Abstract:
A microprocessor-based circuit breaker includes a chip that defines the current rating or ground fault current for the breaker. Thus, the maximum current rating and/or ground fault current can be set after manufacture using the chip that is electrically connected to the microprocessor. The breaker includes mechanical components that trip to disconnect the load terminal from the line input. The mechanical components include a floating breaker arm, trigger and tripper lever that cooperate to control the tripping of the breaker. A spring between the breaker arm and trigger, together with cam surfaces defined in the breaker switch cooperate to form a floating linkage to control the position of the breaker arm during on/off activation and current fault conditions. The circuit breaker also includes multiple indicia to provide a visual indication of the type of fault condition sensed by the breaker.

Description:
[0001]     This application is a divisional application of U.S. application Ser. No. 10/143,452, filed on May 10, 2002. 
     
    
     BACKGROUND OF THE INVENTION  
     TECHNICAL FIELD  
       [0002]     The present invention relates to circuit breakers. In specific embodiments, the invention concerns microprocessor-controlled circuit breakers.  
         [0003]     Electrical trip systems are designed to respond to a fault in an electrical supply system by disconnecting the supply from the electrical load. One common trip system uses an electromagnet to trip a breaker in response to a short circuit or an electrical overload. In this type of device, the electromagnet generates a magnetic field when current is flowing through the device. When the current exceeds a threshold level, the magnetic field trips a mechanism that causes the breaker contacts to move apart or disconnect, thereby “breaking” the circuit path.  
         [0004]     As the electrical system demands have increased, the level of sophistication of circuit breakers has also increased. Processor-based tripping systems have been developed to provide more accurate and flexible circuit breaking capabilities. These microprocessor-based systems permit programming of many features of the breaker, such as current rating, calibration, and fault conditions, as well as storage of pre-fault data.  
         [0005]     The present invention contemplates an electrical trip system or circuit breaker that provides multiple indicia of fault conditions. According to one protocol of the inventive circuit breaker, a short-circuit condition is signified by a red indicator in conjunction with movement of the breaker switch to a neutral position. An overload or phase failure condition is signified by a black indicator in conjunction with movement of the breaker switch to a neutral position. A ground fault condition yields a yellow indicator in conjunction with movement of the breaker switch to a neutral position. Under normal conditions, the indicator is black with the breaker switch in its “ON” position.  
         [0006]     In one aspect of the invention, the current rating of the circuit breaker is determined by a user-selectable resistor chip that can be plugged into the processor for the circuit breaker. Likewise, the ground fault current can be established by a separate user-selectable resistor chip that is connected to the breaker processor.  
         [0007]     In a further feature of the invention, the trip mechanism includes a floating breaker arm disposed between the breaker switch and a trigger. The trigger is held in its armed position by a tripping lever and is spring connected to the floating breaker arm. The breaker arm is electrically connected to the line input and includes a breaker contact that is normally in electrical contact with a load terminal. The breaker arm can be moved to break this electrical contact by deliberate movement of the breaker switch without disturbing the position of the trigger. Alternatively, the breaker arm can be moved to break the electrical contact with the load terminal by release of the trigger.  
         [0008]     In one aspect of the breaker function, the magnetic lever and armature arrangement is disposed between the line input and the floating breaker arm. The magnetic lever is operable to detect short circuit condition and to actuate the tripping lever to activate the trigger.  
         [0009]     In a further feature, the circuit breaker includes a coil actuator that can actuate the tripping lever in a ground fault or an over-current condition. The tripping lever can thus be alternatively actuated by the coil actuator or the magnetic lever.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]      FIG. 1  is a side cutaway view of a circuit breaker in accordance with one embodiment of the invention, with the breaker in its normal operative configuration.  
         [0011]      FIG. 2  is an enlarged side perspective view of a floating breaker arm included in the circuit breaker shown in  FIG. 1 .  
         [0012]      FIG. 3  is an enlarged side perspective view of a breaker switch included in the circuit breaker shown in  FIG. 1 .  
         [0013]      FIG. 4  is a cutaway partial cross-sectional view of the breaker switch shown in  FIG. 3 .  
         [0014]      FIG. 5  is an enlarged side perspective view of a tripping lever included in the circuit breaker shown in  FIG. 1 .  
         [0015]      FIG. 6  is an enlarged side perspective view of a magnetic lever included in the circuit breaker shown in  FIG. 1 .  
         [0016]      FIG. 7  is an enlarged side perspective view of a magnetic armature included in the circuit breaker shown in  FIG. 1 .  
         [0017]      FIG. 8  is an enlarged side view of a torsion spring used with the magnetic lever and armature shown in  FIGS. 6 and 7 .  
         [0018]      FIG. 9  is an enlarged side perspective view of an arc separator plate used with the floating breaker arm shown in  FIG. 2 .  
         [0019]      FIG. 10  is an exploded component view of a fault indicator assembly included in teh circuit breaker shown in  FIG. 1 .  
         [0020]      FIG. 11  is an exploded component view of a coil actuator assembly included in the circuit breaker shown in  FIG. 1 .  
         [0021]      FIG. 12  is an exploded component view of a chip assembly included in the circuit breaker shown in  FIG. 1 .  
         [0022]      FIG. 13  is a side cutaway view of the circuit breaker shown in  FIG. 1  with the breaker switch in its “off” position.  
         [0023]      FIG. 14  is a side cutaway view of the circuit breaker shown in  FIG. 1  in its configuration responding to a short circuit condition.  
         [0024]      FIG. 15  is a side cutaway view of the circuit breaker shown in  FIG. 1  in its configuration responding to an over-circuit condition.  
         [0025]      FIG. 16  is an enlarged side cutaway view of the mechanical breaker components in the normal or “on” configuration.  
         [0026]      FIG. 17  is an enlarged side cutaway view of the mechanical breaker components in the “off” configuration.  
         [0027]      FIG. 18  is an enlarged side cutaway view of the mechanical breaker components in a trigger condition.  
         [0028]      FIG. 19  is a side cutaway view of a circuit breaker in an alternative embodiment of the invention shown in a ground fault condition.  
     
    
     DETAILED DESCRIPTION  
       [0029]     For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and described in the following written specification. It is understood that no limitation to the scope of the invention is thereby intended. It is further understood that the present invention includes any alterations and modifications to the illustrated embodiments and includes further applications of the principles of the invention as would normally occur to one skilled in the art to which this invention pertains.  
         [0030]     In one embodiment of the invention, a circuit breaker  10  is provided that includes a housing  11  containing the various mechanical and electrical components of the breaker. A line terminal  13  is provided for connection to a line load, while a load terminal  14  permits electrical connection to a consumer load. A processor  16 , which is preferably a microprocessor, is connected between the line and load terminals to monitor the condition of the electrical current flowing through the circuit breaker  10 .  
         [0031]     It is understood that the processor  16  can be of conventional design and that in the typical case the processor is not directly connected to the line input due to the high voltage and current of that input. Instead, the processor  16  relies upon signals from various sensors, such as current or voltage sensors, to accept a reduced voltage/current signal indicative of the electrical condition of the current flowing through the breaker. In the illustrated embodiment, a current transformer  17  can be provided to produce a low magnitude signal indicative of the breaker current. This signal can be provided to the processor  16  as well as to other components of the circuit breaker  10  as discussed herein.  
         [0032]     The mechanical breaker components of the circuit breaker  10  include a stationary contact  21  that is electrically connected to the load terminal  13 . A floating breaker arm  22  includes a moving contact  23  that is connected to an internal conductor or wire  19 , which is preferably a shielded copper wire. This wire is connected to the line terminal  14  to pass electricity to the load terminal when the moving contact  23  engages the stationary contact  21 . In the normal operating condition, the two contacts are engaged so that electricity flows freely through the circuit breaker  10 . When an abnormal electrical condition arises, the flow of electricity is interrupted by disengaging the moving contact  23  from the stationary contact  21 , in a manner that is well known in the art. In one embodiment, the conductor wire  19  can include an unshielded portion  24  that is connected to the floating breaker arm  22  in a manner described herein.  
         [0033]     More specifically, the breaker arm  22  can be constructed as shown in  FIG. 2 . The breaker arm  22  is preferably formed from a sheet of conductive material, such as tin-plated copper. The arm  22  is bent into a generally U-shape to define a top wall  52  and opposite side walls  55 . The moveable contact  23  is mounted to the top wall  52 . One of the side walls  55  can include a tab  60  that can be crimped around the end of conductor wire  19  to provide an electrical interface to the breaker arm  22 .  
         [0034]     For purposes that will be explained in more detail below, the breaker arm  22  defines a spring slot  53  in the top plate  52  and an aperture  57  in one of the side walls  55 . The U-shape formed by the opposite side walls  55  define a trigger channel  61  for receiving a trigger  30  therein. Each of the side walls  55  includes a fulcrum tip  59  and defines a cam edge  55   a,  as shown in  FIG. 2 . Moreover, on of the side walls forms a trigger contact  56 , again for purposes more fully explained herein.  
         [0035]     One of the side walls  55  defines an aperture  57  that is used to support an arc separator plate  32 . As shown in  FIG. 9 , the separator plate  32  forms a hook  85  that is received within the aperture  57 . As shown in  FIG. 1 , the arc separator plate  32  slides within a channel  33  formed in the housing  11 .  
         [0036]     The circuit breaker  10  also includes a breaker switch  25  that can be used to deliberately move the breaker from its “on” or active, to its “off” or disconnected state. In addition, the position of the switch serves as an indicator of the type of electrical fault sensed by the breaker. The switch  25  is pivotably mounted within the housing  11  by a pivot mount  27 . As shown in more detail in  FIGS. 3 and 4 , the breaker switch includes a generally U-shaped pivot body  26  that is configured to straddle both the floating breaker arm  22  and the trigger  30 . The pivot body, thus, includes opposite walls  62  that define a channel  63 . At least one, and preferably both, of the opposite walls  62  defines a curved cam edge  64  for purposes explained below.  
         [0037]     The switch is sectioned in  FIG. 4  to illustrate interior features of the opposite walls  62 . In particular, each wall defines a cam recess  65  and a pivot recess  66 . The two recesses are configured to receive the fulcrum tips  59  of the floating breaker arm  22  and allow the tips, and consequently the arm, to pivot or cam freely within the switch  25 . Preferably, the side walls  55  of the breaker arm  22  are separated by a width that permits a tight, but movable, fit between the fulcrum tips  59  and the recesses  65  and  66  of the pivot body  26 .  
         [0038]     Returning to  FIG. 1 , it can be seen that the circuit breaker  10  includes a trigger  30  that is pivotably mounted to the housing at a pivot end  130 . The trigger can have the shape of a “horse hook” or a C-shaped bar, and is preferably stamped from a steel plate. Thus, the trigger can include a first leg  30   a  terminating in the pivot end  130 , a second leg  30   b  that is a generally obtuse angle relative to the first leg, and a third leg  30   c  that is itself at a generally obtuse angle relative to the second leg. The trigger  30  is oriented so that it can pivot within the channel  63  of the switch  25 , as well as within the trigger channel  61  defined by the floating breaker arm  22 .  
         [0039]     The trigger  30  includes a trigger pin  133  that extends perpendicularly through the trigger plate at the corner between the first and second legs  30   a,    30   b.  The third leg  30   c  terminates in a trigger tip  135  that engages a tripping lever  34 , as described herein. A spring aperture  131  is defined in the second leg  30   b,  generally closer to the third leg  30   c  than the first leg  30   a.  The spring aperture  131  provides a connection point for one end of a spring  31 , while the opposite end of the spring is connected to the floating breaker arm  22  at the spring slot  53 , as depicted in  FIG. 1 . The spring  31  is a compression spring meaning that its natural tendency is to draw the second leg  30   b  of the trigger  30  and the breaker arm  22  together. In the normal operating condition shown in  FIG. 1 , the spring  31  is in tension.  
         [0040]     The spring is held in tension and the mechanical breaker components maintained in their operative or “on” state shown in  FIG. 1  by interaction between the trigger tip  135  and the tripping lever  34 . Details of the tripping lever  34  can be found in  FIG. 5 . The lever includes a bushing  40  that receives a pivot pin  38  to pivotably mount the lever  34  within the housing  11 . The lever includes a latch plate  35  that defines an aperture  36  to receive the trigger tip  135  therein. Extending substantially perpendicularly from the latch plate is a trip plate  37  that can be actuated by a tripper pin  48 , shown in  FIG. 1 . The latch plate  35  includes a spring mount  68  projecting outward from the plate to support one end of a bias spring  39 . The other end of the bias spring  39  is disposed within a spring retainer  69  formed in the housing  11 . The bias spring  39  tends to push the latch plate  34  toward the trigger  30  to hold the trigger tip  135  within the latch aperture  36 . Preferably, the tripping lever  34  is stamped and bent into shape from a steel plate, but can also be molded from nylon or other high rigidity material.  
         [0041]     The circuit breaker  10  includes a magnetic lever and armature combination that senses a short circuit condition and operates to activate an indicator. In the illustrated embodiment, the breaker includes a magnetic lever  42  that is pivotably mounted to a magnetic armature  43 . Details of these two components are shown in  FIGS. 6 and 7 , respectively. The lever  42  includes a generally rectangular plate  70  that flares outward at one end into opposite pivot arms  71 . As shown in  FIG. 7 , the armature  43  is a metal plate bent generally into a U-shape, with one wall of the plate defining a pivot mount  75 . This mount  75  and a correspondingly configured mount in the housing  11  provide a pivot location for the two arms  71  of the lever  42 . A locator notch  76  an opposite wall of the armature plate can be used to fasten the armature  43  to the housing.  
         [0042]     As shown in  FIG. 6 , the magnetic lever  42  includes a tripping hook  72  projecting generally perpendicularly below the plate  70 . As illustrated in  FIG. 1 , this hook is disposed about the trip plate  37  of the tripping lever  34  and can be used to actuate the lever, as described herein. Also projecting generally perpendicularly from the plate  70 , but in an opposite orientation relative to the hook  72 , is a lever arm  73 . This lever arm is used to activate the fault indicator assembly  45  supported above the lever arm  73  within the housing  11 .  
         [0043]     Returning to  FIG. 7 , the armature  43  is again generally U-shaped, forming an elongated channel  77 . Spanning the channel and engaged to the opposite walls of the armature are two spaced pins  78  and  79  that are used to support and react a torsion spring, such as the spring  80  shown in  FIG. 8 . The coil of the spring  80  is mounted around the pin  78 , while a reaction leg  81  of the spring bears against the second pin  79 . The lever leg  82  of the spring  80  bears against the plate  70  of the magnetic lever  42  to bias the plate away from the armature  43 .  
         [0044]     The channel  77  and pins  78 ,  79  contain the conductor wire  19  extending through the armature  43 . Current flowing through the wire  19  creates a magnetic flux through the armature  43  which tends to attract the magnetic lever  42 . During a normal operating condition, this flux is not great enough to overcome the biasing force of the torsion spring  80 , so the lever  42  is normally separated from the armature  43  as shown in  FIG. 1 .  
         [0045]     However, when the lever  42  is attracted to the armature  43 , the upward movement of the lever bears against a fault indicator assembly  45 . Details of this assembly appear in  FIG. 10 . In particular, the assembly includes a housing  87  that supports a viewing window  88 . One end of the housing defines a slider opening  90 , while the opposite end of the housing is an open end  91  for insertion of the moving components of the indicator assembly. A pair of flanges  89  extend beneath the housing  87  to pivotably support an indicator carrier  103 . The bottom wall of the housing  87  defines an opening  92  to receive the locking tab  106  of the carrier  103 .  
         [0046]     The carrier  103  includes a bushing  105  through which a pin  101  extends to pivotably mount the carrier to the flanges  89 . The carrier includes a biasing arm  104  that includes an upwardly extending post  107  for receiving a biasing spring  109 . This biasing spring pushes the arm  104  away from the housing, which causes the carrier  103  to pivot about the pin  101  to push the locking tab  106  upward through the opening  92  in the housing  88 .  
         [0047]     When the locking tab  106  is in this normally biased position, the tab bears against an indicator slider  93 . The slider  93  is slidably disposed within the housing  88  and is biased toward one end of the housing by a pair of extension springs  100 . A cover  98  closes the open end  91  of the housing and provides a reaction surface for the springs  100 . Spring posts  99  can be provided to help support the extension spring  100 . The slider  93  includes a tongue  94  that extends through the opening  90 , as shown in  FIG. 10 , when a fault condition arises. However, in the normal operating position, the tongue  94  is substantially fully contained within the housing  88 , held in place by the locking tab  106 .  
         [0048]     The upper face of the slider  93  includes two differently colored sections, the first section  95  having a first indicator color and the second section  96  having a second indicator color. Either section is visible beneath the viewing window  88  depending upon the position of the slider. In a preferred embodiment, the first indicator color is black and nominally indicates a normal operating condition. The second color in section  96  can be red to indicate a fault condition.  
         [0049]     The exploded diagram  FIG. 11  depicts the elements of the magnetic tripper assembly  47 . This assembly is supported within the housing  11  below the tripping lever  34 , as shown in  FIG. 1 . The assembly  47  includes a housing  112  that supports an electromagnetic coil  114 . The coil  114  is connected to the current transformer  17  or the processor  16  to receive current as a function of the line current at line terminal  13 . Permanent magnets  115  are supported by holder  116  within the housing to complete the magnetic element of the assembly  47 . The core  117  extends through the coil  114  and is spring biased toward the cover  113  of the housing by way of a spring  119  acting against a flange  118 . A portion of the core  117  extends outside the cover  113  to engage a tripper pin  48 . The tripper pin  48  is situated directly beneath the trip plate  37  of the tripping lever  34 , as shown in  FIG. 1 . In the normal operating condition, the coil  114  maintains the core  117  retracted within the housing  112  so that the tripper pin  48  does not bear against the lever  34 .  
         [0050]     The current rating or ground fault current specification for the circuit breaker  10  can be determined by way of a replaceable chip assembly  50 , such as illustrated in  FIG. 12 . The assembly  50  can include a housing  122  with a removable cover  123  to provide access to a resistor or resistors  125  mounted therein. Contact pins  126  are electrically connected to the resistor(s)  125  and provide means for making electrical contact with a mounting pad of the processor  16 . The replaceable chip assembly thus is integrated into the shaping and amplification circuitry of the processor to determine the tripping current conditions. The chips  50  can provide current rating from as low as 0.1 amps to as high as 125 amps and beyond by proper selection of the resistor(s) within the chip. Thus, a single circuit breaker  10  can be modified for virtually any electrical system application by the simple expedient of changing out the chip assembly  50 .  
         [0051]     With the details of the breaker components described, attention can now turn to the function of these components. As indicated above,  FIG. 1  depicts the breaker  10  in its normal operating condition—i.e., during normal current flow through the breaker. In this configuration, the two contacts  21  and  23  are in engagement. The position of the floating breaker arm  22  is maintained as shown in the detail view of  FIG. 16 . In this normal operating configuration, the trigger tip  135  of the trigger  30  is held in place by the tripping lever  34 , with the tip  135  disposed within the aperture  36 . The trigger  30  thus fixes the orientation of the spring  31  which tends to pull the floating breaker arm  22  upward toward the switch  25 . More specifically, the spring  31  tends to force the fulcrum tip  59  of each side wall  55  of the breaker arm  22  into the cam recess  65  of the pivot body  26  of the switch  25 .  
         [0052]     The trigger contact  56  of the arm  22  bears against the fulcrum bar  137  of the trigger  30  to form a mechanical linkage between the floating breaker arm  22 , spring  31  and cam recess  65 . The line of action of the spring  31  is this orientation keeps the breaker arm in the orientation show in  FIG. 1  so that the electrical contacts remain in contact. The force of the fulcrum tip  59  of the breaker arm  22  upward against the cam recess  65  tends to pivot the switch  25  about its pivot mount  27  so that the switch handle is oriented to the left, as shown in  FIG. 1 . The switch is in its “on” position when oriented to the left as shown in the figure.  
         [0053]     Referring now to  FIGS. 13 and 17 , the circuit breaker is depicted in the configuration arising when the breaker switch  25  is deliberated turned to its “off” position. In this position, the switch handle is oriented to the right, as shown in  FIG. 13 . Again, appropriate markings can provide an additional visual indication that the circuit breaker  10  has been shut off. As the breaker switch  25  is rotated about its pivot mount  27 , the fulcrum tip  59  and bearing edge  55   a  of the floating breaker arm  22  bear against the cam recess  65  and pivot recess  66  of the switch  25 . The trigger  30  is still maintained in its poised orientation, since no fault condition has occurred to trip the trigger. Thus, the trigger  30  provides a stationary anchor for the spring  31 , while the fulcrum bar  137  of the trigger provides a stationary fulcrum point for movement of the breaker arm  22 . As the switch rotates, the breaker arm  22  tends to pivot relative to the switch as the spring  31  tries to pull the breaker arm upward against the fulcrum bar  137 . When the switch  25  is moved to its far right extent, the bearing edge  55   a  of the floating breaker arm  22  is pushed against the pivot recess of the switch. Again, the linkage cooperation between the fulcrum bar  137  and spring  31  hold the breaker arm  22  in the position shown in  FIG. 13 .  
         [0054]     When the switch movement is reversed—i.e., when the switch is turned back to its “on” position shown in  FIG. 1 —the cam recess  65  pushes the fulcrum tip  59  of the breaker arm  22  to the right. The linkage formed by the fulcrum bar  137  and spring  31  will cause the breaker arm  22  to snap to its “on” position of  FIG. 1  once the line of action between the cam recess  65  and fulcrum tip  59  moves to the right of the line of action of the spring  31 .  
         [0055]     When a short circuit condition arises, the circuit breaker  10  moves to the configuration shown in  FIGS. 14 and 18 . In a short circuit condition, current flowing through the conductor wire  19  exceeds a predetermined limit. In this condition, the armature  43  produces a magnetic flux that is sufficient to overcome the biasing force of the torsion spring  80  to attract the magnetic lever  42 . The lever  42  pivots upward so that the plate  70  contacts the armature  43 .  
         [0056]     When the lever  42  pivots upward, the tripping hook  72  also moves upward until it contacts trip plate  37  of tripping lever  34 . This upward movement causes the tripping lever  34  to rotate so that the latch plate  35  moves clear of the tip  135  of the trigger. More specifically, rotation of the tripping lever  34  releases the tip  135  from the aperture  36  in the latch plate.  
         [0057]     With the tip  135  free to move, the spring  31  draws the trigger  30  and floating breaker arm  22  together. As the trigger  30  rotates about its pivot  130 , the fulcrum bar  137  no longer restrains the movement of the breaker arm  22 . Instead, the cam recess  65  and pivot recess  66  of the breaker switch  25  controls the upward movement and rotation of the arm  22 . The breaker arm  22  is thus held in the position shown in  FIG. 14  by abutment of its side walls  55  against the housing and by pressure of the fulcrum tip  59  against the switch pivot body  26 . This pressure from the fulcrum tip also causes the switch to pivot slightly about its pivot mount  27  so that the switch moves to a neutral position, as shown in  FIG. 14 .  
         [0058]     This rotation of the switch is also facilitated by pressure from the trigger pin  133  against the cam edge  64  of the pivot body  26 . As the spring  31  tries to contract, it causes the trigger  30  to rotate until the pin  133  bears against the cam edge  64 . This same contact is also used to reset the circuit breaker. In particular, when the fault condition has been resolved, the breaker can be reset by first rotating the switch to the right. This rotation of the switch causes the cam edge  64  to push against the trigger pin  133 , thereby causing the trigger  30  to pivot about its pivot point  130 . As the trigger continues to pivot, the trigger tip  135  bears against the latch plate  35  of the tripping lever, causing the lever to rotate about its own axis. Eventually, the trigger  30  has pivoted enough so that the tip  135  becomes lodged in the aperture  36 , thereby resetting the trigger  30 . The switch can then be rotated back to the left, to its “on” position, to force the floating breaker arm  22  into electrical contact with the stationary contact  21 .  
         [0059]     Referring back to  FIG. 14 , when the short circuit condition arises, it is certainly desirable to provide a visual indication of the condition to eliminate the risk of injury to the unwary. When the magnetic lever  42  pivots upward under the influence of the armature  43 , as described above, the lever arm  73  also moves upward into contact with the indicator carrier  103 , and more particularly against the bias arm  104 . As explained above in connection with  FIG. 10 , this movement causes the carrier  103  to pivot, which causes the locking tab  106  to retract from the opening  92  in the indicator assembly housing  87 . When the tab  106  has moved a sufficient distance, it disengages the slider  93  so that the spring  100  push the slider to the left in  FIG. 14 . With this movement, the tongue  94  extends out slider opening  90  so that the tongue contacts the breaker switch  25 , as shown in  FIG. 14 . At the same time, this translation of the slider  93  moves the second color section  96  into position beneath the viewing window  88 . Again, the second section  96  has a red color to provide an immediate and urgent indication of the fault condition. Thus, the circuit breaker  10  provides an indication of a short circuit condition by the red color of the indicator assembly  45  as well as the neutral position of the switch  25 .  
         [0060]     When the breaker is reset, the switch is first rotated to the right, as described above for resetting the trigger. This same movement also resets the fault indicator assembly  45 . As the trigger is pivoted to the right, it pushes against the tongue  94 , causing the slider  93  to retract within the housing  87 . When the slider  93  has moved sufficiently far, the locking tab  106  can pivot upward under inducement from the biasing spring  109  until it locks the slider in the position shown in  FIG. 1 . It should be noted that while the fault condition exists, the magnetic lever  42  will remain in its upward position. When the lever is in this position, the lever arm  73  will continue to bear against bias arm  104  of the indicator carrier  103 , which will prevent rotation of the carrier back to its original position. However, once the fault condition has been rectified, the torsion spring  80  will push the magnetic lever  42  back to its original position, thereby freeing the indicator carrier  103 .  
         [0061]     An over-current fault is illustrated in  FIG. 15 . As explained above, the magnet tripper  47  is supplied with current from either the current transformer  17 , or from the processor  16 . Most preferably, the current is obtained from the processor through a relay. When the processor determines that an over-current condition exists (by evaluating the signal form the current transformer), it opens the relay which terminates current to the coil  114  of the magnet tripper  47 . When the coil is inactive, the magnets  115  are released, which allows the core  117  to travel upward under influence from the spring  119 . This upward movement is carried through by the tripper pin  48  until the pin contacts and rotates the trip plate  37  of the tripper lever  34 . At this point, the movement of the lever  34  and the remaining mechanical components of the breaker continue as described above with respect to  FIGS. 14 and 18 .  
         [0062]     The present invention also contemplates a ground fault breaker and indicator system. Referring to  FIG. 19 , an alternative circuit breaker  150  is shown. This breaker can be substantially similar to the breaker  10  described above, with the addition of a ground fault indicator  159  and a zero current transformer (ZCT)  154 . In fact, these components can be added to the breaker  10 . With this ground fault responsive system, the processor  152  receives current signals from the current transformer  153  and the ZCT  154 .  
         [0063]     The ground fault indicator  159  can be constructed similar to the magnetic tripper  47 . The top portion of the core  117  can be modified to carry certain indicia to signify a ground fault condition. The coil  114  of the magnet tripper and the comparable coil of the ground fault indicator can both be connected to the ZCT  154 . When a ground fault condition arises, current through the ZCT ceases, thereby deactivating the two coils. When the magnetic tripper  47  coil is deactivated, the tripper pin  48  operates as explained above with respect to  FIG. 15 . In addition, when the coil of the ground fault indicator  159  is deactivated, the core  117  pops up, exposing the top portion of the core. In a preferred embodiment, the top portion of the core can be yellow in color or carry a yellow cap. When current is restored, the respective coils are re-energized and both the tripper pin  48  and yellow indicator are retracted to signify that the fault condition has been cleared. The circuit breaker  150  can be provided with a test switch  160  that allows personnel to temporarily interrupt current to the ground fault indicator  159  to verify its operability without tripping the mechanical components of the breaker and thereby disconnecting the load.  
         [0064]     While the invention has been illustrated and described in detail in the drawings and foregoing description, the same should be considered as illustrative and not restrictive in character. It is understood that only the preferred embodiments have been presented and that all changes, modifications and further applications that come within the spirit of the invention are desired to be protected.