (52) using a hand-held tool.

Abstract: An adjusting ring includes a surface which is matched to the pitch of the winding wire. This adjusting ring is used in a device having a coil winding. As such, the coil winding can be positioned in its axial direction.

Abstract: A shock resistant under-voltage release mechanism for a circuit breaker includes a magnetic tripping device resiliently mounted onto a mounting bracket with one or more resilient mounts. The magnetic tripping device includes a plunger that selectively engages a trip button of the circuit breaker when the voltage supplied to a coil of the magnetic tripping device drops below a given preset limit voltage. The resilient mounts each include first and second flanges, with a hub extending between the first and second flanges. The resilient mount is mounted on the mounting bracket of the under-voltage release mechanism such that the hub is disposed against a mounting hole formed in the mounting bracket, and the first and second flanges are disposed against the opposite faces of the mounting bracket. A fastener is slidingly received through an opening formed in each resilient mount and is attached onto an attachment hole formed on a coil frame of the magnetic tripping device.

Abstract: An adjustable thermal-magnetic trip unit for a molded case circuit breaker 10 is disclosed, with the circuit breaker 10 including a housing 12 having an operating mechanism 40 including an intermediate latch 52, a line terminal 18, a load terminal 16 and a cover 20. The adjustable thermal-magnetic trip unit includes a magnetic yoke 66 mounted in the housing 12, and a bimetal member mounted in the magnetic yoke 66, with the bimetal member having a fixed end and a movable end. The fixed end is coupled to a load bus 61 of the load terminal 16, and the movable end is coupled to a movable contact of the operating mechanism 40. The trip unit 610 also includes a horizontal trip bar rotatably mounted in the housing 12, with the trip bar 54 having an actuating arm gapped from the movable end of the bimetal member and with the actuating arm aligned to selectively engage the movable end of the bimetal member.

Abstract: A flux transfer shunt trip actuator has an elongated seat member extending between the legs of a U-shaped magnetically permeable frame member. A plunger is magnetically latched against the seat formed by the seat member in a retracted position by permanent magnets positioned adjacent the seat. The field generated by permanent magnets produces a latching force which exceeds a bias force generated by a helical compression spring extending along the elongated seat member and biasing the plunger toward an actuated position spaced from the seat. A coil surrounding the elongated seat member and the spring, generates an electromagnetic field when energized which bucks the permanent magnet field so that the plunger is driven to the actuated position by the spring. Preload on the spring is adjusted by an adjusting member positioned along a threaded shaft coaxial with the spring and extending from the bight of the U-shaped frame in the opposite direction from the pair of legs of the frame.

Abstract: An adjustable magnetic trip unit for a circuit breaker (1) is equipped with a magnet yoke (16), an armature element (18) that works therewith to actuate a trip shaft (14), and an adjusting bar (23) that can be tilted about the axis (15) of the trip shaft (14) for adjusting the distance (L) between the magnet yoke (16) and the armature element (18). This magnetic trip unit can be used in a circuit breaker (1) having a plurality of breaker cassettes (30) arranged adjacent to one another wherein the adjusting bar (23) extends parallel to the axis (15) of the tripping shaft (14) and on which are arranged a plurality of adjusting arms (24) corresponding to the number of breaker cassettes (30).

Abstract: A thermal trip unit within a multi-pole circuit breaker includes a bimetal element having an off-set end to provide cam function during the calibration of the bimetal element. A calibration screw is threadingly engaged within the bimetal element and is adjusted at various calibration levels by means of a step motor driver element.

Abstract: A circuit breaker includes an upper rail mounting device defined by a line terminal having a pair of spaced-apart jaws. A bimetal is adjusted by means of a calibration screw. An aperture is provided in an upper sidewall portion of a base of the circuit breaker for access to the calibration screw by a calibration device. The aperture is positioned so that the calibration device must pass through the jaws of the upper rail mounting device. This ensures that the calibration screw can only be operated when the circuit breaker is disconnected from an electrical supply.

Abstract: In an exemplary embodiment of the invention, a calibration arrangement and process for use in a circuit protective device are presented. An exemplary calibration assembly for use in the calibration process of the present invention includes a split clamp arm having a first opening for receiving and holding a calibration pin and a second opening for receiving an actuator key. A portion of the split clamp arm is divided into a first arm and a second arm by a channel which extends from a first end of the split clamp arm through the first opening and communicates with the second opening. The split clamp arm is opened by inserting the actuator key through the second opening and because of the preferred oblong or rectangular shape of the second opening of the split clamp arm, rotation of the actuator key therein forces the members forming the first opening of the split clamp arm apart from one another.

Abstract: A mid-trip stop circuit breaker, having a handle, adapted for displacement about an axis of rotation between a first position and a second position, the handle being linked to a member whose position corresponds to a rotation position of the handle, a spring urging the handle toward the second position; a stop surface, displaceably supported in relation to the axis of rotation, the stop surface being selectively disposed along a path of the member at a middle position of a transition path from the first position to the second position, and being adapted to engage the member and counter a force of the spring, to retain the handle in the middle position of the transition path, such that a sufficient manual force applied to the handle when retained at the middle position of the transition path will displace the stop surface, allowing the handle to achieve the second position, while in an absence of the sufficient manual force and under influence of the spring alone, the stop surface impedes displacement of the h

Abstract: The trip bar is sub-divided into a first actuating part associated to the trip rod of the actuator and a second actuating part operating in conjunction with the indicating device. A mechanical coupling link is arranged between the two actuating parts being adjustable between a coupled position and a disengaged position. An operating lever performs locking of the second actuating part in the active position to keep the fault information on the indicating device, whereas the first actuating part returns automatically to the inactive position when said mechanical link is in the disengaged position.

Abstract: The trip device comprises a magnetic circuit having a first and second fixed parts, a movable element and an adjustment device. The adjustment device comprises a shunt and an air gap arranged between the first and second fixed parts branched off with respect to the mobile element. The tripping threshold of the trip device is modified by varying the air gap distance between the shunt and the second fixed part. In a circuit breaker, the mobile element acts on an opening mechanism and an adjustment part acts on the adjustment device making the air gap distance vary. A sensor associated to the magnetic circuit supplies a measurement signal to a processing unit.

Abstract: A solenoid type magnetic trip assembly for a molded case circuit breaker includes an armature biased against an adjustable stop by a tension spring to set the initial gap for the magnetic trip, so that the spring bias remains constant for the full range of the initial gap. The armature includes an elongated armature element mounted by a frame to slide longitudinally along a pair of guide rails. The frame defines a trip surface axially aligned with the elongated armature element which engages a trip arm on a trip bar to trip the circuit breaker in response to a predetermined level of overcurrent. A bimetal providing a thermal trip function is cantilevered from a support spaced from the trip bar by the armature, but has a terminal portion at the free end projecting toward the trip bar and through which the elongated armature element of the armature extends.

Abstract: A circuit breaker has a shock absorber to prevent nuisance tripping which results from shock generated during ON to OFF operation of the circuit breaker. The shock is primarily caused by a snap action which occurs within the operating mechanism of the circuit breaker when the handle is moved from the ON to OFF position. The snap action results from the circuit breaker employing, as part of the operating mechanism, a toggle mechanism within an over center tension spring as a means for imparting motion in the operating mechanism. By strategically positioning the shock absorber for engagement with the operating mechanism when the circuit breaker is in the OFF position, the shock may be effectively absorbed thereby preventing the undesirable nuisance tripping.