Circuit breaker with a dual test button mechanism

Information

  • Patent Grant
  • 6259340
  • Patent Number
    6,259,340
  • Date Filed
    Monday, May 10, 1999
    25 years ago
  • Date Issued
    Tuesday, July 10, 2001
    23 years ago
Abstract
In an exemplary embodiment of the invention, a dual test mechanism is presented for use in a circuit breaker. More specifically, the dual test mechanism includes a dual test button which comprises a single switch for testing both the AFCI and GFCI circuits of the breaker. The test mechanism includes a circuit board, which forms a part of the circuit breaker, and a test button assembly which includes a test button and signaling components which are electrically connected to the circuit board.
Description




BACKGROUND OF THE INVENTION




The present invention relates generally to a circuit breaker. More specifically the present invention relates to a dual test button and test mechanism to check both an arc fault circuit interruption (AFCI) and a ground fault circuit interruption (GFCI) in a circuit breaker.




Conventional residential and light industrial and commercial circuit breakers typically have a thermal trip mechanism which responds to persistent overcurrents of moderate magnitude to provide a delayed trip in the breaker. Also included in the circuit breaker is a magnetic trip mechanism which responds instantaneously to overcurrent conditions of greater magnitudes. It is becoming more common for these circuit breakers to further include a ground fault trip mechanism as one of the active mechanisms. The ground fault trip mechanism includes a trip unit which detects faults between the line conductor and ground and the neutral conductor and ground. Line to ground faults are commonly detected by the use of a differential transformer. The line and neutral conductors are passed through the coil so that in the absence of a line to ground fault, the currents are equal and opposite and no signal is generated. However, when a line to ground fault exists, it creates a sizeable imbalance between the two currents in the two conductors which can be level detected As is known, a neutral to ground fault may be detected by injecting a signal onto the neutral conductor which will produce an oscillation if feedback is provided.




In addition, conventional circuit breakers include mechanisms designed to protect against arc faults. For example, an arc fault may occur in the device when bare or stripped conductors come into contact with one another and the current caused by such a fault produces magnetic repulsion forces which push the conductors apart, thereby striking an arc. The arc that is caused by these faults can damage the conductors by melting the copper therein and this is especially true for stranded wire conductors such as extension cords, which can ignite surrounding materials.




Typically, the circuit breaker includes contacts that open upon sensing arcing from line to ground and/or from line to neutral. Arc fault circuit breakers typically use a differential transformer to measure arcing from line to ground. Detecting arcing from line to neutral is accomplished by detecting rapid changes in load current by measuring voltage drop across is a relatively constant resistance, usually a bi-metal resistor.




Unfortunately, many conventional circuit breakers, including residential circuit breakers, do not permit the user to test both the AFCI and GFCI circuits in the device. Furthermore, the ability to test both of these circuits is very important for customer safety and because a vast amount of individuals do not understand the implications of a circuit failure, it is important to best educate these individuals about these implications and what systems are available to minimize the likelihood that such a circuit failure occurs.




BRIEF SUMMARY OF THE INVENTION




In an exemplary embodiment of the invention, a dual test mechanism is presented for use in a circuit breaker. More specifically, the dual test mechanism includes a dual test button which comprises a single switch for testing both the AFCI and GFCI circuits of the breaker. The test mechanism includes a circuit board, which forms a part of the circuit breaker, and a test button assembly which includes a test button and signaling components which are electrically connected to the circuit board.




The test button has a first position and a second position, wherein positioning the test button in the first position produces a first signal and positioning the test button in the second position produces a second signal. A trip mechanism is included in the circuit breaker and includes a pair of separable contacts, wherein the trip mechanism is electrically connected to the circuit board so that in response to receiving one of the first and second signals, the circuit board generates a trip signal which directs the trip mechanism to separate the pair of separable contacts. In the preferred embodiment, the first position comprises a test position for the AFCI circuit and the second position comprises a test position for the GFCI circuit. Thus, the present invention permits the customer to test both the AFCI and GFCI circuits by positioning a single test button accordingly in either the first or second test button positions.




The above-discussed and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description and drawings.











BRIEF DESCRIPTION OF THE DRAWINGS




Referring now to the drawings wherein like elements are numbered alike in the several Figures:





FIG. 1

is a perspective view of a dual test button for use in a dual test mechanism in accordance with the present invention;





FIG. 2

is a side elevation view of an exemplary printed circuit board layout in accordance with the present invention;





FIG. 3

is a bottom plan view of the printed circuit board of

FIG. 2

taken along the line


3





3


,





FIG. 4

is a perspective view of a single pole circuit breaker in accordance with present invention;





FIG. 5

is an exploded view of the mechanical compartment of the single pole circuit breaker of

FIG. 4

;





FIG. 6

is an exploded view of the electronics compartment of the single pole circuit breaker of

FIG. 4

;





FIG. 7

is a side elevation view of a dual test mechanism including the dual test button of

FIG. 1

for use in a circuit breaker in accordance with the present invention; and





FIG. 8

is a schematic of an exemplary circuit for the dual test button of the present invention.











DETAILED DESCRIPTION OF THE INVENTION




Referring to

FIG. 1

, an exemplary dual test button for use to check both AFCI and GFCI circuits in a circuit breaker


100


(

FIG. 4

) is generally shown at


10


. Test button


10


includes a first cantilevered surface


12


and a second cantilevered surface


14


which are designed as surfaces for the user to depress depending upon which circuit is to be tested in circuit breaker


100


. More specifically, first cantilevered surface


12


is depressed if testing of the AFCI circuit is desired and second cantilevered surface


14


is depressed if testing of the GFCI circuit is desired. First and second cantilevered surfaces


12


and


14


are integral with one another and converge along a central line. A perimetric lip


16


extends around first and second cantilevered surfaces


12


and


14


so that surfaces


12


and


14


extend above perimetric lip


16


. A bottom portion of test button


10


comprises a clamp member


18


which receives a pivotable leaf spring


20


which forms a part of a test button assembly


32


(shown in FIG.


2


). Clamp member


18


has a pair of biasing arms


22


which securely hold pivotable leaf spring


20


therebetween. Pivotable leaf spring


20


pivots when either first or second cantilevered surfaces


12


and


14


are depressed. Preferably, test button


10


is formed of a plastic material as is known in the art.




Turning now to

FIGS. 1-3

which illustrate exemplary current sensing components


30


for use in circuit breaker


100


(

FIG. 4

) along with test button assembly


32


. Current sensing components


30


comprise a circuit board


34


which is electrically connected to a solenoid


36


and a current sensing transformer


38


. Furthermore, test button assembly


32


includes signaling components comprising a pivotable leaf spring


20


which is disposed intermediate a first flat conductor (flat)


40


and a second flat conductor (flat)


42


, all of which are electrically connected to circuit board


34


. Pivotable leaf spring


20


is preferably a planar member, while first and second flats


40


and


42


each have a lower planar segment and an angled upper segment which is inclined toward pivotable leaf spring


20


. It being understood that test button


10


is secured to pivotable leaf spring


20


by simply inserting a top end of pivotable leaf spring


20


within clamp member


18


. The biasing forces of the pair of arms


22


pinch and hold pivotable leaf spring


20


in place.




Test button assembly


32


comprises a two position switch assembly (AFCI and GFCI), wherein depressing first cantilevered surface


12


causes pivotable leaf spring


20


to contact second flat


42


resulting in a first signal being injected into circuit board


34


, wherein the first signal comprises a test signal for the AFCI circuit. In contrast, depressing second cantilevered surface


14


causes pivotable leaf spring


20


to contact first flat


40


resulting in a second signal being injected into circuit board


34


, wherein the second signal comprises a test signal for the GFCI circuit. Upon receiving either the first or the second signal, circuit board


34


generates a trip signal to solenoid


36


resulting in the actuation of solenoid


36


which causes a pair of separable contacts to separate and interrupt the current flow in circuit breaker


100


(FIG.


4


). The precise testing mechanisms and signaling will be described in great detail hereinafter.




Solenoid


36


includes a plunger assembly


44


at one end, wherein plunger assembly


44


includes a rod having an end extension


46


which attaches at a right angle to the plunger rod. End extension


46


comprises the component of plunger assembly


44


which moves within a recess


48


formed in circuit board


34


. Referring to

FIG. 2

, the actuation of solenoid


36


causes plunger assembly


44


to move in a left-to-right direction and end extension


46


moves within recess


48


in a direction away from circuit board


34


. End extension


46


is intended to engage a test mechanism


200


(shown in

FIG. 7

) which causes the pair of contacts to separate and interrupt current flow within circuit breaker


100


, as will be described hereinafter.




Circuit board


34


, test button assembly


32


and solenoid


36


and test mechanism


200


(

FIG. 7

) may be used as a component of any number of suitable circuit breakers in which the selected movement of dual test button


10


permits one of two test signals to be injected into circuit board


34


resulting in the testing of both AFCI and GFCI circuits within circuit breaker


100


. For the purpose of illustration only and not limitation, an exemplary single pole arc circuit board


100


is illustrated in

FIGS. 4-6

and is further described in commonly assigned U.S. patent application Ser. No. 09/246,322 filed on Feb. 9, 1999, which is hereby incorporated by reference in its entirety.




Referring to

FIG. 4

, circuit breaker


100


comprises a first housing


102


, a second housing


104


, and a cover


106


that are assembled securely together with a plurality of bolts (not shown). First housing


102


defines a mechanical compartment


108


, having load current carrying and switching components


110


disposed therein (see FIG.


5


). Second housing


104


defines an electronics compartment


112


, having current sensing components


114


and neutral current carrying components


116


disposed therein (see FIG.


6


). A load current from a source (not shown) connects to a line connection


118


(see FIG.


5


), and conducts along the current carrying and switching components


110


to a load lug


120


for customer connection to a load (not shown). A neutral current from the load connects to a neutral lug


122


, (see

FIG. 4

) and conducts along the neutral current carrying components


116


to a neutral return wire


124


for customer connection to the source. Arc faults are sensed and processed by sensing components


114


. As more particularly described hereinafter, arc fault circuit breaker


100


is preferably assembled such that electrical interconnections, i.e., electrical connections between the mechanical and electronics compartments


108


and


112


, are made without disassembling any previously assembled compartment.




Referring to

FIG. 5

, the mechanical compartment


108


is shown in detail. First housing


102


is generally rectangular in shape, and formed of electrical insulative material, i.e., plastic. First housing


102


comprises a first insulative tab


126


, a first rim


128


, and a first side wall


130


. First tab


126


protrudes forwardly from the front of first housing


102


adjacent load lug


120


to provide an insulative barrier. First rim


128


extends around the periphery of first side wall


130


. A first rectangular slot


132


is located in first rim


128


at the top and back of first housing


102


and is sized to receive a pole handle


134


. First side wall


130


and first rim


128


define mechanical compartment


108


which includes the load current carrying and switching components


110


. The load current carrying and switching components


110


within the mechanical compartment


108


are electrically connected, e.g., welded, bolted, or crimped, to form a load current path. The load current path begins at line connection


118


where the load current enters the mechanical compartment


108


. Line connection


118


includes a lower tab


138


to connect to a source line (not shown), and a fixed contact


140


which extends downwardly from the upper end of line connection


118


. A blade


142


is pivotally engaged to first housing


102


and is pivotally attached to insulated pole handle


134


. A lower end of blade


142


includes a flat contact


144


which is forcibly biased against contact


140


to provide electrical continuity for the load current. Pole handle


134


is pivotally attached to first housing


102


and extends outwardly from mechanical compartment


108


into electronics compartment


112


.




Blade


142


is electrically connected to a bottom distal end of a bimetal resistor


146


via a braid


148


. A top distal end of bimetal resistor


146


is in turn electrically connected to an L-shaped strap


150


. L-shaped strap


150


comprises a vertical strap body


152


and a horizontal strap extension


154


. Horizontal strap extension


154


forms a substantially right angle with vertical strap body


152


, and extends outwardly from mechanical compartment


108


into electronics compartment


112


. A load terminal


156


also extends outwardly from the mechanical compartment


108


into electronics compartment


112


. Load terminal


156


is in turn electrically connected to load lug


120


. The load current path conducts the load current from the line connection


118


, through contacts


140


and


144


, through blade


142


, braid


148


, bimetal resistor


146


, and L-shaped strap


150


. At this point, the load current path passes out of the mechanical compartment


108


through horizontal strap extension


154


. The load current path returns to the mechanical compartment


108


through load terminal


156


and out through the load lug


120


to the load. When an arc fault is detected the pole handle


134


pivots clockwise, which in turn pivots blade


142


to separate contacts


140


and


144


and thereby open the load current path.




A twisted pair conductor


158


is electrically connected to the bottom distal end of bimetal resistor


146


and horizontal strap extension


154


of the L-shaped strap


150


to sense arcing from the line to neutral as is well known. This is accomplished by measuring the voltage drop across the bimetal resistor


146


that results from rapid changes in load current caused by arcing from line to neutral.




Referring to

FIG. 6

, the electronics compartment


112


is shown in detail. Second housing


104


is generally rectangular in shape and formed of electrical insulative material, i.e., plastic. Second housing


104


comprises a second insulative tab


160


, a second rim


162


, and a second side wall


164


. Second tab


160


protrudes forwardly from the front of second housing


104


adjacent neutral lug


122


to provide an insulative barrier. Second rim


162


extends around the periphery of second side wall


164


. A second rectangular slot


166


is located in rim


162


and cooperates with slot


132


to receive and secure pole handle


134


when housings


102


and


104


are assembled together. Second side wall


164


and second rim


162


define the electronics compartment


112


which includes the current sensing components


114


and the neutral current carrying components


116


. The second housing


104


is assembled securely against first housing


102


with a plurality of bolts (not shown) to enclose mechanical compartment


108


and to capture the components wiin, as well as to insulate and secure load lug


120


between tabs


126


and


160


.




Second side wall


164


of second housing


104


includes rectangular through holes


168


and


170


and circular through hole


172


to provide openings in the second housing


104


to permit the load terminal


156


, horizontal strap extension


154


and twisted pair conductor


158


to extend through to the electronics compartment


112


. This enables all electrical interconnections between compartments


108


and


112


to be completed in electronics compartment


112


. During production, this allows compartments


108


and


112


to be assembled sequentially without the need to disassemble mechanical compartment


108


. That is, mechanical compartment


108


is assembled first with the interconnecting components


154


,


156


and


158


extending outwardly from the compartment


108


. Second housing


104


is then assembled to first housing


102


enclosing the mechanical compartment


108


, but allowing the interconnecting components


154


,


156


, and


158


to extend therethrough. The electronics compartment


112


may then be assembled and the associated components be interconnected to the components of the mechanical compartment


108


without any disassembly of mechanical compartment


112


. This provides for a large work space for tooling and assembly when interconnecting the components of the compartments


108


and


112


. Therefore, high quality interconnections are more consistently, and cost effectively made then in prior art circuit breakers.




Second side wall


164


further includes a window


190


, preferably in the shape of a rectangle. Window


190


is intended to receive end extension


46


of plunger


44


of solenoid


36


. More specifically, end extension


46


freely moves within window


190


upon actuation of solenoid


36


after circuit board


34


generates a trip signal which is received by solenoid


36


. End extension


46


engages test mechanism


200


(shown in

FIG. 7

) to cause handle


134


to pivot resulting in contacts


140


and


144


separating.




Current sensing components


114


comprise circuit board


34


which is electrically connected to solenoid


36


, current sensing transformer


38


and optional to current sensing transformer


38


′. Upon receiving signals indicative of an arc fault, circuit board


34


provides a trip signal to trip the arc fault circuit breaker


100


.




Twisted pair conductor


158


is electrically interconnected to circuit board


34


. Circuit board


34


senses the voltage across the bi-metal resistor


146


and generates a trip signal to actuate solenoid


36


in response to a rapid voltage drop indicative of arcing across the line and neutral leads.




The load current path is completed by electrically interconnecting strap extension


154


and load terminal


156


to a respective distal ends of a wire connector


180


. Wire connector


180


can be formed from various suitable conductive materials, e.g., insulated wire, rectangular formed magnetic wire, square formed magnetic wire, or insulated sleeve covered braided copper. Wire connector


180


is routed through a center of sensing transformer


38


such that the flow of the load current through the center of transformer


38


is in a known direction.




The neutral current carrying components


116


within the electronics compartment


112


are electrically connected, e.g., welded, bolted, or crimped, to form a neutral current path for the neutral current. The neutral current path begins at neutral lug


122


where the neutral current enters the electronics compartment


112


. Neutral lug


122


secures the neutral lead connected to the load against a neutral terminal


182


to provide electrical continuity thereto. Neutral terminal


182


is electrically connected to neutral return wire


124


via a copper braid


184


. An insulated sleeve


186


surrounds a portion of copper braid


184


and provides electrical insulation between copper braid


184


and circuit board


34


. Copper braid


184


is routed through the center of sensing transformer


38


such that the flow of the neutral current through the center of transformer


38


is in the opposite direction of the flow of the load current through wire connector


180


.




Both the copper braid


184


of the neutral current path, and wire connector


180


of the load current path are routed through the current sensing transformer


38


to sense arcing from line to ground as is well known. This is accomplished by routing the flow of the neutral current through the sensing transformer


38


in the opposite direction to the flow of the load current. The total current flow through sensing transformer


38


thus cancels unless an external ground fault current is caused by arcing from line to ground. The resulting differential signal, sensed by sensing transformer


38


, is indicative of the ground fault current and is processed by circuit board


34


.




Optional current sensing transformer


38


′ is used for ground fault applications where a separate sensor is needed to detect improper wiring by the customer, e.g., the neutral current path is wired backwards. That is, copper braid


184


of the neutral current path is routed through the optional current sensing transformer


38


′. The resulting signal, sensed by optional current sensing transformer


38


′, is indicative of the neutral current direction and magnitude, and is processed by circuit board


34


.




Turning now to

FIGS. 1-8

.

FIG. 7

illustrates test mechanism


200


in greater detail. It being understood that test mechanism


200


of

FIG. 7

is merely exemplary in nature and it is within the scope of the present invention that other known test mechanism


200


may be employed with test button assembly


32


including dual test button


10


and circuit board


34


to cause handle


134


to pivot resulting in contacts


140


and


144


opening to interrupt current during either AFCI or GFCI tnp conditions. Test mechanism


200


includes a latch assembly


202


having a pivotable armature latch (not shown). The pivotable armature latch comprises the main component of test mechanism


200


which interacts with end extension


46


in that upon actuation of solenoid


36


, the solenoid rod is driven causing end extension


46


to ride within window


190


(FIG.


6


). As end extension


46


is driven itself, it contacts the annature latch causing the armature latch to rotate counterclockwise.




The pivotable armature latch selectively engages and positions a cradle


204


so that when the armature latch is rotated counter clockwise, cradle


204


is released from the armature latch resulting in cradle


204


being free to rotate. Cradle


204


rotates downward in a clockwise manner and falls out of window


190


. A spring


206


interconnected between blade


142


and cradle


204


creates a biasing force therebetween so that when cradle


204


rotates clockwise, after being released from the annature latch, the spring biasing forces causes blade


142


and handle


134


to rotate to a trip position, wherein contacts


140


and


144


are opened.




As best shown in

FIGS. 2 and 6

, a test wire


195


is routed through sensing transformer


38


, such that the flow of current in test wire


195


through the center of sensing transformer


38


is in a known direction. During non-test and non-trip conditions, the total current flowing in opposite directions through transformer


38


cancels one another and thus sensing transfonner


38


does not detect a differential signal, which is indicative of a trip or test condition. Test wire


195


is electrically connected to circuit board


34


and test button assembly


32


so that when the second signal (GFCI test signal) is generated when pivotable leaf spring


20


and first flat


40


make contact, a current is passed through test wire


195


causing a current differential through sensing transformer


38


. More specifically, one end of test wire


195


is electrically connected to first flat


40


and an opposite end of test wire


195


is electrically connected to horizontal strap extension


154


after test wire


195


has passed through sensing transformer


38


.




Referring to

FIGS. 1-7

, in exemplary circuit breaker


100


, the testing of the AFCI circuit proceeds in the following manner. First cantilevered surface


12


of test button


10


is depressed causing pivotable leaf spring


20


to contact second flat


42


resulting in the first signal being injected into circuit board


34


. The first signal comprises a test signal for the AFCI circuit of circuit breaker


100


and in response to the first signal, circuit board


34


generates a trip signal which is communicated with solenoid


36


. Upon receipt of the trip signal, solenoid


36


is actuated and plunger


44


is driven so that end extension


46


of plunger


44


contacts and causes the armature latch to rotate counter clockwise, thereby releasing cradle


204


. This results in handle


134


being rotated causing contacts


140


and


144


to open. Test button


10


is designed so that once first cantilevered portion


12


is no longer depressed, test button


10


moves back to its original off position, wherein pivotable leaf spring


20


is centered and not in contact with either first or second flats


40


and


42


. Consequently, after the trip mechanism of circuit breaker


100


, including handle


134


, blade


142


and contacts


140


and


144


are reset to a non-trip position, test button


10


is in an off position and thus no test signals are being delivered to circuit board


34


.




In order to test the GFCI circuit of circuit breaker


100


, second cantilevered surface


14


is depressed causing pivotable leaf spring


20


to contact first flat


40


resulting in the second signal being injected into circuit board


34


in the following manner. Upon contact between pivotable leaf spring


20


and first flat


40


, test wire


195


, which is routed through sensing transformer


38


, carries current through sensing transformer


38


thereby canceling the indifference in total current flowing through sensing transformer


38


because the opposing flow of current through sensing transformer


38


no longer cancels one another. The resulting differential signal, sensed by sensing transformer


38


, is indicative of the ground fault current and is processed by circuit board


34


. As previously described, in response to the second signal, circuit board


34


generates a trip signal which is communicated with solenoid


36


. Upon receipt of the trip signal, solenoid


36


is actuated and engages test mechanism


200


to cause rotation of handle


134


and opening of contacts


140


and


144


in the manner described hereinbefore.

FIG. 8

is a schematic of exemplary circuitry for dual test button


10


and is therefore self-explanatory in nature. Thus, the present invention provides a means for providing a first test signal and a second test signal, wherein the first test signal is generated to test the AFCI circuit and the second signal is generated to test the GFCI circuit. Test button assembly


32


is merely one exemplary means for providing these two signals and it is within the scope of the present invention that other means may be used such as a switching device, e.g., toggle switch having two positions which generate first and second test signals.




Of course one of sill in the art would appreciate that the test mechanism


200


and dual test button


10


may be employed in a two pole arc fault circuit breaker. In this embodiment, the AFCI and GFCI of the two pole arc fault circuit breaker are easily and conveniently tested




While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is understood that the present invention has been described by way of illustrations and not limitation.



Claims
  • 1. A test mechanism for a circuit breaker comprising:a circuit board; a test button assembly including a test button, the test button including a top portion having first and second cantilevered surfaces, and a bottom portion having a clamp member, the clamp member having a pair of biasing arms pinching a first end of a pivotable conductor to the test button, the pivotable conductor comprising a leaf spring and further comprising a second end, the test button assembly further including signaling components comprising first and second flat conductors which are electrically connected to the circuit board, wherein depressing the first cantilevered surface places the test button in a first position and moves the second end of the pivotable conductor into contact with the second flat conductor to direct a first test signal to the circuit board, and depressing the second cantilevered surface places the test button in a second position and moves the second end of the pivotable conductor into contact with the first flat conductor to direct a second test signal to the circuit board; and a trip mechanism including a pair of separable contacts, the trip mechanism being electrically connected to the circuit board so that in response to receiving one of the first and second test signals, the circuit board generates a trip signal causing the trip mechanism to separate the pair of separable contacts.
  • 2. The test mechanism of claim 1 wherein the circuit breaker includes an arc fault circuit interruption circuit (AFCI) and a ground fault circuit interruption (GFCI) circuit.
  • 3. The test mechanism of claim 2 wherein the first position comprises a test position for the AFCI circuit and the second position comprises a test position for the GFCI circuit.
  • 4. The test mechanism of claim 1 wherein the circuit breaker further includes a current sensing transformer.
  • 5. The test mechanism of claim 4 wherein the first flat conductor is electrically connected to one end of a test wire which passes through the current sensing transformer, an opposite end of the test wire being electrically connected to a bi-metal resistor.
  • 6. The test mechanism of claim 5 wherein the second signal is provided by passing current through the test wire when the pivotable conductor and the first conductive flat are in contact.
  • 7. The test mechanism of claim 1 wherein the trip mechanism includes a pivotable handle.
  • 8. The test mechanism of claim 7 wherein the trip mechanism includes a solenoid which is electrically connected to the circuit board and actuation of the solenoid causes the handle to pivot and separate the contacts.
  • 9. The test mechanism of claim 8 wherein the solenoid is actuated by receipt of the trip signal from the circuit board.
  • 10. A circuit breaker comprising:a trip unit including a circuit board; a pair of separable contacts for interrupting the flow of current; and a test mechanism including a test button, the test button including a top portion having first and second cantilevered surfaces, and a bottom portion having a clamp member, the clamp member having a pair of biasing arms pinching a first end of a pivotable conductor to the test button, the pivotable conductor comprising a leaf spring and further comprising a second end, the test button assembly further including signaling components comprising first and second flat conductors, wherein depressing the first cantilevered surface places the test button in a first position and moves the second end of the pivotable conductor into contact with the second flat conductor to direct a first test signal to the circuit board, and depressing the second cantilevered surface places the test button in the second position and moves the second end of the pivotable conductor into contact with the first flat conductor to direct a second test signal to the circuit board, and wherein the circuit board generates a trip signal in response to receiving one of the first and second test signals, the trip signal being delivered to an actuator which causes separation of the contacts.
  • 11. The circuit breaker of claim 10 wherein the first position is for testing an arc fault circuit interruption and the second position is for testing a ground fault circuit interruption.
  • 12. The circuit breaker of claim 10 wherein the actuator comprises a solenoid.
  • 13. The circuit breaker of claim 10, further including an arc fault circuit interruption circuit (AFCI) and a ground fault circuit interruption (GFCI) circuit.
  • 14. The circuit breaker of claim 13 wherein the first position comprises a test position for the AFCI circuit and the second position comprises a test position for the GFCI circuit.
  • 15. The circuit breaker of claim 10 wherein the first flat conductor is electrically connected to one end of a test wire which passes through the current sensing transformer, an opposite end of the test wire being electrically connected to a bi-metal resistor.
  • 16. The circuit breaker of claim 15 wherein the second signal is provided by passing current through the test wire when the pivotable conductor and the first conductor flat are in contact.
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